Author name code: jordan-stuart
ADS astronomy entries on 2022-09-14
author:"Jordan, Stuart D."
------------------------------------------------------------------------
Title: Gaia Data Release 3: Summary of the content and survey
properties
Authors: Gaia Collaboration; Vallenari, A.; Brown, A. G. A.; Prusti,
T.; de Bruijne, J. H. J.; Arenou, F.; Babusiaux, C.; Biermann, M.;
Creevey, O. L.; Ducourant, C.; Evans, D. W.; Eyer, L.; Guerra, R.;
Hutton, A.; Jordi, C.; Klioner, S. A.; Lammers, U. L.; Lindegren,
L.; Luri, X.; Mignard, F.; Panem, C.; Pourbaix, D.; Randich, S.;
Sartoretti, P.; Soubiran, C.; Tanga, P.; Walton, N. A.; Bailer-Jones,
C. A. L.; Bastian, U.; Drimmel, R.; Jansen, F.; Katz, D.; Lattanzi,
M. G.; van Leeuwen, F.; Bakker, J.; Cacciari, C.; Castañeda, J.;
De Angeli, F.; Fabricius, C.; Fouesneau, M.; Frémat, Y.; Galluccio,
L.; Guerrier, A.; Heiter, U.; Masana, E.; Messineo, R.; Mowlavi, N.;
Nicolas, C.; Nienartowicz, K.; Pailler, F.; Panuzzo, P.; Riclet,
F.; Roux, W.; Seabroke, G. M.; Sordoørcit, R.; Thévenin, F.;
Gracia-Abril, G.; Portell, J.; Teyssier, D.; Altmann, M.; Andrae, R.;
Audard, M.; Bellas-Velidis, I.; Benson, K.; Berthier, J.; Blomme,
R.; Burgess, P. W.; Busonero, D.; Busso, G.; Cánovas, H.; Carry,
B.; Cellino, A.; Cheek, N.; Clementini, G.; Damerdji, Y.; Davidson,
M.; de Teodoro, P.; Nuñez Campos, M.; Delchambre, L.; Dell'Oro,
A.; Esquej, P.; Fernández-Hernández, J.; Fraile, E.; Garabato, D.;
García-Lario, P.; Gosset, E.; Haigron, R.; Halbwachs, J. -L.; Hambly,
N. C.; Harrison, D. L.; Hernández, J.; Hestroffer, D.; Hodgkin,
S. T.; Holl, B.; Janßen, K.; Jevardat de Fombelle, G.; Jordan,
S.; Krone-Martins, A.; Lanzafame, A. C.; Löffler, W.; Marchal, O.;
Marrese, P. M.; Moitinho, A.; Muinonen, K.; Osborne, P.; Pancino,
E.; Pauwels, T.; Recio-Blanco, A.; Reylé, C.; Riello, M.; Rimoldini,
L.; Roegiers, T.; Rybizki, J.; Sarro, L. M.; Siopis, C.; Smith, M.;
Sozzetti, A.; Utrilla, E.; van Leeuwen, M.; Abbas, U.; Ábrahám, P.;
Abreu Aramburu, A.; Aerts, C.; Aguado, J. J.; Ajaj, M.; Aldea-Montero,
F.; Altavilla, G.; Álvarez, M. A.; Alves, J.; Anders, F.; Anderson,
R. I.; Anglada Varela, E.; Antoja, T.; Baines, D.; Baker, S. G.;
Balaguer-Núñez, L.; Balbinot, E.; Balog, Z.; Barache, C.; Barbato,
D.; Barros, M.; Barstow, M. A.; Bartolomé, S.; Bassilana, J. -L.;
Bauchet, N.; Becciani, U.; Bellazzini, M.; Berihuete, A.; Bernet, M.;
Bertone, S.; Bianchi, L.; Binnenfeld, A.; Blanco-Cuaresma, S.; Blazere,
A.; Boch, T.; Bombrun, A.; Bossini, D.; Bouquillon, S.; Bragaglia, A.;
Bramante, L.; Breedt, E.; Bressan, A.; Brouillet, N.; Brugaletta, E.;
Bucciarelli, B.; Burlacu, A.; Butkevich, A. G.; Buzzi, R.; Caffau,
E.; Cancelliere, R.; Cantat-Gaudin, T.; Carballo, R.; Carlucci, T.;
Carnerero, M. I.; Carrasco, J. M.; Casamiquela, L.; Castellani, M.;
Castro-Ginard, A.; Chaoul, L.; Charlot, P.; Chemin, L.; Chiaramida,
V.; Chiavassa, A.; Chornay, N.; Comoretto, G.; Contursi, G.; Cooper,
W. J.; Cornez, T.; Cowell, S.; Crifo, F.; Cropper, M.; Crosta, M.;
Crowley, C.; Dafonte, C.; Dapergolas, A.; David, M.; David, P.; de
Laverny, P.; De Luise, F.; De March, R.; De Ridder, J.; de Souza, R.;
de Torres, A.; del Peloso, E. F.; del Pozo, E.; Delbo, M.; Delgado,
A.; Delisle, J. -B.; Demouchy, C.; Dharmawardena, T. E.; Di Matteo,
P.; Diakite, S.; Diener, C.; Distefano, E.; Dolding, C.; Edvardsson,
B.; Enke, H.; Fabre, C.; Fabrizio, M.; Faigler, S.; Fedorets, G.;
Fernique, P.; Fienga, A.; Figueras, F.; Fournier, Y.; Fouron, C.;
Fragkoudi, F.; Gai, M.; Garcia-Gutierrez, A.; Garcia-Reinaldos, M.;
García-Torres, M.; Garofalo, A.; Gavel, A.; Gavras, P.; Gerlach,
E.; Geyer, R.; Giacobbe, P.; Gilmore, G.; Girona, S.; Giuffrida, G.;
Gomel, R.; Gomez, A.; González-Núñez, J.; González-Santamaría,
I.; González-Vidal, J. J.; Granvik, M.; Guillout, P.; Guiraud, J.;
Gutiérrez-Sánchez, R.; Guy, L. P.; Hatzidimitriou, D.; Hauser, M.;
Haywood, M.; Helmer, A.; Helmi, A.; Sarmiento, M. H.; Hidalgo, S. L.;
Hilger, T.; Hładczuk, N.; Hobbs, D.; Holland, G.; Huckle, H. E.;
Jardine, K.; Jasniewicz, G.; Jean-Antoine Piccolo, A.; Jiménez-Arranz,
Ó.; Jorissen, A.; Juaristi Campillo, J.; Julbe, F.; Karbevska, L.;
Kervella, P.; Khanna, S.; Kontizas, M.; Kordopatis, G.; Korn, A. J.;
Kóspál, Á; Kostrzewa-Rutkowska, Z.; Kruszyńska, K.; Kun, M.;
Laizeau, P.; Lambert, S.; Lanza, A. F.; Lasne, Y.; Le Campion, J. -F.;
Lebreton, Y.; Lebzelter, T.; Leccia, S.; Leclerc, N.; Lecoeur-Taibi,
I.; Liao, S.; Licata, E. L.; Lindstrøm, H. E. P.; Lister, T. A.;
Livanou, E.; Lobel, A.; Lorca, A.; Loup, C.; Madrero Pardo, P.;
Magdaleno Romeo, A.; Managau, S.; Mann, R. G.; Manteiga, M.; Marchant,
J. M.; Marconi, M.; Marcos, J.; Marcos Santos, M. M. S.; Marín Pina,
D.; Marinoni, S.; Marocco, F.; Marshall, D. J.; Polo, L. Martin;
Martín-Fleitas, J. M.; Marton, G.; Mary, N.; Masip, A.; Massari,
D.; Mastrobuono-Battisti, A.; Mazeh, T.; McMillan, P. J.; Messina,
S.; Michalik, D.; Millar, N. R.; Mints, A.; Molina, D.; Molinaro, R.;
Molnár, L.; Monari, G.; Monguió, M.; Montegriffo, P.; Montero, A.;
Mor, R.; Mora, A.; Morbidelli, R.; Morel, T.; Morris, D.; Muraveva, T.;
Murphy, C. P.; Musella, I.; Nagy, Z.; Noval, L.; Ocaña, F.; Ogden, A.;
Ordenovic, C.; Osinde, J. O.; Pagani, C.; Pagano, I.; Palaversa, L.;
Palicio, P. A.; Pallas-Quintela, L.; Panahi, A.; Payne-Wardenaar, S.;
Peñalosa Esteller, X.; Penttilä, A.; Pichon, B.; Piersimoni, A. M.;
Pineau, F. -X.; Plachy, E.; Plum, G.; Poggio, E.; Prša, A.; Pulone,
L.; Racero, E.; Ragaini, S.; Rainer, M.; Raiteri, C. M.; Rambaux, N.;
Ramos, P.; Ramos-Lerate, M.; Re Fiorentin, P.; Regibo, S.; Richards,
P. J.; Rios Diaz, C.; Ripepi, V.; Riva, A.; Rix, H. -W.; Rixon, G.;
Robichon, N.; Robin, A. C.; Robin, C.; Roelens, M.; Rogues, H. R. O.;
Rohrbasser, L.; Romero-Gómez, M.; Rowell, N.; Royer, F.; Ruz Mieres,
D.; Rybicki, K. A.; Sadowski, G.; Sáez Núñez, A.; Sagristà Sellés,
A.; Sahlmann, J.; Salguero, E.; Samaras, N.; Sanchez Gimenez, V.;
Sanna, N.; Santoveña, R.; Sarasso, M.; Schultheis, M.; Sciacca, E.;
Segol, M.; Segovia, J. C.; Ségransan, D.; Semeux, D.; Shahaf, S.;
Siddiqui, H. I.; Siebert, A.; Siltala, L.; Silvelo, A.; Slezak, E.;
Slezak, I.; Smart, R. L.; Snaith, O. N.; Solano, E.; Solitro, F.;
Souami, D.; Souchay, J.; Spagna, A.; Spina, L.; Spoto, F.; Steele,
I. A.; Steidelmüller, H.; Stephenson, C. A.; Süveges, M.; Surdej,
J.; Szabados, L.; Szegedi-Elek, E.; Taris, F.; Taylo, M. B.; Teixeira,
R.; Tolomei, L.; Tonello, N.; Torra, F.; Torra, J.; Torralba Elipe,
G.; Trabucchi, M.; Tsounis, A. T.; Turon, C.; Ulla, A.; Unger, N.;
Vaillant, M. V.; van Dillen, E.; van Reeven, W.; Vanel, O.; Vecchiato,
A.; Viala, Y.; Vicente, D.; Voutsinas, S.; Weiler, M.; Wevers, T.;
Wyrzykowski, L.; Yoldas, A.; Yvard, P.; Zhao, H.; Zorec, J.; Zucker,
S.; Zwitter, T.
Bibcode: 2022arXiv220800211G
Altcode:
We present the third data release of the European Space Agency's Gaia
mission, GDR3. The GDR3 catalogue is the outcome of the processing
of raw data collected with the Gaia instruments during the first
34 months of the mission by the Gaia Data Processing and Analysis
Consortium. The GDR3 catalogue contains the same source list, celestial
positions, proper motions, parallaxes, and broad band photometry in
the G, G$_{BP}$, and G$_{RP}$ pass-bands already present in the Early
Third Data Release. GDR3 introduces an impressive wealth of new data
products. More than 33 million objects in the ranges $G_{rvs} < 14$
and $3100 <T_{eff} <14500 $, have new determinations of their
mean radial velocities based on data collected by Gaia. We provide
G$_{rvs}$ magnitudes for most sources with radial velocities, and a
line broadening parameter is listed for a subset of these. Mean Gaia
spectra are made available to the community. The GDR3 catalogue includes
about 1 million mean spectra from the radial velocity spectrometer,
and about 220 million low-resolution blue and red prism photometer
BPRP mean spectra. The results of the analysis of epoch photometry are
provided for some 10 million sources across 24 variability types. GDR3
includes astrophysical parameters and source class probabilities for
about 470 million and 1500 million sources, respectively, including
stars, galaxies, and quasars. Orbital elements and trend parameters are
provided for some $800\,000$ astrometric, spectroscopic and eclipsing
binaries. More than $150\,000$ Solar System objects, including new
discoveries, with preliminary orbital solutions and individual epoch
observations are part of this release. Reflectance spectra derived
from the epoch BPRP spectral data are published for about 60\,000
asteroids. Finally, an additional data set is provided, namely the
Gaia Andromeda Photometric Survey (abridged)
Title: Gaia Data Release 3: Mapping the asymmetric disc of the
Milky Way
Authors: Gaia Collaboration; Drimmel, R.; Romero-Gomez, M.; Chemin,
L.; Ramos, P.; Poggio, E.; Ripepi, V.; Andrae, R.; Blomme, R.;
Cantat-Gaudin, T.; Castro-Ginard, A.; Clementini, G.; Figueras,
F.; Fouesneau, M.; Fremat, Y.; Jardine, K.; Khanna, S.; Lobel, A.;
Marshall, D. J.; Muraveva, T.; Brown, A. G. A.; Vallenari, A.; Prusti,
T.; de Bruijne, J. H. J.; Arenou, F.; Babusiaux, C.; Biermann, M.;
Creevey, O. L.; Ducourant, C.; Evans, D. W.; Eyer, L.; Guerra, R.;
Hutton, A.; Jordi, C.; Klioner, S. A.; Lammers, U. L.; Lindegren,
L.; Luri, X.; Mignard, F.; Panem, C.; Pourbaix, D.; Randich, S.;
Sartoretti, P.; Soubiran, C.; Tanga, P.; Walton, N. A.; Bailer-Jones,
C. A. L.; Bastian, U.; Jansen, F.; Katz, D.; Lattanzi, M. G.; van
Leeuwen, F.; Bakker, J.; Cacciari, C.; Castañeda, J.; De Angeli, F.;
Fabricius, C.; Galluccio, L.; Guerrier, A.; Heiter, U.; Masana, E.;
Messineo, R.; Mowlavi, N.; Nicolas, C.; Nienartowicz, K.; Pailler, F.;
Panuzzo, P.; Riclet, F.; Roux, W.; Seabroke, G. M.; Sordoørcit, R.;
Thévenin, F.; Gracia-Abril, G.; Portell, J.; Teyssier, D.; Altmann,
M.; Audard, M.; Bellas-Velidis, I.; Benson, K.; Berthier, J.; Burgess,
P. W.; Busonero, D.; Busso, G.; Cánovas, H.; Carry, B.; Cellino, A.;
Cheek, N.; Damerdji, Y.; Davidson, M.; de Teodoro, P.; Nuñez Campos,
M.; Delchambre, L.; Dell'Oro, A.; Esquej, P.; Fernández-Hernández,
J.; Fraile, E.; Garabato, D.; García-Lario, P.; Gosset, E.; Haigron,
R.; Halbwachs, J. -L.; Hambly, N. C.; Harrison, D. L.; Hernández,
J.; Hestroffer, D.; Hodgkin, S. T.; Holl, B.; Janßen, K.; Jevardat
de Fombelle, G.; Jordan, S.; Krone-Martins, A.; Lanzafame, A. C.;
Löffler, W.; Marchal, O.; Marrese, P. M.; Moitinho, A.; Muinonen, K.;
Osborne, P.; Pancino, E.; Pauwels, T.; Recio-Blanco, A.; Reylé, C.;
Riello, M.; Rimoldini, L.; Roegiers, T.; Rybizki, J.; Sarro, L. M.;
Siopis, C.; Smith, M.; Sozzetti, A.; Utrilla, E.; van Leeuwen, M.;
Abbas, U.; Ábrahám, P.; Abreu Aramburu, A.; Aerts, C.; Aguado,
J. J.; Ajaj, M.; Aldea-Montero, F.; Altavilla, G.; Álvarez, M. A.;
Alves, J.; Anders, F.; Anderson, R. I.; Anglada Varela, E.; Antoja, T.;
Baines, D.; Baker, S. G.; Balaguer-Núñez, L.; Balbinot, E.; Balog,
Z.; Barache, C.; Barbato, D.; Barros, M.; Barstow, M. A.; Bartolomé,
S.; Bassilana, J. -L.; Bauchet, N.; Becciani, U.; Bellazzini, M.;
Berihuete, A.; Bernet, M.; Bertone, S.; Bianchi, L.; Binnenfeld, A.;
Blanco-Cuaresma, S.; Blazere, A.; Boch, T.; Bombrun, A.; Bossini, D.;
Bouquillon, S.; Bragaglia, A.; Bramante, L.; Breedt, E.; Bressan, A.;
Brouillet, N.; Brugaletta, E.; Bucciarelli, B.; Burlacu, A.; Butkevich,
A. G.; Buzzi, R.; Caffau, E.; Cancelliere, R.; Carballo, R.; Carlucci,
T.; Carnerero, M. I.; Carrasco, J. M.; Casamiquela, L.; Castellani,
M.; Chaoul, L.; Charlot, P.; Chiaramida, V.; Chiavassa, A.; Chornay,
N.; Comoretto, G.; Contursi, G.; Cooper, W. J.; Cornez, T.; Cowell,
S.; Crifo, F.; Cropper, M.; Crosta, M.; Crowley, C.; Dafonte, C.;
Dapergolas, A.; David, M.; David, P.; de Laverny, P.; De Luise, F.;
De March, R.; De Ridder, J.; de Souza, R.; de Torres, A.; del Peloso,
E. F.; del Pozo, E.; Delbo, M.; Delgado, A.; Delisle, J. -B.; Demouchy,
C.; Dharmawardena, T. E.; Di Matteo, P.; Diakite, S.; Diener, C.;
Distefano, E.; Dolding, C.; Edvardsson, B.; Enke, H.; Fabre, C.;
Fabrizio, M.; Faigler, S.; Fedorets, G.; Fernique, P.; Fienga, A.;
Fournier, Y.; Fouron, C.; Fragkoudi, F.; Gai, M.; Garcia-Gutierrez,
A.; Garcia-Reinaldos, M.; García-Torres, M.; Garofalo, A.; Gavel,
A.; Gavras, P.; Gerlach, E.; Geyer, R.; Giacobbe, P.; Gilmore, G.;
Girona, S.; Giuffrida, G.; Gomel, R.; Gomez, A.; González-Núñez,
J.; González-Santamaría, I.; González-Vidal, J. J.; Granvik,
M.; Guillout, P.; Guiraud, J.; Gutiérrez-Sánchez, R.; Guy, L. P.;
Hatzidimitriou, D.; Hauser, M.; Haywood, M.; Helmer, A.; Helmi, A.;
Sarmiento, M. H.; Hidalgo, S. L.; Hilger, T.; Hładczuk, N.; Hobbs,
D.; Holland, G.; Huckle, H. E.; Jasniewicz, G.; Jean-Antoine Piccolo,
A.; Jiménez-Arranz, Ó.; Jorissen, A.; Juaristi Campillo, J.; Julbe,
F.; Karbevska, L.; Kervella, P.; Kontizas, M.; Kordopatis, G.; Korn,
A. J.; Kóspál, Á; Kostrzewa-Rutkowska, Z.; Kruszyńska, K.; Kun, M.;
Laizeau, P.; Lambert, S.; Lanza, A. F.; Lasne, Y.; Le Campion, J. -F.;
Lebreton, Y.; Lebzelter, T.; Leccia, S.; Leclerc, N.; Lecoeur-Taibi,
I.; Liao, S.; Licata, E. L.; Lindstrøm, H. E. P.; Lister, T. A.;
Livanou, E.; Lorca, A.; Loup, C.; Madrero Pardo, P.; Magdaleno Romeo,
A.; Managau, S.; Mann, R. G.; Manteiga, M.; Marchant, J. M.; Marconi,
M.; Marcos, J.; Marcos Santos, M. M. S.; Marín Pina, D.; Marinoni,
S.; Marocco, F.; Polo, L. Martin; Martín-Fleitas, J. M.; Marton, G.;
Mary, N.; Masip, A.; Massari, D.; Mastrobuono-Battisti, A.; Mazeh,
T.; McMillan, P. J.; Messina, S.; Michalik, D.; Millar, N. R.; Mints,
A.; Molina, D.; Molinaro, R.; Molnár, L.; Monari, G.; Monguió,
M.; Montegriffo, P.; Montero, A.; Mor, R.; Mora, A.; Morbidelli, R.;
Morel, T.; Morris, D.; Murphy, C. P.; Musella, I.; Nagy, Z.; Noval,
L.; Ocaña, F.; Ogden, A.; Ordenovic, C.; Osinde, J. O.; Pagani, C.;
Pagano, I.; Palaversa, L.; Palicio, P. A.; Pallas-Quintela, L.; Panahi,
A.; Payne-Wardenaar, S.; Peñalosa Esteller, X.; Penttilä, A.; Pichon,
B.; Piersimoni, A. M.; Pineau, F. -X.; Plachy, E.; Plum, G.; Prša,
A.; Pulone, L.; Racero, E.; Ragaini, S.; Rainer, M.; Raiteri, C. M.;
Rambaux, N.; Ramos-Lerate, M.; Re Fiorentin, P.; Regibo, S.; Richards,
P. J.; Rios Diaz, C.; Riva, A.; Rix, H. -W.; Rixon, G.; Robichon, N.;
Robin, A. C.; Robin, C.; Roelens, M.; Rogues, H. R. O.; Rohrbasser,
L.; Rowell, N.; Royer, F.; Ruz Mieres, D.; Rybicki, K. A.; Sadowski,
G.; Sáez Núñez, A.; Sagristà Sellés, A.; Sahlmann, J.; Salguero,
E.; Samaras, N.; Sanchez Gimenez, V.; Sanna, N.; Santoveña, R.;
Sarasso, M.; Schultheis, M.; Sciacca, E.; Segol, M.; Segovia, J. C.;
Ségransan, D.; Semeux, D.; Shahaf, S.; Siddiqui, H. I.; Siebert,
A.; Siltala, L.; Silvelo, A.; Slezak, E.; Slezak, I.; Smart, R. L.;
Snaith, O. N.; Solano, E.; Solitro, F.; Souami, D.; Souchay, J.;
Spagna, A.; Spina, L.; Spoto, F.; Steele, I. A.; Steidelmüller,
H.; Stephenson, C. A.; Süveges, M.; Surdej, J.; Szabados, L.;
Szegedi-Elek, E.; Taris, F.; Taylo, M. B.; Teixeira, R.; Tolomei,
L.; Tonello, N.; Torra, F.; Torra, J.; Torralba Elipe, G.; Trabucchi,
M.; Tsounis, A. T.; Turon, C.; Ulla, A.; Unger, N.; Vaillant, M. V.;
van Dillen, E.; van Reeven, W.; Vanel, O.; Vecchiato, A.; Viala, Y.;
Vicente, D.; Voutsinas, S.; Weiler, M.; Wevers, T.; Wyrzykowski, L.;
Yoldas, A.; Yvard, P.; Zhao, H.; Zorec, J.; Zucker, S.; Zwitter, T.
Bibcode: 2022arXiv220606207G
Altcode:
With the most recent Gaia data release the number of sources with
complete 6D phase space information (position and velocity) has
increased to well over 33 million stars, while stellar astrophysical
parameters are provided for more than 470 million sources, in addition
to the identification of over 11 million variable stars. Using the
astrophysical parameters and variability classifications provided
in Gaia DR3, we select various stellar populations to explore and
identify non-axisymmetric features in the disc of the Milky Way in
both configuration and velocity space. Using more about 580 thousand
sources identified as hot OB stars, together with 988 known open
clusters younger than 100 million years, we map the spiral structure
associated with star formation 4-5 kpc from the Sun. We select over 2800
Classical Cepheids younger than 200 million years, which show spiral
features extending as far as 10 kpc from the Sun in the outer disc. We
also identify more than 8.7 million sources on the red giant branch
(RGB), of which 5.7 million have line-of-sight velocities, allowing
the velocity field of the Milky Way to be mapped as far as 8 kpc from
the Sun, including the inner disc. The spiral structure revealed by
the young populations is consistent with recent results using Gaia
EDR3 astrometry and source lists based on near infrared photometry,
showing the Local (Orion) arm to be at least 8 kpc long, and an outer
arm consistent with what is seen in HI surveys, which seems to be a
continuation of the Perseus arm into the third quadrant. Meanwhile,
the subset of RGB stars with velocities clearly reveals the large scale
kinematic signature of the bar in the inner disc, as well as evidence
of streaming motions in the outer disc that might be associated with
spiral arms or bar resonances. (abridged)
Title: Gaia Data Release 3: The extragalactic content
Authors: Gaia Collaboration; Bailer-Jones, C. A. L.; Teyssier, D.;
Delchambre, L.; Ducourant, C.; Garabato, D.; Hatzidimitriou, D.;
Klioner, S. A.; Rimoldini, L.; Bellas-Velidis, I.; Carballo, R.;
Carnerero, M. I.; Diener, C.; Fouesneau, M.; Galluccio, L.; Gavras,
P.; Krone-Martins, A.; Raiteri, C. M.; Teixeira, R.; Brown, A. G. A.;
Vallenari, A.; Prusti, T.; de Bruijne, J. H. J.; Arenou, F.; Babusiaux,
C.; Biermann, M.; Creevey, O. L.; Evans, D. W.; Eyer, L.; Guerra,
R.; Hutton, A.; Jordi, C.; Lammers, U. L.; Lindegren, L.; Luri, X.;
Mignard, F.; Panem, C.; Pourbaix, D.; Randich, S.; Sartoretti, P.;
Soubiran, C.; Tanga, P.; Walton, N. A.; Bastian, U.; Drimmel, R.;
Jansen, F.; Katz, D.; Lattanzi, M. G.; van Leeuwen, F.; Bakker, J.;
Cacciari, C.; Castañeda, J.; De Angeli, F.; Fabricius, C.; Frémat,
Y.; Guerrier, A.; Heiter, U.; Masana, E.; Messineo, R.; Mowlavi, N.;
Nicolas, C.; Nienartowicz, K.; Pailler, F.; Panuzzo, P.; Riclet, F.;
Roux, W.; Seabroke, G. M.; Sordo, R.; Thévenin, F.; Gracia-Abril, G.;
Portell, J.; Altmann, M.; Andrae, R.; Audard, M.; Benson, K.; Berthier,
J.; Blomme, R.; Burgess, P. W.; Busonero, D.; Busso, G.; Cánovas,
H.; Carry, B.; Cellino, A.; Cheek, N.; Clementini, G.; Damerdji,
Y.; Davidson, M.; de Teodoro, P.; Nuñez Campos, M.; Dell'Oro, A.;
Esquej, P.; Fernández-Hernández, J.; Fraile, E.; García-Lario, P.;
Gosset, E.; Haigron, R.; Halbwachs, J. -L.; Hambly, N. C.; Harrison,
D. L.; Hernández, J.; Hestroffer, D.; Hodgkin, S. T.; Holl, B.;
Janßen, K.; Jevardat de Fombelle, G.; Jordan, S.; Lanzafame, A. C.;
Löffler, W.; Marchal, O.; Marrese, P. M.; Moitinho, A.; Muinonen,
K.; Osborne, P.; Pancino, E.; Pauwels, T.; Recio-Blanco, A.; Reylé,
C.; Riello, M.; Roegiers, T.; Rybizki, J.; Sarro, L. M.; Siopis, C.;
Smith, M.; Sozzetti, A.; Utrilla, E.; van Leeuwen, M.; Abbas, U.;
Ábrahám, P.; Abreu Aramburu, A.; Aerts, C.; Aguado, J. J.; Ajaj,
M.; Aldea-Montero, F.; Altavilla, G.; Álvarez, M. A.; Alves, J.;
Anderson, R. I.; Anglada Varela, E.; Antoja, T.; Baines, D.; Baker,
S. G.; Balaguer-Núñez, L.; Balbinot, E.; Balog, Z.; Barache, C.;
Barbato, D.; Barros, M.; Barstow, M. A.; Bartolomé, S.; Bassilana,
J. -L.; Bauchet, N.; Becciani, U.; Bellazzini, M.; Berihuete, A.;
Bernet, M.; Bertone, S.; Bianchi, L.; Binnenfeld, A.; Blanco-Cuaresma,
S.; Boch, T.; Bombrun, A.; Bossini, D.; Bouquillon, S.; Bragaglia, A.;
Bramante, L.; Breedt, E.; Bressan, A.; Brouillet, N.; Brugaletta, E.;
Bucciarelli, B.; Burlacu, A.; Butkevich, A. G.; Buzzi, R.; Caffau,
E.; Cancelliere, R.; Cantat-Gaudin, T.; Carlucci, T.; Carrasco,
J. M.; Casamiquela, L.; Castellani, M.; Castro-Ginard, A.; Chaoul,
L.; Charlot, P.; Chemin, L.; Chiaramida, V.; Chiavassa, A.; Chornay,
N.; Comoretto, G.; Contursi, G.; Cooper, W. J.; Cornez, T.; Cowell,
S.; Crifo, F.; Cropper, M.; Crosta, M.; Crowley, C.; Dafonte, C.;
Dapergolas, A.; David, P.; de Laverny, P.; De Luise, F.; De March,
R.; De Ridder, J.; de Souza, R.; de Torres, A.; del Peloso, E. F.;
del Pozo, E.; Delbo, M.; Delgado, A.; Delisle, J. -B.; Demouchy, C.;
Dharmawardena, T. E.; Diakite, S.; Distefano, E.; Dolding, C.; Enke,
H.; Fabre, C.; Fabrizio, M.; Faigler, S.; Fedorets, G.; Fernique,
P.; Figueras, F.; Fournier, Y.; Fouron, C.; Fragkoudi, F.; Gai,
M.; Garcia-Gutierrez, A.; Garcia-Reinaldos, M.; García-Torres, M.;
Garofalo, A.; Gavel, A.; Gerlach, E.; Geyer, R.; Giacobbe, P.; Gilmore,
G.; Girona, S.; Giuffrida, G.; Gomel, R.; Gomez, A.; González-Núñez,
J.; González-Santamaría, I.; González-Vidal, J. J.; Granvik,
M.; Guillout, P.; Guiraud, J.; Gutiérrez-Sánchez, R.; Guy, L. P.;
Hauser, M.; Haywood, M.; Helmer, A.; Helmi, A.; Sarmiento, M. H.;
Hidalgo, S. L.; Hładczuk, N.; Hobbs, D.; Holland, G.; Huckle, H. E.;
Jardine, K.; Jasniewicz, G.; Jean-Antoine Piccolo, A.; Jiménez-Arranz,
Ó.; Juaristi Campillo, J.; Julbe, F.; Karbevska, L.; Kervella, P.;
Khanna, S.; Kontizas, M.; Kordopatis, G.; Korn, A. J.; Kóspál,
Á; Kostrzewa-Rutkowska, Z.; Kruszyńska, K.; Kun, M.; Laizeau, P.;
Lambert, S.; Lanza, A. F.; Lasne, Y.; Le Campion, J. -F.; Lebreton,
Y.; Lebzelter, T.; Leccia, S.; Leclerc, N.; Lecoeur-Taibi, I.; Liao,
S.; Licata, E. L.; Lindstrøm, H. E. P.; Lister, T. A.; Livanou, E.;
Lobel, A.; Lorca, A.; Loup, C.; Madrero Pardo, P.; Magdaleno Romeo,
A.; Managau, S.; Mann, R. G.; Manteiga, M.; Marchant, J. M.; Marconi,
M.; Marcos, J.; Marcos Santos, M. M. S.; Marín Pina, D.; Marinoni, S.;
Marocco, F.; Marshall, D. J.; Polo, L. Martin; Martín-Fleitas, J. M.;
Marton, G.; Mary, N.; Masip, A.; Massari, D.; Mastrobuono-Battisti,
A.; Mazeh, T.; McMillan, P. J.; Messina, S.; Michalik, D.; Millar,
N. R.; Mints, A.; Molina, D.; Molinaro, R.; Molnár, L.; Monari,
G.; Monguió, M.; Montegriffo, P.; Montero, A.; Mor, R.; Mora, A.;
Morbidelli, R.; Morel, T.; Morris, D.; Muraveva, T.; Murphy, C. P.;
Musella, I.; Nagy, Z.; Noval, L.; Ocaña, F.; Ogden, A.; Ordenovic,
C.; Osinde, J. O.; Pagani, C.; Pagano, I.; Palaversa, L.; Palicio,
P. A.; Pallas-Quintela, L.; Panahi, A.; Payne-Wardenaar, S.; Peñalosa
Esteller, X.; Penttilä, A.; Pichon, B.; Piersimoni, A. M.; Pineau,
F. -X.; Plachy, E.; Plum, G.; Poggio, E.; Prša, A.; Pulone, L.;
Racero, E.; Ragaini, S.; Rainer, M.; Ramos, P.; Ramos-Lerate, M.; Re
Fiorentin, P.; Regibo, S.; Richards, P. J.; Rios Diaz, C.; Ripepi, V.;
Riva, A.; Rix, H. -W.; Rixon, G.; Robichon, N.; Robin, A. C.; Robin,
C.; Roelens, M.; Rogues, H. R. O.; Rohrbasser, L.; Romero-Gómez, M.;
Rowell, N.; Royer, F.; Ruz Mieres, D.; Rybicki, K. A.; Sadowski, G.;
Sáez Núñez, A.; Sagristà Sellés, A.; Sahlmann, J.; Salguero, E.;
Samaras, N.; Sanchez Gimenez, V.; Sanna, N.; Santoveña, R.; Sarasso,
M.; Schultheis, M. S.; Sciacca, E.; Segol, M.; Segovia, J. C.;
Ségransan, D.; Semeux, D.; Shahaf, S.; Siddiqui, H. I.; Siebert,
A.; Siltala, L.; Silvelo, A.; Slezak, E.; Slezak, I.; Smart, R. L.;
Snaith, O. N.; Solano, E.; Solitro, F.; Souami, D.; Souchay, J.;
Spagna, A.; Spina, L.; Spoto, F.; Steele, I. A.; Steidelmüller,
H.; Stephenson, C. A.; Süveges, M.; Surdej, J.; Szabados, L.;
Szegedi-Elek, E.; Taris, F.; Taylor, M. B.; Tolomei, L.; Tonello,
N.; Torra, F.; Torra, J.; Torralba Elipe, G.; Trabucchi, M.; Tsounis,
A. T.; Turon, C.; Ulla, A.; Unger, N.; Vaillant, M. V.; van Dillen,
E.; van Reeven, W.; Vanel, O.; Vecchiato, A.; Viala, Y.; Vicente, D.;
Voutsinas, S.; Weiler, M.; Wevers, T.; Wyrzykowski, Ł.; Yoldas, A.;
Yvard, P.; Zhao, H.; Zorec, J.; Zucker, S.; Zwitter, T.
Bibcode: 2022arXiv220605681G
Altcode:
The Gaia Galactic survey mission is designed and optimized to obtain
astrometry, photometry, and spectroscopy of nearly two billion stars in
our Galaxy. Yet as an all-sky multi-epoch survey, Gaia also observes
several million extragalactic objects down to a magnitude of G~21
mag. Due to the nature of the Gaia onboard selection algorithms,
these are mostly point-source-like objects. Using data provided by
the satellite, we have identified quasar and galaxy candidates via
supervised machine learning methods, and estimate their redshifts using
the low resolution BP/RP spectra. We further characterise the surface
brightness profiles of host galaxies of quasars and of galaxies from
pre-defined input lists. Here we give an overview of the processing
of extragalactic objects, describe the data products in Gaia DR3,
and analyse their properties. Two integrated tables contain the main
results for a high completeness, but low purity (50-70%), set of
6.6 million candidate quasars and 4.8 million candidate galaxies. We
provide queries that select purer sub-samples of these containing 1.9
million probable quasars and 2.9 million probable galaxies (both 95%
purity). We also use high quality BP/RP spectra of 43 thousand high
probability quasars over the redshift range 0.05-4.36 to construct a
composite quasar spectrum spanning restframe wavelengths from 72-100 nm.
Title: Gaia Data Release 3: Reflectance spectra of Solar System
small bodies
Authors: Gaia Collaboration; Galluccio, L.; Delbo, M.; De Angeli, F.;
Pauwels, T.; Tanga, P.; Mignard, F.; Cellino, A.; Brown, A. G. A.;
Muinonen, K.; Penttila, A.; Jordan, S.; Vallenari, A.; Prusti,
T.; de Bruijne, J. H. J.; Arenou, F.; Babusiaux, C.; Biermann, M.;
Creevey, O. L.; Ducourant, C.; Evans, D. W.; Eyer, L.; Guerra, R.;
Hutton, A.; Jordi, C.; Klioner, S. A.; Lammers, U. L.; Lindegren,
L.; Luri, X.; Panem, C.; Pourbaix, D.; Randich, S.; Sartoretti, P.;
Soubiran, C.; Walton, N. A.; Bailer-Jones, C. A. L.; Bastian, U.;
Drimmel, R.; Jansen, F.; Katz, D.; Lattanzi, M. G.; van Leeuwen, F.;
Bakker, J.; Cacciari, C.; Castaneda, J.; Fabricius, C.; Fouesneau,
M.; Frémat, Y.; Guerrier, A.; Heiter, U.; Masana, E.; Messineo, R.;
Mowlavi, N.; Nicolas, C.; Nienartowicz, K.; Pailler, F.; Panuzzo,
P.; Riclet, F.; Roux, W.; Seabroke, G. M.; Sordo, R.; Thévenin, F.;
Gracia-Abril, G.; Portell, J.; Teyssier, D.; Altmann, M.; Andrae, R.;
Audard, M.; Bellas-Velidis, I.; Benson, K.; Berthier, J.; Blomme, R.;
Burgess, P. W.; Busonero, D.; Busso, G.; Cánovas, H.; Carry, B.;
Cheek, N.; Clementini, G.; Damerdji, Y.; Davidson, M.; de Teodoro,
P.; Nunez Campos, M.; Delchambre, L.; Dell Oro, A.; Esquej, P.;
Fernández-Hernández, J.; Fraile, E.; Garabato, D.; García-Lario,
P.; Gosset, E.; Haigron, R.; Halbwachs, J. -L.; Hambly, N. C.;
Harrison, D. L.; Hernández, J.; Hestroffer, D.; Hodgkin, S. T.;
Holl, B.; Janssen, K.; Jevardat de Fombelle, G.; Krone-Martins, A.;
Lanzafame, A. C.; Löffler, W.; Marchal, O.; Marrese, P. M.; Moitinho,
A.; Osborne, P.; Pancino, E.; Recio-Blanco, A.; Reylé, C.; Riello,
M.; Rimoldini, L.; Roegiers, T.; Rybizki, J.; Sarro, L. M.; Siopis,
C.; Smith, M.; Sozzetti, A.; Utrilla, E.; van Leeuwen, M.; Abbas, U.;
Ábrahám, P.; Abreu Aramburu, A.; Aerts, C.; Aguado, J. J.; Ajaj,
M.; Aldea-Montero, F.; Altavilla, G.; Álvarez, M. A.; Alves, J.;
Anderson, R. I.; Anglada Varela, E.; Antoja, T.; Baines, D.; Baker,
S. G.; Balaguer-Núnez, L.; Balbinot, E.; Balog, Z.; Barache, C.;
Barbato, D.; Barros, M.; Barstow, M. A.; Bartolomé, S.; Bassilana,
J. -L.; Bauchet, N.; Becciani, U.; Bellazzini, M.; Berihuete, A.;
Bernet, M.; Bertone, S.; Bianchi, L.; Binnenfeld, A.; Blanco-Cuaresma,
S.; Boch, T.; Bombrun, A.; Bossini, D.; Bouquillon, S.; Bragaglia, A.;
Bramante, L.; Breedt, E.; Bressan, A.; Brouillet, N.; Brugaletta, E.;
Bucciarelli, B.; Burlacu, A.; Butkevich, A. G.; Buzzi, R.; Caffau,
E.; Cancelliere, R.; Cantat-Gaudin, T.; Carballo, R.; Carlucci, T.;
Carnerero, M. I.; Carrasco, J. M.; Casamiquela, L.; Castellani, M.;
Castro-Ginard, A.; Chaoul, L.; Charlot, P.; Chemin, L.; Chiaramida,
V.; Chiavassa, A.; Chornay, N.; Comoretto, G.; Contursi, G.; Cooper,
W. J.; Cornez, T.; Cowell, S.; Crifo, F.; Cropper, M.; Crosta, M.;
Crowley, C.; Dafonte, C.; Dapergolas, A.; David, P.; de Laverny, P.;
De Luise, F.; De March, R.; De Ridder, J.; de Souza, R.; de Torres,
A.; del Peloso, E. F.; del Pozo, E.; Delgado, A.; Delisle, J. -B.;
Demouchy, C.; Dharmawardena, T. E.; Diakite, S.; Diener, C.; Distefano,
E.; Dolding, C.; Enke, H.; Fabre, C.; Fabrizio, M.; Faigler, S.;
Fedorets, G.; Fernique, P.; Figueras, F.; Fournier, Y.; Fouron, C.;
Fragkoudi, F.; Gai, M.; Garcia-Gutierrez, A.; Garcia-Reinaldos, M.;
García-Torres, M.; Garofalo, A.; Gavel, A.; Gavras, P.; Gerlach,
E.; Geyer, R.; Giacobbe, P.; Gilmore, G.; Girona, S.; Giuffrida, G.;
Gomel, R.; Gomez, A.; González-Núnez, J.; González-Santamaría,
I.; González-Vidal, J. J.; Granvik, M.; Guillout, P.; Guiraud, J.;
Gutiérrez-Sánchez, R.; Guy, L. P.; Hatzidimitriou, D.; Hauser,
M.; Haywood, M.; Helmer, A.; Helmi, A.; Sarmiento, M. H.; Hidalgo,
S. L.; Hadczuk, N.; Hobbs, D.; Holland, G.; Huckle, H. E.; Jardine,
K.; Jasniewicz, G.; Jean-Antoine Piccolo, A.; Jiménez-Arranz, Ó.;
Juaristi Campillo, J.; Julbe, F.; Karbevska, L.; Kervella, P.; Khanna,
S.; Kordopatis, G.; Korn, A. J.; Kospál, A; Kostrzewa-Rutkowska,
Z.; Kruszynska, K.; Kun, M.; Laizeau, P.; Lambert, S.; Lanza,
A. F.; Lasne, Y.; Le Campion, J. -F.; Lebreton, Y.; Lebzelter, T.;
Leccia, S.; Leclerc, N.; Lecoeur-Taibi, I.; Liao, S.; Licata, E. L.;
Lindstrom, H. E. P.; Lister, T. A.; Livanou, E.; Lobel, A.; Lorca,
A.; Loup, C.; Madrero Pardo, P.; Magdaleno Romeo, A.; Managau, S.;
Mann, R. G.; Manteiga, M.; Marchant, J. M.; Marconi, M.; Marcos, J.;
Marcos Santos, M. M. S.; Marín Pina, D.; Marinoni, S.; Marocco, F.;
Marshall, D. J.; Polo, L. Martin; Martín-Fleitas, J. M.; Marton, G.;
Mary, N.; Masip, A.; Massari, D.; Mastrobuono-Battisti, A.; Mazeh,
T.; McMillan, P. J.; Messina, S.; Michalik, D.; Millar, N. R.; Mints,
A.; Molina, D.; Molinaro, R.; Molnár, L.; Monari, G.; Monguió, M.;
Montegriffo, P.; Montero, A.; Mor, R.; Mora, A.; Morbidelli, R.; Morel,
T.; Morris, D.; Muraveva, T.; Murphy, C. P.; Musella, I.; Nagy, Z.;
Noval, L.; Ocana, F.; Ogden, A.; Ordenovic, C.; Osinde, J. O.; Pagani,
C.; Pagano, I.; Palaversa, L.; Palicio, P. A.; Pallas-Quintela, L.;
Panahi, A.; Payne-Wardenaar, S.; Penalosa Esteller, X.; Petit, J. -M.;
Pichon, B.; Piersimoni, A. M.; Pineau, F. -X.; Plachy, E.; Plum, G.;
Poggio, E.; Prsa, A.; Pulone, L.; Racero, E.; Ragaini, S.; Rainer, M.;
Raiteri, C. M.; Ramos, P.; Ramos-Lerate, M.; Re Fiorentin, P.; Regibo,
S.; Richards, P. J.; Rios Diaz, C.; Ripepi, V.; Riva, A.; Rix, H. -W.;
Rixon, G.; Robichon, N.; Robin, A. C.; Robin, C.; Roelens, M.; Rogues,
H. R. O.; Rohrbasser, L.; Romero-Gómez, M.; Rowell, N.; Royer, F.; Ruz
Mieres, D.; Rybicki, K. A.; Sadowski, G.; Sáez Núnez, A.; Sagristà
Sellés, A.; Sahlmann, J.; Salguero, E.; Samaras, N.; Sanchez Gimenez,
V.; Sanna, N.; Santovena, R.; Sarasso, M.; Schultheis, M.; Sciacca,
E.; Segol, M.; Segovia, J. C.; Ségransan, D.; Semeux, D.; Shahaf,
S.; Siddiqui, H. I.; Siebert, A.; Siltala, L.; Silvelo, A.; Slezak,
E.; Slezak, I.; Smart, R. L.; Snaith, O. N.; Solano, E.; Solitro,
F.; Souami, D.; Souchay, J.; Spagna, A.; Spina, L.; Spoto, F.;
Steele, I. A.; Steidelmüller, H.; Stephenson, C. A.; Süveges,
M.; Surdej, J.; Szabados, L.; Szegedi-Elek, E.; Taris, F.; Taylor,
M. B.; Teixeira, R.; Tolomei, L.; Tonello, N.; Torra, F.; Torra, J.;
Torralba Elipe, G.; Trabucchi, M.; Tsounis, A. T.; Turon, C.; Ulla,
A.; Unger, N.; Vaillant, M. V.; van Dillen, E.; van Reeven, W.; Vanel,
O.; Vecchiato, A.; Viala, Y.; Vicente, D.; Voutsinas, S.; Weiler, M.;
Wevers, T.; Wyrzykowski, L.; Yoldas, A.; Yvard, P.; Zhao, H.; Zorec,
J.; Zucker, S.; Zwitter, T.
Bibcode: 2022arXiv220612174G
Altcode:
The Gaia mission of the European Space Agency (ESA) has been routinely
observing Solar System objects (SSOs) since the beginning of its
operations in August 2014. The Gaia data release three (DR3) includes,
for the first time, the mean reflectance spectra of a selected sample of
60 518 SSOs, primarily asteroids, observed between August 5, 2014, and
May 28, 2017. Each reflectance spectrum was derived from measurements
obtained by means of the Blue and Red photometers (BP/RP), which were
binned in 16 discrete wavelength bands. We describe the processing
of the Gaia spectral data of SSOs, explaining both the criteria used
to select the subset of asteroid spectra published in Gaia DR3,
and the different steps of our internal validation procedures. In
order to further assess the quality of Gaia SSO reflectance spectra,
we carried out external validation against SSO reflectance spectra
obtained from ground-based and space-borne telescopes and available
in the literature. For each selected SSO, an epoch reflectance was
computed by dividing the calibrated spectrum observed by the BP/RP
at each transit on the focal plane by the mean spectrum of a solar
analogue. The latter was obtained by averaging the Gaia spectral
measurements of a selected sample of stars known to have very similar
spectra to that of the Sun. Finally, a mean of the epoch reflectance
spectra was calculated in 16 spectral bands for each SSO. The agreement
between Gaia mean reflectance spectra and those available in the
literature is good for bright SSOs, regardless of their taxonomic
spectral class. We identify an increase in the spectral slope of S-type
SSOs with increasing phase angle. Moreover, we show that the spectral
slope increases and the depth of the 1 um absorption band decreases
for increasing ages of S-type asteroid families.
Title: Gaia Data Release 3: A Golden Sample of Astrophysical
Parameters
Authors: Gaia Collaboration; Creevey, O. L.; Sarro, L. M.; Lobel, A.;
Pancino, E.; Andrae, R.; Smart, R. L.; Clementini, G.; Heiter, U.;
Korn, A. J.; Fouesneau, M.; Frémat, Y.; De Angeli, F.; Vallenari, A.;
Harrison, D. L.; Thévenin, F.; Reylé, C.; Sordo, R.; Garofalo, A.;
Brown, A. G. A.; Eyer, L.; Prusti, T.; de Bruijne, J. H. J.; Arenou,
F.; Babusiaux, C.; Biermann, M.; Ducourant, C.; Evans, D. W.; Guerra,
R.; Hutton, A.; Jordi, C.; Klioner, S. A.; Lammers, U. L.; Lindegren,
L.; Luri, X.; Mignard, F.; Panem, C.; Pourbaix, D.; Randich, S.;
Sartoretti, P.; Soubiran, C.; Tanga, P.; Walton, N. A.; Bailer-Jones,
C. A. L.; Bastian, U.; Drimmel, R.; Jansen, F.; Katz, D.; Lattanzi,
M. G.; van Leeuwen, F.; Bakker, J.; Cacciari, C.; Castañeda, J.;
Fabricius, C.; Galluccio, L.; Guerrier, A.; Masana, E.; Messineo, R.;
Mowlavi, N.; Nicolas, C.; Nienartowicz, K.; Pailler, F.; Panuzzo, P.;
Riclet, F.; Roux, W.; Seabroke, G. M.; Gracia-Abril, G.; Portell, J.;
Teyssier, D.; Altmann, M.; Audard, M.; Bellas-Velidis, I.; Benson,
K.; Berthier, J.; Blomme, R.; Burgess, P. W.; Busonero, D.; Busso,
G.; Cánovas, H.; Carry, B.; Cellino, A.; Cheek, N.; Damerdji, Y.;
Davidson, M.; de Teodoro, P.; Nuñez Campos, M.; Delchambre, L.;
Dell'Oro, A.; Esquej, P.; Fernández-Hernández, J.; Fraile, E.;
Garabato, D.; García-Lario, P.; Gosset, E.; Haigron, R.; Halbwachs,
J. -L.; Hambly, N. C.; Hernández, J.; Hestroffer, D.; Hodgkin,
S. T.; Holl, B.; Janßen, K.; Jevardat de Fombelle, G.; Jordan,
S.; Krone-Martins, A.; Lanzafame, A. C.; Löffler, W.; Marchal, O.;
Marrese, P. M.; Moitinho, A.; Muinonen, K.; Osborne, P.; Pauwels, T.;
Recio-Blanco, A.; Riello, M.; Rimoldini, L.; Roegiers, T.; Rybizki,
J.; Siopis, C.; Smith, M.; Sozzetti, A.; Utrilla, E.; van Leeuwen,
M.; Abbas, U.; Ábrahám, P.; Abreu Aramburu, A.; Aerts, C.; Aguado,
J. J.; Ajaj, M.; Aldea-Montero, F.; Altavilla, G.; Álvarez, M. A.;
Alves, J.; Anders, F.; Anderson, R. I.; Anglada Varela, E.; Antoja, T.;
Baines, D.; Baker, S. G.; Balaguer-Núñez, L.; Balbinot, E.; Balog,
Z.; Barache, C.; Barbato, D.; Barros, M.; Barstow, M. A.; Bartolomé,
S.; Bassilana, J. -L.; Bauchet, N.; Becciani, U.; Bellazzini, M.;
Berihuete, A.; Bernet, M.; Bertone, S.; Bianchi, L.; Binnenfeld, A.;
Blanco-Cuaresma, S.; Boch, T.; Bombrun, A.; Bossini, D.; Bouquillon,
S.; Bragaglia, A.; Bramante, L.; Breedt, E.; Bressan, A.; Brouillet,
N.; Brugaletta, E.; Bucciarelli, B.; Burlacu, A.; Butkevich, A. G.;
Buzzi, R.; Caffau, E.; Cancelliere, R.; Cantat-Gaudin, T.; Carballo,
R.; Carlucci, T.; Carnerero, M. I.; Carrasco, J. M.; Casamiquela,
L.; Castellani, M.; Castro-Ginard, A.; Chaoul, L.; Charlot, P.;
Chemin, L.; Chiaramida, V.; Chiavassa, A.; Chornay, N.; Comoretto,
G.; Contursi, G.; Cooper, W. J.; Cornez, T.; Cowell, S.; Crifo, F.;
Cropper, M.; Crosta, M.; Crowley, C.; Dafonte, C.; Dapergolas, A.;
David, P.; de Laverny, P.; De Luise, F.; De March, R.; De Ridder, J.;
de Souza, R.; de Torres, A.; del Peloso, E. F.; del Pozo, E.; Delbo,
M.; Delgado, A.; Delisle, J. -B.; Demouchy, C.; Dharmawardena, T. E.;
Di Matteo, P.; Diakite, S.; Diener, C.; Distefano, E.; Dolding, C.;
Enke, H.; Fabre, C.; Fabrizio, M.; Faigler, S.; Fedorets, G.; Fernique,
P.; Figueras, F.; Fournier, Y.; Fouron, C.; Fragkoudi, F.; Gai, M.;
Garcia-Gutierrez, A.; Garcia-Reinaldos, M.; García-Torres, M.; Gavel,
A.; Gavras, P.; Gerlach, E.; Geyer, R.; Giacobbe, P.; Gilmore, G.;
Girona, S.; Giuffrida, G.; Gomel, R.; Gomez, A.; González-Núñez,
J.; González-Santamaría, I.; González-Vidal, J. J.; Granvik, M.;
Guillout, P.; Guiraud, J.; Gutiérrez-Sánchez, R.; Guy, L. P.;
Hatzidimitriou, D.; Hauser, M.; Haywood, M.; Helmer, A.; Helmi,
A.; Sarmiento, M. H.; Hidalgo, S. L.; Hładczuk, N.; Hobbs, D.;
Holland, G.; Huckle, H. E.; Jardine, K.; Jasniewicz, G.; Jean-Antoine
Piccolo, A.; Jiménez-Arranz, Ó.; Juaristi Campillo, J.; Julbe, F.;
Karbevska, L.; Kervella, P.; Khanna, S.; Kordopatis, G.; Kóspál,
Á; Kostrzewa-Rutkowska, Z.; Kruszyńska, K.; Kun, M.; Laizeau, P.;
Lambert, S.; Lanza, A. F.; Lasne, Y.; Le Campion, J. -F.; Lebreton,
Y.; Lebzelter, T.; Leccia, S.; Leclerc, N.; Lecoeur-Taibi, I.; Liao,
S.; Licata, E. L.; Lindstrøm, H. E. P.; Lister, T. A.; Livanou, E.;
Lorca, A.; Loup, C.; Madrero Pardo, P.; Magdaleno Romeo, A.; Managau,
S.; Mann, R. G.; Manteiga, M.; Marchant, J. M.; Marconi, M.; Marcos,
J.; Marcos Santos, M. M. S.; Marín Pina, D.; Marinoni, S.; Marocco,
F.; Marshall, D. J.; Polo, L. Martin; Martín-Fleitas, J. M.; Marton,
G.; Mary, N.; Masip, A.; Massari, D.; Mastrobuono-Battisti, A.; Mazeh,
T.; McMillan, P. J.; Messina, S.; Michalik, D.; Millar, N. R.; Mints,
A.; Molina, D.; Molinaro, R.; Molnár, L.; Monari, G.; Monguió, M.;
Montegriffo, P.; Montero, A.; Mor, R.; Mora, A.; Morbidelli, R.; Morel,
T.; Morris, D.; Muraveva, T.; Murphy, C. P.; Musella, I.; Nagy, Z.;
Noval, L.; Ocaña, F.; Ogden, A.; Ordenovic, C.; Osinde, J. O.; Pagani,
C.; Pagano, I.; Palaversa, L.; Palicio, P. A.; Pallas-Quintela, L.;
Panahi, A.; Payne-Wardenaar, S.; Peñalosa Esteller, X.; Penttilä, A.;
Pichon, B.; Piersimoni, A. M.; Pineau, F. -X.; Plachy, E.; Plum, G.;
Poggio, E.; Prša, A.; Pulone, L.; Racero, E.; Ragaini, S.; Rainer,
M.; Raiteri, C. M.; Ramos, P.; Ramos-Lerate, M.; Re Fiorentin,
P.; Regibo, S.; Richards, P. J.; Rios Diaz, C.; Ripepi, V.; Riva,
A.; Rix, H. -W.; Rixon, G.; Robichon, N.; Robin, A. C.; Robin, C.;
Roelens, M.; Rogues, H. R. O.; Rohrbasser, L.; Romero-Gómez, M.;
Rowell, N.; Royer, F.; Ruz Mieres, D.; Rybicki, K. A.; Sadowski, G.;
Sáez Núñez, A.; Sagristà Sellés, A.; Sahlmann, J.; Salguero,
E.; Samaras, N.; Sanchez Gimenez, V.; Sanna, N.; Santoveña, R.;
Sarasso, M.; Schultheis, M.; Sciacca, E.; Segol, M.; Segovia, J. C.;
Ségransan, D.; Semeux, D.; Shahaf, S.; Siddiqui, H. I.; Siebert,
A.; Siltala, L.; Silvelo, A.; Slezak, E.; Slezak, I.; Snaith, O. N.;
Solano, E.; Solitro, F.; Souami, D.; Souchay, J.; Spagna, A.; Spina,
L.; Spoto, F.; Steele, I. A.; Steidelmüller, H.; Stephenson, C. A.;
Süveges, M.; Surdej, J.; Szabados, L.; Szegedi-Elek, E.; Taris,
F.; Taylor, M. B.; Teixeira, R.; Tolomei, L.; Tonello, N.; Torra,
F.; Torra, J.; Torralba Elipe, G.; Trabucchi, M.; Tsounis, A. T.;
Turon, C.; Ulla, A.; Unger, N.; Vaillant, M. V.; van Dillen, E.;
van Reeven, W.; Vanel, O.; Vecchiato, A.; Viala, Y.; Vicente, D.;
Voutsinas, S.; Weiler, M.; Wevers, T.; Wyrzykowski, Ł.; Yoldas, A.;
Yvard, P.; Zhao, H.; Zorec, J.; Zucker, S.; Zwitter, T.
Bibcode: 2022arXiv220605870G
Altcode:
Gaia Data Release 3 (DR3) provides a wealth of new data products for the
astronomical community to exploit, including astrophysical parameters
for a half billion stars. In this work we demonstrate the high
quality of these data products and illustrate their use in different
astrophysical contexts. We query the astrophysical parameter tables
along with other tables in Gaia DR3 to derive the samples of the stars
of interest. We validate our results by using the Gaia catalogue itself
and by comparison with external data. We have produced six homogeneous
samples of stars with high quality astrophysical parameters across
the HR diagram for the community to exploit. We first focus on three
samples that span a large parameter space: young massive disk stars
(~3M), FGKM spectral type stars (~3M), and UCDs (~20K). We provide
these sources along with additional information (either a flag or
complementary parameters) as tables that are made available in the
Gaia archive. We furthermore identify 15740 bone fide carbon stars,
5863 solar-analogues, and provide the first homogeneous set of stellar
parameters of the Spectro Photometric Standard Stars. We use a subset
of the OBA sample to illustrate its usefulness to analyse the Milky
Way rotation curve. We then use the properties of the FGKM stars to
analyse known exoplanet systems. We also analyse the ages of some
unseen UCD-companions to the FGKM stars. We additionally predict the
colours of the Sun in various passbands (Gaia, 2MASS, WISE) using the
solar-analogue sample.
Title: Gaia Data Release 3: Pulsations in main sequence OBAF-type
stars
Authors: Gaia Collaboration; De Ridder, J.; Ripepi, V.; Aerts, C.;
Palaversa, L.; Eyer, L.; Holl, B.; Audard, M.; Rimoldini, L.; Brown,
A. G. A.; Vallenari, A.; Prusti, T.; de Bruijne, J. H. J.; Arenou, F.;
Babusiaux, C.; Biermann, M.; Creevey, O. L.; Ducourant, C.; Evans,
D. W.; Guerra, R.; Hutton, A.; Jordi, C.; Klioner, S. A.; Lammers,
U. L.; Lindegren, L.; Luri, X.; Mignard, F.; Panem, C.; Pourbaix,
D.; Randich, S.; Sartoretti, P.; Soubiran, C.; Tanga, P.; Walton,
N. A.; Bailer-Jones, C. A. L.; Bastian, U.; Drimmel, R.; Jansen, F.;
Katz, D.; Lattanzi, M. G.; van Leeuwen, F.; Bakker, J.; Cacciari, C.;
Castañeda, J.; De Angeli, F.; Fabricius, C.; Fouesneau, M.; Frémat,
Y.; Galluccio, L.; Guerrier, A.; Heiter, U.; Masana, E.; Messineo,
R.; Mowlavi, N.; Nicolas, C.; Nienartowicz, K.; Pailler, F.; Panuzzo,
P.; Riclet, F.; Roux, W.; Seabroke, G. M.; Sordo, R.; Thévenin, F.;
Gracia-Abril, G.; Portell, J.; Teyssier, D.; Altmann, M.; Andrae, R.;
Bellas-Velidis, I.; Benson, K.; Berthier, J.; Blomme, R.; Burgess,
P. W.; Busonero, D.; Busso, G.; Cánovas, H.; Carry, B.; Cellino, A.;
Cheek, N.; Clementini, G.; Damerdji, Y.; Davidson, M.; de Teodoro,
P.; Nuñez Campos, M.; Delchambre, L.; Dell'Oro, A.; Esquej, P.;
Fernández-Hernández, J.; Fraile, E.; Garabato, D.; García-Lario, P.;
Gosset, E.; Haigron, R.; Halbwachs, J. -L.; Hambly, N. C.; Harrison,
D. L.; Hernández, J.; Hestroffer, D.; Hilger, T.; Hodgkin, S. T.;
Janßen, K.; Jevardat de Fombelle, G.; Jordan, S.; Krone-Martins, A.;
Lanzafame, A. C.; Löffler, W.; Marchal, O.; Marrese, P. M.; Moitinho,
A.; Muinonen, K.; Osborne, P.; Pancino, E.; Pauwels, T.; Recio-Blanco,
A.; Reylé, C.; Riello, M.; Roegiers, T.; Rybizki, J.; Sarro, L. M.;
Siopis, C.; Smith, M.; Sozzetti, A.; Utrilla, E.; van Leeuwen, M.;
Abbas, U.; Ábrahám, P.; Abreu Aramburu, A.; Aguado, J. J.; Ajaj,
M.; Aldea-Montero, F.; Altavilla, G.; Álvarez, M. A.; Alves, J.;
Anders, F.; Anderson, R. I.; Anglada Varela, E.; Antoja, T.; Baines,
D.; Baker, S. G.; Balaguer-Núñez, L.; Balbinot, E.; Balog, Z.;
Barache, C.; Barbato, D.; Barros, M.; Barstow, M. A.; Bartolomé,
S.; Bassilana, J. -L.; Bauchet, N.; Becciani, U.; Bellazzini, M.;
Berihuete, A.; Bernet, M.; Bertone, S.; Bianchi, L.; Binnenfeld, A.;
Blanco-Cuaresma, S.; Boch, T.; Bombrun, A.; Bossini, D.; Bouquillon,
S.; Bragaglia, A.; Bramante, L.; Breedt, E.; Bressan, A.; Brouillet,
N.; Brugaletta, E.; Bucciarelli, B.; Burlacu, A.; Butkevich, A. G.;
Buzzi, R.; Caffau, E.; Cancelliere, R.; Cantat-Gaudin, T.; Carballo,
R.; Carlucci, T.; Carnerero, M. I.; Carrasco, J. M.; Casamiquela,
L.; Castellani, M.; Castro-Ginard, A.; Chaoul, L.; Charlot, P.;
Chemin, L.; Chiaramida, V.; Chiavassa, A.; Chornay, N.; Comoretto,
G.; Contursi, G.; Cooper, W. J.; Cornez, T.; Cowell, S.; Crifo, F.;
Cropper, M.; Crosta, M.; Crowley, C.; Dafonte, C.; Dapergolas, A.;
David, P.; de Laverny, P.; De Luise, F.; De March, R.; de Souza, R.;
de Torres, A.; del Peloso, E. F.; del Pozo, E.; Delbo, M.; Delgado,
A.; Delisle, J. -B.; Demouchy, C.; Dharmawardena, T. E.; Diakite,
S.; Diener, C.; Distefano, E.; Dolding, C.; Enke, H.; Fabre, C.;
Fabrizio, M.; Faigler, S.; Fedorets, G.; Fernique, P.; Figueras, F.;
Fournier, Y.; Fouron, C.; Fragkoudi, F.; Gai, M.; Garcia-Gutierrez,
A.; Garcia-Reinaldos, M.; García-Torres, M.; Garofalo, A.; Gavel,
A.; Gavras, P.; Gerlach, E.; Geyer, R.; Giacobbe, P.; Gilmore, G.;
Girona, S.; Giuffrida, G.; Gomel, R.; Gomez, A.; González-Núñez,
J.; González-Santamaría, I.; González-Vidal, J. J.; Granvik,
M.; Guillout, P.; Guiraud, J.; Gutiérrez-Sánchez, R.; Guy, L. P.;
Hatzidimitriou, D.; Hauser, M.; Haywood, M.; Helmer, A.; Helmi, A.;
Sarmiento, M. H.; Hidalgo, S. L.; Hładczuk, N.; Hobbs, D.; Holland,
G.; Huckle, H. E.; Jardine, K.; Jasniewicz, G.; Jean-Antoine Piccolo,
A.; Jiménez-Arranz, Ó.; Juaristi Campillo, J.; Julbe, F.; Karbevska,
L.; Kervella, P.; Khanna, S.; Kordopatis, G.; Korn, A. J.; Kóspál,
Á; Kostrzewa-Rutkowska, Z.; Kruszyńska, K.; Kun, M.; Laizeau, P.;
Lambert, S.; Lanza, A. F.; Lasne, Y.; Le Campion, J. -F.; Lebreton,
Y.; Lebzelter, T.; Leccia, S.; Leclerc, N.; Lecoeur-Taibi, I.; Liao,
S.; Licata, E. L.; Lindstrøm, H. E. P.; Lister, T. A.; Livanou, E.;
Lobel, A.; Lorca, A.; Loup, C.; Madrero Pardo, P.; Magdaleno Romeo,
A.; Managau, S.; Mann, R. G.; Manteiga, M.; Marchant, J. M.; Marconi,
M.; Marcos, J.; Marcos Santos, M. M. S.; Marín Pina, D.; Marinoni, S.;
Marocco, F.; Marshall, D. J.; Polo, L. Martin; Martín-Fleitas, J. M.;
Marton, G.; Mary, N.; Masip, A.; Massari, D.; Mastrobuono-Battisti, A.;
Mazeh, T.; McMillan, P. J.; Messina, S.; Michalik, D.; Millar, N. R.;
Mints, A.; Molina, D.; Molinaro, R.; Molnár, L.; Monari, G.; Monguió,
M.; Montegriffo, P.; Montero, A.; Mor, R.; Mora, A.; Morbidelli,
R.; Morel, T.; Morris, D.; Muraveva, T.; Murphy, C. P.; Musella, I.;
Nagy, Z.; Noval, L.; Ocaña, F.; Ogden, A.; Ordenovic, C.; Osinde,
J. O.; Pagani, C.; Pagano, I.; Palicio, P. A.; Pallas-Quintela, L.;
Panahi, A.; Payne-Wardenaar, S.; Peñalosa Esteller, X.; Penttilä, A.;
Pichon, B.; Piersimoni, A. M.; Pineau, F. -X.; Plachy, E.; Plum, G.;
Poggio, E.; Prša, A.; Pulone, L.; Racero, E.; Ragaini, S.; Rainer, M.;
Raiteri, C. M.; Ramos, P.; Ramos-Lerate, M.; Re Fiorentin, P.; Regibo,
S.; Richards, P. J.; Rios Diaz, C.; Riva, A.; Rix, H. -W.; Rixon, G.;
Robichon, N.; Robin, A. C.; Robin, C.; Roelens, M.; Rogues, H. R. O.;
Rohrbasser, L.; Romero-Gómez, M.; Rowell, N.; Royer, F.; Ruz Mieres,
D.; Rybicki, K. A.; Sadowski, G.; Sáez Núñez, A.; Sagristà Sellés,
A.; Sahlmann, J.; Salguero, E.; Samaras, N.; Sanchez Gimenez, V.;
Sanna, N.; Santoveña, R.; Sarasso, M.; Schultheis, M.; Sciacca, E.;
Segol, M.; Segovia, J. C.; Ségransan, D.; Semeux, D.; Shahaf, S.;
Siddiqui, H. I.; Siebert, A.; Siltala, L.; Silvelo, A.; Slezak, E.;
Slezak, I.; Smart, R. L.; Snaith, O. N.; Solano, E.; Solitro, F.;
Souami, D.; Souchay, J.; Spagna, A.; Spina, L.; Spoto, F.; Steele,
I. A.; Steidelmüller, H.; Stephenson, C. A.; Süveges, M.; Surdej, J.;
Szabados, L.; Szegedi-Elek, E.; Taris, F.; Taylor, M. B.; Teixeira,
R.; Tolomei, L.; Tonello, N.; Torra, F.; Torra, J.; Torralba Elipe,
G.; Trabucchi, M.; Tsounis, A. T.; Turon, C.; Ulla, A.; Unger, N.;
Vaillant, M. V.; van Dillen, E.; van Reeven, W.; Vanel, O.; Vecchiato,
A.; Viala, Y.; Vicente, D.; Voutsinas, S.; Weiler, M.; Wevers, T.;
Wyrzykowski, Ł.; Yoldas, A.; Yvard, P.; Zhao, H.; Zorec, J.; Zucker,
S.; Zwitter, T.
Bibcode: 2022arXiv220606075G
Altcode:
The third Gaia data release provides photometric time series covering
34 months for about 10 million stars. For many of those stars, a
characterisation in Fourier space and their variability classification
are also provided. This paper focuses on intermediate- to high-mass
(IHM) main sequence pulsators M >= 1.3 Msun) of spectral types O,
B, A, or F, known as beta Cep, slowly pulsating B (SPB), delta Sct,
and gamma Dor stars. These stars are often multi-periodic and display
low amplitudes, making them challenging targets to analyse with sparse
time series. All datasets used in this analysis are part of the Gaia DR3
data release. The photometric time series were used to perform a Fourier
analysis, while the global astrophysical parameters necessary for
the empirical instability strips were taken from the Gaia DR3 gspphot
tables, and the vsini data were taken from the Gaia DR3 esphs tables. We
show that for nearby OBAF-type pulsators, the Gaia DR3 data are
precise and accurate enough to pinpoint them in the Hertzsprung-Russell
diagram. We find empirical instability strips covering broader regions
than theoretically predicted. In particular, our study reveals the
presence of fast rotating gravity-mode pulsators outside the strips,
as well as the co-existence of rotationally modulated variables inside
the strips as reported before in the literature. We derive an extensive
period-luminosity relation for delta Sct stars and provide evidence that
the relation features different regimes depending on the oscillation
period. Finally, we demonstrate how stellar rotation attenuates the
amplitude of the dominant oscillation mode of delta Sct stars.
Title: Gaia Data Release 3: Stellar multiplicity, a teaser for the
hidden treasure
Authors: Gaia Collaboration; Arenou, F.; Babusiaux, C.; Barstow,
M. A.; Faigler, S.; Jorissen, A.; Kervella, P.; Mazeh, T.; Mowlavi,
N.; Panuzzo, P.; Sahlmann, J.; Shahaf, S.; Sozzetti, A.; Bauchet, N.;
Damerdji, Y.; Gavras, P.; Giacobbe, P.; Gosset, E.; Halbwachs, J. -L.;
Holl, B.; Lattanzi, M. G.; Leclerc, N.; Morel, T.; Pourbaix, D.; Re
Fiorentin, P.; Sadowski, G.; Ségransan, D.; Siopis, C.; Teyssier, D.;
Zwitter, T.; Planquart, L.; Brown, A. G. A.; Vallenari, A.; Prusti,
T.; de Bruijne, J. H. J.; Biermann, M.; Creevey, O. L.; Ducourant, C.;
Evans, D. W.; Eyer, L.; Guerra, R.; Hutton, A.; Jordi, C.; Klioner,
S. A.; Lammers, U. L.; Lindegren, L.; Luri, X.; Mignard, F.; Panem,
C.; Randich, S.; Sartoretti, P.; Soubiran, C.; Tanga, P.; Walton,
N. A.; Bailer-Jones, C. A. L.; Bastian, U.; Drimmel, R.; Jansen, F.;
Katz, D.; van Leeuwen, F.; Bakker, J.; Cacciari, C.; Castañeda, J.;
De Angeli, F.; Fabricius, C.; Fouesneau, M.; Frémat, Y.; Galluccio,
L.; Guerrier, A.; Heiter, U.; Masana, E.; Messineo, R.; Nicolas,
C.; Nienartowicz, K.; Pailler, F.; Riclet, F.; Roux, W.; Seabroke,
G. M.; Sordo, R.; Thévenin, F.; Gracia-Abril, G.; Portell, J.;
Altmann, M.; Andrae, R.; Audard, M.; Bellas-Velidis, I.; Benson,
K.; Berthier, J.; Blomme, R.; Burgess, P. W.; Busonero, D.; Busso,
G.; Cánovas, H.; Carry, B.; Cellino, A.; Cheek, N.; Clementini,
G.; Davidson, M.; de Teodoro, P.; Nuñez Campos, M.; Delchambre,
L.; Dell'Oro, A.; Esquej, P.; Fernández-Hernández, J.; Fraile,
E.; Garabato, D.; García-Lario, P.; Haigron, R.; Hambly, N. C.;
Harrison, D. L.; Hernández, J.; Hestroffer, D.; Hodgkin, S. T.;
Janßen, K.; Jevardat de Fombelle, G.; Jordan, S.; Krone-Martins,
A.; Lanzafame, A. C.; Löffler, W.; Marchal, O.; Marrese, P. M.;
Moitinho, A.; Muinonen, K.; Osborne, P.; Pancino, E.; Pauwels, T.;
Recio-Blanco, A.; Reylé, C.; Riello, M.; Rimoldini, L.; Roegiers,
T.; Rybizki, J.; Sarro, L. M.; Smith, M.; Utrilla, E.; van Leeuwen,
M.; Abbas, U.; Ábrahám, P.; Abreu Aramburu, A.; Aerts, C.; Aguado,
J. J.; Ajaj, M.; Aldea-Montero, F.; Altavilla, G.; Álvarez, M. A.;
Alves, J.; Anders, F.; Anderson, R. I.; Anglada Varela, E.; Antoja, T.;
Baines, D.; Baker, S. G.; Balaguer-Núñez, L.; Balbinot, E.; Balog,
Z.; Barache, C.; Barbato, D.; Barros, M.; Bartolomé, S.; Bassilana,
J. -L.; Becciani, U.; Bellazzini, M.; Berihuete, A.; Bernet, M.;
Bertone, S.; Bianchi, L.; Binnenfeld, A.; Blanco-Cuaresma, S.; Blazere,
A.; Boch, T.; Bombrun, A.; Bossini, D.; Bouquillon, S.; Bragaglia, A.;
Bramante, L.; Breedt, E.; Bressan, A.; Brouillet, N.; Brugaletta, E.;
Bucciarelli, B.; Burlacu, A.; Butkevich, A. G.; Buzzi, R.; Caffau,
E.; Cancelliere, R.; Cantat-Gaudin, T.; Carballo, R.; Carlucci, T.;
Carnerero, M. I.; Carrasco, J. M.; Casamiquela, L.; Castellani, M.;
Castro-Ginard, A.; Chaoul, L.; Charlot, P.; Chemin, L.; Chiaramida,
V.; Chiavassa, A.; Chornay, N.; Comoretto, G.; Contursi, G.; Cooper,
W. J.; Cornez, T.; Cowell, S.; Crifo, F.; Cropper, M.; Crosta, M.;
Crowley, C.; Dafonte, C.; Dapergolas, A.; David, P.; de Laverny, P.;
De Luise, F.; De March, R.; De Ridder, J.; de Souza, R.; de Torres,
A.; del Peloso, E. F.; del Pozo, E.; Delbo, M.; Delgado, A.; Delisle,
J. -B.; Demouchy, C.; Dharmawardena, T. E.; Diakite, S.; Diener,
C.; Distefano, E.; Dolding, C.; Enke, H.; Fabre, C.; Fabrizio, M.;
Fedorets, G.; Fernique, P.; Figueras, F.; Fournier, Y.; Fouron, C.;
Fragkoudi, F.; Gai, M.; Garcia-Gutierrez, A.; Garcia-Reinaldos, M.;
García-Torres, M.; Garofalo, A.; Gavel, A.; Gerlach, E.; Geyer,
R.; Gilmore, G.; Girona, S.; Giuffrida, G.; Gomel, R.; Gomez, A.;
González-Núñez, J.; González-Santamaría, I.; González-Vidal,
J. J.; Granvik, M.; Guillout, P.; Guiraud, J.; Gutiérrez-Sánchez, R.;
Guy, L. P.; Hatzidimitriou, D.; Hauser, M.; Haywood, M.; Helmer, A.;
Helmi, A.; Sarmiento, M. H.; Hidalgo, S. L.; Hładczuk, N.; Hobbs, D.;
Holland, G.; Huckle, H. E.; Jardine, K.; Jasniewicz, G.; Jean-Antoine
Piccolo, A.; Jiménez-Arranz, Ó.; Juaristi Campillo, J.; Julbe, F.;
Karbevska, L.; Khanna, S.; Kordopatis, G.; Korn, A. J.; Kóspál,
Á; Kostrzewa-Rutkowska, Z.; Kruszyńska, K.; Kun, M.; Laizeau, P.;
Lambert, S.; Lanza, A. F.; Lasne, Y.; Le Campion, J. -F.; Lebreton, Y.;
Lebzelter, T.; Leccia, S.; Lecoeur-Taibi, I.; Liao, S.; Licata, E. L.;
Lindstrøm, H. E. P.; Lister, T. A.; Livanou, E.; Lobel, A.; Lorca,
A.; Loup, C.; Madrero Pardo, P.; Magdaleno Romeo, A.; Managau, S.;
Mann, R. G.; Manteiga, M.; Marchant, J. M.; Marconi, M.; Marcos, J.;
Marcos Santos, M. M. S.; Marín Pina, D.; Marinoni, S.; Marocco, F.;
Marshall, D. J.; Polo, L. Martin; Martín-Fleitas, J. M.; Marton, G.;
Mary, N.; Masip, A.; Massari, D.; Mastrobuono-Battisti, A.; McMillan,
P. J.; Messina, S.; Michalik, D.; Millar, N. R.; Mints, A.; Molina, D.;
Molinaro, R.; Molnár, L.; Monari, G.; Monguió, M.; Montegriffo, P.;
Montero, A.; Mor, R.; Mora, A.; Morbidelli, R.; Morris, D.; Muraveva,
T.; Murphy, C. P.; Musella, I.; Nagy, Z.; Noval, L.; Ocaña, F.; Ogden,
A.; Ordenovic, C.; Osinde, J. O.; Pagani, C.; Pagano, I.; Palaversa,
L.; Palicio, P. A.; Pallas-Quintela, L.; Panahi, A.; Payne-Wardenaar,
S.; Peñalosa Esteller, X.; Penttilä, A.; Pichon, B.; Piersimoni,
A. M.; Pineau, F. -X.; Plachy, E.; Plum, G.; Poggio, E.; Prša, A.;
Pulone, L.; Racero, E.; Ragaini, S.; Rainer, M.; Raiteri, C. M.; Ramos,
P.; Ramos-Lerate, M.; Regibo, S.; Richards, P. J.; Rios Diaz, C.;
Ripepi, V.; Riva, A.; Rix, H. -W.; Rixon, G.; Robichon, N.; Robin,
A. C.; Robin, C.; Roelens, M.; Rogues, H. R. O.; Rohrbasser, L.;
Romero-Gómez, M.; Rowell, N.; Royer, F.; Ruz Mieres, D.; Rybicki,
K. A.; Sáez Núñez, A.; Sagristà Sellés, A.; Salguero, E.; Samaras,
N.; Sanchez Gimenez, V.; Sanna, N.; Santoveña, R.; Sarasso, M.;
Schultheis, M. S.; Sciacca, E.; Segol, M.; Segovia, J. C.; Semeux,
D.; Siddiqui, H. I.; Siebert, A.; Siltala, L.; Silvelo, A.; Slezak,
E.; Slezak, I.; Smart, R. L.; Snaith, O. N.; Solano, E.; Solitro,
F.; Souami, D.; Souchay, J.; Spagna, A.; Spina, L.; Spoto, F.;
Steele, I. A.; Steidelmüller, H.; Stephenson, C. A.; Süveges,
M.; Surdej, J.; Szabados, L.; Szegedi-Elek, E.; Taris, F.; Taylor,
M. B.; Teixeira, R.; Tolomei, L.; Tonello, N.; Torra, F.; Torra, J.;
Torralba Elipe, G.; Trabucchi, M.; Tsounis, A. T.; Turon, C.; Ulla,
A.; Unger, N.; Vaillant, M. V.; van Dillen, E.; van Reeven, W.; Vanel,
O.; Vecchiato, A.; Viala, Y.; Vicente, D.; Voutsinas, S.; Weiler,
M.; Wevers, T.; Wyrzykowski, Ł.; Yoldas, A.; Yvard, P.; Zhao, H.;
Zorec, J.; Zucker, S.
Bibcode: 2022arXiv220605595G
Altcode:
The Gaia DR3 Catalogue contains for the first time about eight
hundred thousand solutions with either orbital elements or trend
parameters for astrometric, spectroscopic and eclipsing binaries, and
combinations of them. This paper aims to illustrate the huge potential
of this large non-single star catalogue. Using the orbital solutions
together with models of the binaries, a catalogue of tens of thousands
of stellar masses, or lower limits, partly together with consistent
flux ratios, has been built. Properties concerning the completeness
of the binary catalogues are discussed, statistical features of the
orbital elements are explained and a comparison with other catalogues
is performed. Illustrative applications are proposed for binaries
across the H-R diagram. The binarity is studied in the RGB/AGB and a
search for genuine SB1 among long-period variables is performed. The
discovery of new EL CVn systems illustrates the potential of combining
variability and binarity catalogues. Potential compact object companions
are presented, mainly white dwarf companions or double degenerates,
but one candidate neutron star is also presented. Towards the bottom of
the main sequence, the orbits of previously-suspected binary ultracool
dwarfs are determined and new candidate binaries are discovered. The
long awaited contribution of Gaia to the analysis of the substellar
regime shows the brown dwarf desert around solar-type stars using true,
rather than minimum, masses, and provides new important constraints on
the occurrence rates of substellar companions to M dwarfs. Several
dozen new exoplanets are proposed, including two with validated
orbital solutions and one super-Jupiter orbiting a white dwarf, all
being candidates requiring confirmation. Beside binarity, higher order
multiple systems are also found.
Title: Gaia Data Release 3: Chemical cartography of the Milky Way
Authors: Gaia Collaboration; Recio-Blanco, A.; Kordopatis, G.; de
Laverny, P.; Palicio, P. A.; Spagna, A.; Spina, L.; Katz, D.; Re
Fiorentin, P.; Poggio, E.; McMillan, P. J.; Vallenari, A.; Lattanzi,
M. G.; Seabroke, G. M.; Casamiquela, L.; Bragaglia, A.; Antoja,
T.; Bailer-Jones, C. A. L.; Andrae, R.; Fouesneau, M.; Cropper, M.;
Cantat-Gaudin, T.; Heiter, U.; Bijaoui, A.; Brown, A. G. A.; Prusti,
T.; de Bruijne, J. H. J.; Arenou, F.; Babusiaux, C.; Biermann, M.;
Creevey, O. L.; Ducourant, C.; Evans, D. W.; Eyer, L.; Guerra, R.;
Hutton, A.; Jordi, C.; Klioner, S. A.; Lammers, U. L.; Lindegren,
L.; Luri, X.; Mignard, F.; Panem, C.; Pourbaix, D.; Randich, S.;
Sartoretti, P.; Soubiran, C.; Tanga, P.; Walton, N. A.; Bastian, U.;
Drimmel, R.; Jansen, F.; van Leeuwen, F.; Bakker, J.; Cacciari, C.;
Castañeda, J.; De Angeli, F.; Fabricius, C.; Frémat, Y.; Galluccio,
L.; Guerrier, A.; Masana, E.; Messineo, R.; Mowlavi, N.; Nicolas,
C.; Nienartowicz, K.; Pailler, F.; Panuzzo, P.; Riclet, F.; Roux, W.;
Sordo, R.; Thévenin, F.; Gracia-Abril, G.; Portell, J.; Teyssier, D.;
Altmann, M.; Audard, M.; Bellas-Velidis, I.; Benson, K.; Berthier,
J.; Blomme, R.; Burgess, P. W.; Busonero, D.; Busso, G.; Cánovas,
H.; Carry, B.; Cellino, A.; Cheek, N.; Clementini, G.; Damerdji,
Y.; Davidson, M.; de Teodoro, P.; Nuñez Campos, M.; Delchambre,
L.; Dell'Oro, A.; Esquej, P.; Fernández-Hernández, J.; Fraile, E.;
Garabato, D.; García-Lario, P.; Gosset, E.; Haigron, R.; Halbwachs,
J. -L.; Hambly, N. C.; Harrison, D. L.; Hernández, J.; Hestroffer,
D.; Hodgkin, S. T.; Holl, B.; Janßen, K.; Jevardat de Fombelle, G.;
Jordan, S.; Krone-Martins, A.; Lanzafame, A. C.; Löffler, W.; Marchal,
O.; Marrese, P. M.; Moitinho, A.; Muinonen, K.; Osborne, P.; Pancino,
E.; Pauwels, T.; Reylé, C.; Riello, M.; Rimoldini, L.; Roegiers,
T.; Rybizki, J.; Sarro, L. M.; Siopis, C.; Smith, M.; Sozzetti,
A.; Utrilla, E.; van Leeuwen, M.; Abbas, U.; Ábrahám, P.; Abreu
Aramburu, A.; Aerts, C.; Aguado, J. J.; Ajaj, M.; Aldea-Montero, F.;
Altavilla, G.; Álvarez, M. A.; Alves, J.; Anders, F.; Anderson, R. I.;
Anglada Varela, E.; Baines, D.; Baker, S. G.; Balaguer-Núñez, L.;
Balbinot, E.; Balog, Z.; Barache, C.; Barbato, D.; Barros, M.; Barstow,
M. A.; Bartolomé, S.; Bassilana, J. -L.; Bauchet, N.; Becciani, U.;
Bellazzini, M.; Berihuete, A.; Bernet, M.; Bertone, S.; Bianchi, L.;
Binnenfeld, A.; Blanco-Cuaresma, S.; Boch, T.; Bombrun, A.; Bossini,
D.; Bouquillon, S.; Bramante, L.; Breedt, E.; Bressan, A.; Brouillet,
N.; Brugaletta, E.; Bucciarelli, B.; Burlacu, A.; Butkevich, A. G.;
Buzzi, R.; Caffau, E.; Cancelliere, R.; Carballo, R.; Carlucci, T.;
Carnerero, M. I.; Carrasco, J. M.; Castellani, M.; Castro-Ginard,
A.; Chaoul, L.; Charlot, P.; Chemin, L.; Chiaramida, V.; Chiavassa,
A.; Chornay, N.; Comoretto, G.; Contursi, G.; Cooper, W. J.; Cornez,
T.; Cowell, S.; Crifo, F.; Crosta, M.; Crowley, C.; Dafonte, C.;
Dapergolas, A.; David, P.; De Luise, F.; De March, R.; De Ridder,
J.; de Souza, R.; de Torres, A.; del Peloso, E. F.; del Pozo, E.;
Delbo, M.; Delgado, A.; Delisle, J. -B.; Demouchy, C.; Dharmawardena,
T. E.; Di Matteo, P.; Diakite, S.; Diener, C.; Distefano, E.; Dolding,
C.; Edvardsson, B.; Enke, H.; Fabre, C.; Fabrizio, M.; Faigler, S.;
Fedorets, G.; Fernique, P.; Figueras, F.; Fournier, Y.; Fouron, C.;
Fragkoudi, F.; Gai, M.; Garcia-Gutierrez, A.; Garcia-Reinaldos, M.;
García-Torres, M.; Garofalo, A.; Gavel, A.; Gavras, P.; Gerlach,
E.; Geyer, R.; Giacobbe, P.; Gilmore, G.; Girona, S.; Giuffrida, G.;
Gomel, R.; Gomez, A.; González-Núñez, J.; González-Santamaría,
I.; González-Vidal, J. J.; Granvik, M.; Guillout, P.; Guiraud, J.;
Gutiérrez-Sánchez, R.; Guy, L. P.; Hatzidimitriou, D.; Hauser,
M.; Haywood, M.; Helmer, A.; Helmi, A.; Sarmiento, M. H.; Hidalgo,
S. L.; Hładczuk, N.; Hobbs, D.; Holland, G.; Huckle, H. E.; Jardine,
K.; Jasniewicz, G.; Jean-Antoine Piccolo, A.; Jiménez-Arranz,
Ó.; Juaristi Campillo, J.; Julbe, F.; Karbevska, L.; Kervella,
P.; Khanna, S.; Korn, A. J.; Kóspál, Á; Kostrzewa-Rutkowska,
Z.; Kruszyńska, K.; Kun, M.; Laizeau, P.; Lambert, S.; Lanza,
A. F.; Lasne, Y.; Le Campion, J. -F.; Lebreton, Y.; Lebzelter, T.;
Leccia, S.; Leclerc, N.; Lecoeur-Taibi, I.; Liao, S.; Licata, E. L.;
Lindstrøm, H. E. P.; Lister, T. A.; Livanou, E.; Lobel, A.; Lorca,
A.; Loup, C.; Madrero Pardo, P.; Magdaleno Romeo, A.; Managau, S.;
Mann, R. G.; Manteiga, M.; Marchant, J. M.; Marconi, M.; Marcos, J.;
Marcos Santos, M. M. S.; Marín Pina, D.; Marinoni, S.; Marocco, F.;
Marshall, D. J.; Polo, L. Martin; Martín-Fleitas, J. M.; Marton, G.;
Mary, N.; Masip, A.; Massari, D.; Mastrobuono-Battisti, A.; Mazeh,
T.; Messina, S.; Michalik, D.; Millar, N. R.; Mints, A.; Molina, D.;
Molinaro, R.; Molnár, L.; Monari, G.; Monguió, M.; Montegriffo, P.;
Montero, A.; Mor, R.; Mora, A.; Morbidelli, R.; Morel, T.; Morris, D.;
Muraveva, T.; Murphy, C. P.; Musella, I.; Nagy, Z.; Noval, L.; Ocaña,
F.; Ogden, A.; Ordenovic, C.; Osinde, J. O.; Pagani, C.; Pagano, I.;
Palaversa, L.; Pallas-Quintela, L.; Panahi, A.; Payne-Wardenaar, S.;
Peñalosa Esteller, X.; Penttilä, A.; Pichon, B.; Piersimoni, A. M.;
Pineau, F. -X.; Plachy, E.; Plum, G.; Prša, A.; Pulone, L.; Racero,
E.; Ragaini, S.; Rainer, M.; Raiteri, C. M.; Ramos, P.; Ramos-Lerate,
M.; Regibo, S.; Richards, P. J.; Rios Diaz, C.; Ripepi, V.; Riva,
A.; Rix, H. -W.; Rixon, G.; Robichon, N.; Robin, A. C.; Robin, C.;
Roelens, M.; Rogues, H. R. O.; Rohrbasser, L.; Romero-Gómez, M.;
Rowell, N.; Royer, F.; Ruz Mieres, D.; Rybicki, K. A.; Sadowski, G.;
Sáez Núñez, A.; Sagristà Sellés, A.; Sahlmann, J.; Salguero,
E.; Samaras, N.; Sanchez Gimenez, V.; Sanna, N.; Santoveña, R.;
Sarasso, M.; Schultheis, M.; Sciacca, E.; Segol, M.; Segovia, J. C.;
Ségransan, D.; Semeux, D.; Shahaf, S.; Siddiqui, H. I.; Siebert,
A.; Siltala, L.; Silvelo, A.; Slezak, E.; Slezak, I.; Smart, R. L.;
Snaith, O. N.; Solano, E.; Solitro, F.; Souami, D.; Souchay, J.;
Spoto, F.; Steele, I. A.; Steidelmüller, H.; Stephenson, C. A.;
Süveges, M.; Surdej, J.; Szabados, L.; Szegedi-Elek, E.; Taris,
F.; Taylor, M. B.; Teixeira, R.; Tolomei, L.; Tonello, N.; Torra,
F.; Torra, J.; Torralba Elipe, G.; Trabucchi, M.; Tsounis, A. T.;
Turon, C.; Ulla, A.; Unger, N.; Vaillant, M. V.; van Dillen, E.;
van Reeven, W.; Vanel, O.; Vecchiato, A.; Viala, Y.; Vicente, D.;
Voutsinas, S.; Weiler, M.; Wevers, T.; Wyrzykowski, Ł.; Yoldas, A.;
Yvard, P.; Zhao, H.; Zorec, J.; Zucker, S.; Zwitter, T.
Bibcode: 2022arXiv220605534G
Altcode:
Gaia DR3 opens a new era of all-sky spectral analysis of stellar
populations thanks to the nearly 5.6 million stars observed by the RVS
and parametrised by the GSP-spec module. The all-sky Gaia chemical
cartography allows a powerful and precise chemo-dynamical view of
the Milky Way with unprecedented spatial coverage and statistical
robustness. First, it reveals the strong vertical symmetry of the
Galaxy and the flared structure of the disc. Second, the observed
kinematic disturbances of the disc -- seen as phase space correlations
-- and kinematic or orbital substructures are associated with chemical
patterns that favour stars with enhanced metallicities and lower
[alpha/Fe] abundance ratios compared to the median values in the radial
distributions. This is detected both for young objects that trace the
spiral arms and older populations. Several alpha, iron-peak elements
and at least one heavy element trace the thin and thick disc properties
in the solar cylinder. Third, young disc stars show a recent chemical
impoverishment in several elements. Fourth, the largest chemo-dynamical
sample of open clusters analysed so far shows a steepening of the
radial metallicity gradient with age, which is also observed in the
young field population. Finally, the Gaia chemical data have the
required coverage and precision to unveil galaxy accretion debris
and heated disc stars on halo orbits through their [alpha/Fe] ratio,
and to allow the study of the chemo-dynamical properties of globular
clusters. Gaia DR3 chemo-dynamical diagnostics open new horizons before
the era of ground-based wide-field spectroscopic surveys. They unveil
a complex Milky Way that is the outcome of an eventful evolution,
shaping it to the present day (abridged).
Title: Gaia Early Data Release 3: The celestial reference frame
(Gaia-CRF3)
Authors: Gaia Collaboration; Klioner, S. A.; Lindegren, L.; Mignard,
F.; Hernández, J.; Ramos-Lerate, M.; Bastian, U.; Biermann, M.;
Bombrun, A.; de Torres, A.; Gerlach, E.; Geyer, R.; Hilger, T.; Hobbs,
D.; Lammers, U. L.; McMillan, P. J.; Steidelmüller, H.; Teyssier, D.;
Raiteri, C. M.; Bartolomé, S.; Bernet, M.; Castañeda, J.; Clotet,
M.; Davidson, M.; Fabricius, C.; Garralda Torres, N.; González-Vidal,
J. J.; Portell, J.; Rowell, N.; Torra, F.; Torra, J.; Brown, A. G. A.;
Vallenari, A.; Prusti, T.; de Bruijne, J. H. J.; Arenou, F.; Babusiaux,
C.; Creevey, O. L.; Ducourant, C.; Evans, D. W.; Eyer, L.; Guerra, R.;
Hutton, A.; Jordi, C.; Luri, X.; Panem, C.; Pourbaix, D.; Randich, S.;
Sartoretti, P.; Soubiran, C.; Tanga, P.; Walton, N. A.; Bailer-Jones,
C. A. L.; Drimmel, R.; Jansen, F.; Katz, D.; Lattanzi, M. G.; van
Leeuwen, F.; Bakker, J.; Cacciari, C.; De Angeli, F.; Fouesneau, M.;
Frémat, Y.; Galluccio, L.; Guerrier, A.; Heiter, U.; Masana, E.;
Messineo, R.; Mowlavi, N.; Nicolas, C.; Nienartowicz, K.; Pailler,
F.; Panuzzo, P.; Riclet, F.; Roux, W.; Seabroke, G. M.; Sordo, R.;
Thévenin, F.; Gracia-Abril, G.; Altmann, M.; Andrae, R.; Audard, M.;
Bellas-Velidis, I.; Benson, K.; Berthier, J.; Blomme, R.; Burgess,
P. W.; Busonero, D.; Busso, G.; Cánovas, H.; Carry, B.; Cellino, A.;
Cheek, N.; Clementini, G.; Damerdji, Y.; de Teodoro, P.; Nuñez Campos,
M.; Delchambre, L.; Dell'Oro, A.; Esquej, P.; Fernández-Hernández,
J.; Fraile, E.; Garabato, D.; García-Lario, P.; Gosset, E.; Haigron,
R.; Halbwachs, J. -L.; Hambly, N. C.; Harrison, D. L.; Hestroffer,
D.; Hodgkin, S. T.; Holl, B.; Janßen, K.; Jevardat de Fombelle,
G.; Jordan, S.; Krone-Martins, A.; Lanzafame, A. C.; Löffler, W.;
Marchal, O.; Marrese, P. M.; Moitinho, A.; Muinonen, K.; Osborne,
P.; Pancino, E.; Pauwels, T.; Recio-Blanco, A.; Reylé, C.; Riello,
M.; Rimoldini, L.; Roegiers, T.; Rybizki, J.; Sarro, L. M.; Siopis,
C.; Smith, M.; Sozzetti, A.; Utrilla, E.; van Leeuwen, M.; Abbas, U.;
Ábrahám, P.; Abreu Aramburu, A.; Aerts, C.; Aguado, J. J.; Ajaj, M.;
Aldea-Montero, F.; Altavilla, G.; Álvarez, M. A.; Alves, J.; Anderson,
R. I.; Anglada Varela, E.; Antoja, T.; Baines, D.; Baker, S. G.;
Balaguer-Núñez, L.; Balbinot, E.; Balog, Z.; Barache, C.; Barbato,
D.; Barros, M.; Barstow, M. A.; Bassilana, J. -L.; Bauchet, N.;
Becciani, U.; Bellazzini, M.; Berihuete, A.; Bertone, S.; Bianchi, L.;
Binnenfeld, A.; Blanco-Cuaresma, S.; Boch, T.; Bossini, D.; Bouquillon,
S.; Bragaglia, A.; Bramante, L.; Breedt, E.; Bressan, A.; Brouillet,
N.; Brugaletta, E.; Bucciarelli, B.; Burlacu, A.; Butkevich, A. G.;
Buzzi, R.; Caffau, E.; Cancelliere, R.; Cantat-Gaudin, T.; Carballo,
R.; Carlucci, T.; Carnerero, M. I.; Carrasco, J. M.; Casamiquela,
L.; Castellani, M.; Castro-Ginard, A.; Chaoul, L.; Charlot, P.;
Chemin, L.; Chiaramida, V.; Chiavassa, A.; Chornay, N.; Comoretto,
G.; Contursi, G.; Cooper, W. J.; Cornez, T.; Cowell, S.; Crifo, F.;
Cropper, M.; Crosta, M.; Crowley, C.; Dafonte, C.; Dapergolas, A.;
David, P.; de Laverny, P.; De Luise, F.; De March, R.; De Ridder, J.;
de Souza, R.; del Peloso, E. F.; del Pozo, E.; Delbo, M.; Delgado,
A.; Delisle, J. -B.; Demouchy, C.; Dharmawardena, T. E.; Diakite, S.;
Diener, C.; Distefano, E.; Dolding, C.; Enke, H.; Fabre, C.; Fabrizio,
M.; Faigler, S.; Fedorets, G.; Fernique, P.; Fienga, A.; Figueras, F.;
Fournier, Y.; Fouron, C.; Fragkoudi, F.; Gai, M.; Garcia-Gutierrez,
A.; Garcia-Reinaldos, M.; García-Torres, M.; Garofalo, A.; Gavel,
A.; Gavras, P.; Giacobbe, P.; Gilmore, G.; Girona, S.; Giuffrida, G.;
Gomel, R.; Gomez, A.; González-Núñez, J.; González-Santamaría,
I.; Granvik, M.; Guillout, P.; Guiraud, J.; Gutiérrez-Sánchez, R.;
Guy, L. P.; Hatzidimitriou, D.; Hauser, M.; Haywood, M.; Helmer, A.;
Helmi, A.; Sarmiento, M. H.; Hidalgo, S. L.; Hładczuk, N.; Holland,
G.; Huckle, H. E.; Jardine, K.; Jasniewicz, G.; Jean-Antoine Piccolo,
A.; Jiménez-Arranz, Ó.; Juaristi Campillo, J.; Julbe, F.; Karbevska,
L.; Kervella, P.; Khanna, S.; Kordopatis, G.; Korn, A. J.; Kóspál,
Á; Kostrzewa-Rutkowska, Z.; Kruszyńska, K.; Kun, M.; Laizeau, P.;
Lambert, S.; Lanza, A. F.; Lasne, Y.; Le Campion, J. -F.; Lebreton,
Y.; Lebzelter, T.; Leccia, S.; Leclerc, N.; Lecoeur-Taibi, I.; Liao,
S.; Licata, E. L.; Lindstrøm, H. E. P.; Lister, T. A.; Livanou, E.;
Lobel, A.; Lorca, A.; Loup, C.; Madrero Pardo, P.; Magdaleno Romeo,
A.; Managau, S.; Mann, R. G.; Manteiga, M.; Marchant, J. M.; Marconi,
M.; Marcos, J.; Marcos Santos, M. M. S.; Marín Pina, D.; Marinoni, S.;
Marocco, F.; Marshall, D. J.; Polo, L. Martin; Martín-Fleitas, J. M.;
Marton, G.; Mary, N.; Masip, A.; Massari, D.; Mastrobuono-Battisti, A.;
Mazeh, T.; Messina, S.; Michalik, D.; Millar, N. R.; Mints, A.; Molina,
D.; Molinaro, R.; Molnár, L.; Monari, G.; Monguió, M.; Montegriffo,
P.; Montero, A.; Mor, R.; Mora, A.; Morbidelli, R.; Morel, T.; Morris,
D.; Muraveva, T.; Murphy, C. P.; Musella, I.; Nagy, Z.; Noval, L.;
Ocaña, F.; Ogden, A.; Ordenovic, C.; Osinde, J. O.; Pagani, C.;
Pagano, I.; Palaversa, L.; Palicio, P. A.; Pallas-Quintela, L.;
Panahi, A.; Payne-Wardenaar, S.; Peñalosa Esteller, X.; Penttilä,
A.; Pichon, B.; Piersimoni, A. M.; Pineau, F. -X.; Plachy, E.; Plum,
G.; Poggio, E.; Prša, A.; Pulone, L.; Racero, E.; Ragaini, S.;
Rainer, M.; Rambaux, N.; Ramos, P.; Re Fiorentin, P.; Regibo, S.;
Richards, P. J.; Rios Diaz, C.; Ripepi, V.; Riva, A.; Rix, H. -W.;
Rixon, G.; Robichon, N.; Robin, A. C.; Robin, C.; Roelens, M.; Rogues,
H. R. O.; Rohrbasser, L.; Romero-Gómez, M.; Royer, F.; Ruz Mieres, D.;
Rybicki, K. A.; Sadowski, G.; Sáez Núñez, A.; Sagristà Sellés, A.;
Sahlmann, J.; Salguero, E.; Samaras, N.; Sanchez Gimenez, V.; Sanna,
N.; Santoveña, R.; Sarasso, M.; Schultheis, M.; Sciacca, E.; Segol,
M.; Segovia, J. C.; Ségransan, D.; Semeux, D.; Shahaf, S.; Siddiqui,
H. I.; Siebert, A.; Siltala, L.; Silvelo, A.; Slezak, E.; Slezak,
I.; Smart, R. L.; Snaith, O. N.; Solano, E.; Solitro, F.; Souami,
D.; Souchay, J.; Spagna, A.; Spina, L.; Spoto, F.; Steele,
I. A.; Stephenson, C. A.; Süveges, M.; Surdej, J.; Szabados, L.;
Szegedi-Elek, E.; Taris, F.; Taylor, M. B.; Teixeira, R.; Tolomei,
L.; Tonello, N.; Torralba Elipe, G.; Trabucchi, M.; Tsounis, A. T.;
Turon, C.; Ulla, A.; Unger, N.; Vaillant, M. V.; van Dillen, E.;
van Reeven, W.; Vanel, O.; Vecchiato, A.; Viala, Y.; Vicente, D.;
Voutsinas, S.; Weiler, M.; Wevers, T.; Wyrzykowski, Ł.; Yoldas, A.;
Yvard, P.; Zhao, H.; Zorec, J.; Zucker, S.; Zwitter, T.
Bibcode: 2022arXiv220412574G
Altcode:
Gaia-CRF3 is the celestial reference frame for positions and proper
motions in the third release of data from the Gaia mission, Gaia DR3
(and for the early third release, Gaia EDR3, which contains identical
astrometric results). The reference frame is defined by the positions
and proper motions at epoch 2016.0 for a specific set of extragalactic
sources in the (E)DR3 catalogue. We describe the construction of
Gaia-CRF3, and its properties in terms of the distributions in
magnitude, colour, and astrometric quality. Compact extragalactic
sources in Gaia DR3 were identified by positional cross-matching with
17 external catalogues of quasars (QSO) and active galactic nuclei
(AGN), followed by astrometric filtering designed to remove stellar
contaminants. Selecting a clean sample was favoured over including a
higher number of extragalactic sources. For the final sample, the random
and systematic errors in the proper motions are analysed, as well as the
radio-optical offsets in position for sources in the third realisation
of the International Celestial Reference Frame (ICRF3). The Gaia-CRF3
comprises about 1.6 million QSO-like sources, of which 1.2 million have
five-parameter astrometric solutions in Gaia DR3 and 0.4 million have
six-parameter solutions. The sources span the magnitude range G = 13
to 21 with a peak density at 20.6 mag, at which the typical positional
uncertainty is about 1 mas. The proper motions show systematic errors
on the level of 12 ${\mu}$as yr${}^{-1}$ on angular scales greater than
15 deg. For the 3142 optical counterparts of ICRF3 sources in the S/X
frequency bands, the median offset from the radio positions is about
0.5 mas, but exceeds 4 mas in either coordinate for 127 sources. We
outline the future of the Gaia-CRF in the next Gaia data releases.
Title: The Fingerprints of Volcanism: Modelling Secondary Atmospheres
on Rocky Planets
Authors: Liggins, P.; Jordan, S.; Rimmer, P. B.; Shorttle, O.
Bibcode: 2022LPICo2678.1933L
Altcode:
Volcanic atmospheres of rocky planets with Venus-like surface
temperatures can be classified according to their composition, and
linked back to the mantle fO2.
Title: A catalogue of white dwarfs in Gaia EDR3
Authors: Gentile Fusillo, N. P.; Tremblay, P. -E.; Cukanovaite, E.;
Vorontseva, A.; Lallement, R.; Hollands, M.; Gänsicke, B. T.; Burdge,
K. B.; McCleery, J.; Jordan, S.
Bibcode: 2021MNRAS.508.3877G
Altcode: 2021MNRAS.tmp.2458F; 2021arXiv210607669G
We present a catalogue of white dwarf candidates selected from Gaia
Early Data Release 3 (EDR3). We applied several selection criteria in
absolute magnitude, colour, and Gaia quality flags to remove objects
with unreliable measurements while preserving most stars compatible
with the white dwarf locus in the Hertzsprung-Russell diagram. We then
used a sample of over 30 000 spectroscopically confirmed white dwarfs
and contaminants from the Sloan Digital Sky Survey (SDSS) to map the
distribution of these objects in the Gaia absolute magnitude-colour
space. Finally, we adopt the same method presented in our previous
work on Gaia Data Release 2 (DR2) to calculate a probability of being
a white dwarf (PWD) for ≃1.3 million sources that passed
our quality selection. The PWD values can be used to select a
sample of ${\simeq} 359\,000$ high-confidence white dwarf candidates. We
calculated stellar parameters (effective temperature, surface gravity,
and mass) for all these stars by fitting Gaia astrometry and photometry
with synthetic pure-H, pure-He, and mixed H-He atmospheric models. We
estimate an upper limit of 93 per cent for the overall completeness
of our catalogue for white dwarfs with G ≤ 20 mag and effective
temperature (Teff) > 7000 K, at high Galactic latitudes
(|b| > 20°). Alongside the main catalogue we include a reduced
proper motion extension containing ${\simeq} 10\,200$ white dwarf
candidates with unreliable parallax measurements that could, however,
be identified on the basis of their proper motion. We also performed
a cross-match of our catalogues with SDSS Data Release 16 (DR16)
spectroscopy and provide spectral classification based on visual
inspection for all resulting matches.
Title: Metabolic Signatures of an Aerial Biosphere in the Clouds of
Venus: A Self-Consistent Photo-Bio-Chemical Model
Authors: Jordan, S.; Rimmer, P. B.; Shorttle, O.
Bibcode: 2021LPICo2629.4056J
Altcode:
It is useful to investigate whether a hypothetical biosphere in the
clouds of Venus produces chemical changes in the atmosphere that are
observable and diagnostic. We present the first self consistent coupling
of metabolic pathways to a full-atmosphere (0 - 115 km) model of Venus,
utilizing plausible sulfur-based metabolisms found in the literature.
Title: VizieR Online Data Catalog: Catalogue of white dwarfs in Gaia
EDR3 (Gentile+, 2021)
Authors: Gentile Fusillo, N. P.; Tremblay, P. -E.; Cukanovaite, E.;
Vorontseva, A.; Lallement, R.; Hollands, M.; Gansicke, B. T.; Burdge,
K. B.; McCleery, J.; Jordan, S.
Bibcode: 2021yCat..75083877G
Altcode:
The main catalogue provides 1280266 stars selected from Gaia EDR3
with calculated probabilities of being a white dwarf (PWD). The
PWD values can used to reliably select high-confidence white dwarf
candidates with a flexible compromise between completeness and level
of potential contamination. As a generic guideline selecting objects
with PWD>0.75 recovers ~=359000 high -confidence white
dwarf candidates, 25632 of which have SDSS spectroscopy. ~=91 per
cent of these spectroscopic sources are confirmed white dwarfs, ~=1
per cent are contaminant objects, ~=3 per cent are white dwarf-main
sequence binaries or cataclysmic variables, and the rest have unreliable
classification. We also provide a Reduced Proper Motion (RPM) extension
to the main catalogue which contains Gaia white dwarf candidates with
unreliable paralax measurement, but that could be selected on the basis
of their proper motion. This catalogue extension also makes use of a
flexible probability parameter (PHwd) and we suggest to use
PHwd>0.85 to select a reliable set of high-confidence
white dwarf candidates. All Gaia sources in both catalogues have also
been cross matched with SDSS DR14 taking into account the difference in
epoch of observation and proper motions. Whether available we include
SDSS ugriz photometry. In a separate table we provide informations
on all the available SDSS spectra for the Gaia sources in the main
catalogue. (3 data files).
Title: Gaia Early Data Release 3. Summary of the contents and survey
properties (Corrigendum)
Authors: Gaia Collaboration; Brown, A. G. A.; Vallenari, A.;
Prusti, T.; de Bruijne, J. H. J.; Babusiaux, C.; Biermann, M.;
Creevey, O. L.; Evans, D. W.; Eyer, L.; Hutton, A.; Jansen, F.;
Jordi, C.; Klioner, S. A.; Lammers, U.; Lindegren, L.; Luri, X.;
Mignard, F.; Panem, C.; Pourbaix, D.; Randich, S.; Sartoretti, P.;
Soubiran, C.; Walton, N. A.; Arenou, F.; Bailer-Jones, C. A. L.;
Bastian, U.; Cropper, M.; Drimmel, R.; Katz, D.; Lattanzi, M. G.;
van Leeuwen, F.; Bakker, J.; Cacciari, C.; Castañeda, J.; De Angeli,
F.; Ducourant, C.; Fabricius, C.; Fouesneau, M.; Frémat, Y.; Guerra,
R.; Guerrier, A.; Guiraud, J.; Jean-Antoine Piccolo, A.; Masana, E.;
Messineo, R.; Mowlavi, N.; Nicolas, C.; Nienartowicz, K.; Pailler,
F.; Panuzzo, P.; Riclet, F.; Roux, W.; Seabroke, G. M.; Sordo, R.;
Tanga, P.; Thévenin, F.; Gracia-Abril, G.; Portell, J.; Teyssier,
D.; Altmann, M.; Andrae, R.; Bellas-Velidis, I.; Benson, K.; Berthier,
J.; Blomme, R.; Brugaletta, E.; Burgess, P. W.; Busso, G.; Carry, B.;
Cellino, A.; Cheek, N.; Clementini, G.; Damerdji, Y.; Davidson, M.;
Delchambre, L.; Dell'Oro, A.; Fernández-Hernández, J.; Galluccio,
L.; García-Lario, P.; Garcia-Reinaldos, M.; González-Núñez, J.;
Gosset, E.; Haigron, R.; Halbwachs, J. -L.; Hambly, N. C.; Harrison,
D. L.; Hatzidimitriou, D.; Heiter, U.; Hernández, J.; Hestroffer,
D.; Hodgkin, S. T.; Holl, B.; Janßen, K.; Jevardat de Fombelle, G.;
Jordan, S.; Krone-Martins, A.; Lanzafame, A. C.; Löffler, W.; Lorca,
A.; Manteiga, M.; Marchal, O.; Marrese, P. M.; Moitinho, A.; Mora, A.;
Muinonen, K.; Osborne, P.; Pancino, E.; Pauwels, T.; Petit, J. -M.;
Recio-Blanco, A.; Richards, P. J.; Riello, M.; Rimoldini, L.; Robin,
A. C.; Roegiers, T.; Rybizki, J.; Sarro, L. M.; Siopis, C.; Smith, M.;
Sozzetti, A.; Ulla, A.; Utrilla, E.; van Leeuwen, M.; van Reeven, W.;
Abbas, U.; Abreu Aramburu, A.; Accart, S.; Aerts, C.; Aguado, J. J.;
Ajaj, M.; Altavilla, G.; Álvarez, M. A.; Álvarez Cid-Fuentes, J.;
Alves, J.; Anderson, R. I.; Anglada Varela, E.; Antoja, T.; Audard, M.;
Baines, D.; Baker, S. G.; Balaguer-Núñez, L.; Balbinot, E.; Balog,
Z.; Barache, C.; Barbato, D.; Barros, M.; Barstow, M. A.; Bartolomé,
S.; Bassilana, J. -L.; Bauchet, N.; Baudesson-Stella, A.; Becciani, U.;
Bellazzini, M.; Bernet, M.; Bertone, S.; Bianchi, L.; Blanco-Cuaresma,
S.; Boch, T.; Bombrun, A.; Bossini, D.; Bouquillon, S.; Bragaglia, A.;
Bramante, L.; Breedt, E.; Bressan, A.; Brouillet, N.; Bucciarelli,
B.; Burlacu, A.; Busonero, D.; Butkevich, A. G.; Buzzi, R.; Caffau,
E.; Cancelliere, R.; Cánovas, H.; Cantat-Gaudin, T.; Carballo, R.;
Carlucci, T.; Carnerero, M. I.; Carrasco, J. M.; Casamiquela, L.;
Castellani, M.; Castro-Ginard, A.; Castro Sampol, P.; Chaoul, L.;
Charlot, P.; Chemin, L.; Chiavassa, A.; Cioni, M. -R. L.; Comoretto,
G.; Cooper, W. J.; Cornez, T.; Cowell, S.; Crifo, F.; Crosta, M.;
Crowley, C.; Dafonte, C.; Dapergolas, A.; David, M.; David, P.; de
Laverny, P.; De Luise, F.; De March, R.; De Ridder, J.; de Souza,
R.; de Teodoro, P.; de Torres, A.; del Peloso, E. F.; del Pozo, E.;
Delbo, M.; Delgado, A.; Delgado, H. E.; Delisle, J. -B.; Di Matteo,
P.; Diakite, S.; Diener, C.; Distefano, E.; Dolding, C.; Eappachen,
D.; Edvardsson, B.; Enke, H.; Esquej, P.; Fabre, C.; Fabrizio, M.;
Faigler, S.; Fedorets, G.; Fernique, P.; Fienga, A.; Figueras, F.;
Fouron, C.; Fragkoudi, F.; Fraile, E.; Franke, F.; Gai, M.; Garabato,
D.; Garcia-Gutierrez, A.; García-Torres, M.; Garofalo, A.; Gavras,
P.; Gerlach, E.; Geyer, R.; Giacobbe, P.; Gilmore, G.; Girona,
S.; Giuffrida, G.; Gomel, R.; Gomez, A.; Gonzalez-Santamaria, I.;
González-Vidal, J. J.; Granvik, M.; Gutiérrez-Sánchez, R.; Guy,
L. P.; Hauser, M.; Haywood, M.; Helmi, A.; Hidalgo, S. L.; Hilger,
T.; Hładczuk, N.; Hobbs, D.; Holland, G.; Huckle, H. E.; Jasniewicz,
G.; Jonker, P. G.; Juaristi Campillo, J.; Julbe, F.; Karbevska, L.;
Kervella, P.; Khanna, S.; Kochoska, A.; Kontizas, M.; Kordopatis, G.;
Korn, A. J.; Kostrzewa-Rutkowska, Z.; Kruszyńska, K.; Lambert, S.;
Lanza, A. F.; Lasne, Y.; Le Campion, J. -F.; Le Fustec, Y.; Lebreton,
Y.; Lebzelter, T.; Leccia, S.; Leclerc, N.; Lecoeur-Taibi, I.; Liao,
S.; Licata, E.; Lindstrøm, H. E. P.; Lister, T. A.; Livanou, E.;
Lobel, A.; Madrero Pardo, P.; Managau, S.; Mann, R. G.; Marchant,
J. M.; Marconi, M.; Marcos Santos, M. M. S.; Marinoni, S.; Marocco, F.;
Marshall, D. J.; Martin Polo, L.; Martín-Fleitas, J. M.; Masip, A.;
Massari, D.; Mastrobuono-Battisti, A.; Mazeh, T.; McMillan, P. J.;
Messina, S.; Michalik, D.; Millar, N. R.; Mints, A.; Molina, D.;
Molinaro, R.; Molnár, L.; Montegriffo, P.; Mor, R.; Morbidelli, R.;
Morel, T.; Morris, D.; Mulone, A. F.; Munoz, D.; Muraveva, T.; Murphy,
C. P.; Musella, I.; Noval, L.; Ordénovic, C.; Orrù, G.; Osinde,
J.; Pagani, C.; Pagano, I.; Palaversa, L.; Palicio, P. A.; Panahi,
A.; Pawlak, M.; Peñalosa Esteller, X.; Penttilä, A.; Piersimoni,
A. M.; Pineau, F. -X.; Plachy, E.; Plum, G.; Poggio, E.; Poretti,
E.; Poujoulet, E.; Prša, A.; Pulone, L.; Racero, E.; Ragaini, S.;
Rainer, M.; Raiteri, C. M.; Rambaux, N.; Ramos, P.; Ramos-Lerate,
M.; Re Fiorentin, P.; Regibo, S.; Reylé, C.; Ripepi, V.; Riva, A.;
Rixon, G.; Robichon, N.; Robin, C.; Roelens, M.; Rohrbasser, L.;
Romero-Gómez, M.; Rowell, N.; Royer, F.; Rybicki, K. A.; Sadowski,
G.; Sagristà Sellés, A.; Sahlmann, J.; Salgado, J.; Salguero, E.;
Samaras, N.; Sanchez Gimenez, V.; Sanna, N.; Santoveña, R.; Sarasso,
M.; Schultheis, M.; Sciacca, E.; Segol, M.; Segovia, J. C.; Ségransan,
D.; Semeux, D.; Shahaf, S.; Siddiqui, H. I.; Siebert, A.; Siltala,
L.; Slezak, E.; Smart, R. L.; Solano, E.; Solitro, F.; Souami, D.;
Souchay, J.; Spagna, A.; Spoto, F.; Steele, I. A.; Steidelmüller, H.;
Stephenson, C. A.; Süveges, M.; Szabados, L.; Szegedi-Elek, E.; Taris,
F.; Tauran, G.; Taylor, M. B.; Teixeira, R.; Thuillot, W.; Tonello, N.;
Torra, F.; Torra, J.; Turon, C.; Unger, N.; Vaillant, M.; van Dillen,
E.; Vanel, O.; Vecchiato, A.; Viala, Y.; Vicente, D.; Voutsinas,
S.; Weiler, M.; Wevers, T.; Wyrzykowski, Ł.; Yoldas, A.; Yvard, P.;
Zhao, H.; Zorec, J.; Zucker, S.; Zurbach, C.; Zwitter, T.
Bibcode: 2021A&A...650C...3G
Altcode:
No abstract at ADS
Title: Gaia Early Data Release 3. Structure and properties of the
Magellanic Clouds
Authors: Gaia Collaboration; Luri, X.; Chemin, L.; Clementini,
G.; Delgado, H. E.; McMillan, P. J.; Romero-Gómez, M.; Balbinot,
E.; Castro-Ginard, A.; Mor, R.; Ripepi, V.; Sarro, L. M.; Cioni,
M. -R. L.; Fabricius, C.; Garofalo, A.; Helmi, A.; Muraveva, T.;
Brown, A. G. A.; Vallenari, A.; Prusti, T.; de Bruijne, J. H. J.;
Babusiaux, C.; Biermann, M.; Creevey, O. L.; Evans, D. W.; Eyer,
L.; Hutton, A.; Jansen, F.; Jordi, C.; Klioner, S. A.; Lammers, U.;
Lindegren, L.; Mignard, F.; Panem, C.; Pourbaix, D.; Randich, S.;
Sartoretti, P.; Soubiran, C.; Walton, N. A.; Arenou, F.; Bailer-Jones,
C. A. L.; Bastian, U.; Cropper, M.; Drimmel, R.; Katz, D.; Lattanzi,
M. G.; van Leeuwen, F.; Bakker, J.; Castañeda, J.; De Angeli, F.;
Ducourant, C.; Fouesneau, M.; Frémat, Y.; Guerra, R.; Guerrier, A.;
Guiraud, J.; Jean-Antoine Piccolo, A.; Masana, E.; Messineo, R.;
Mowlavi, N.; Nicolas, C.; Nienartowicz, K.; Pailler, F.; Panuzzo,
P.; Riclet, F.; Roux, W.; Seabroke, G. M.; Sordo, R.; Tanga, P.;
Thévenin, F.; Gracia-Abril, G.; Portell, J.; Teyssier, D.; Altmann,
M.; Andrae, R.; Bellas-Velidis, I.; Benson, K.; Berthier, J.; Blomme,
R.; Brugaletta, E.; Burgess, P. W.; Busso, G.; Carry, B.; Cellino,
A.; Cheek, N.; Damerdji, Y.; Davidson, M.; Delchambre, L.; Dell'Oro,
A.; Fernández-Hernández, J.; Galluccio, L.; García-Lario, P.;
Garcia-Reinaldos, M.; González-Núñez, J.; Gosset, E.; Haigron, R.;
Halbwachs, J. -L.; Hambly, N. C.; Harrison, D. L.; Hatzidimitriou,
D.; Heiter, U.; Hernández, J.; Hestroffer, D.; Hodgkin, S. T.; Holl,
B.; Janßen, K.; Jevardat de Fombelle, G.; Jordan, S.; Krone-Martins,
A.; Lanzafame, A. C.; Löffler, W.; Lorca, A.; Manteiga, M.; Marchal,
O.; Marrese, P. M.; Moitinho, A.; Mora, A.; Muinonen, K.; Osborne, P.;
Pancino, E.; Pauwels, T.; Recio-Blanco, A.; Richards, P. J.; Riello,
M.; Rimoldini, L.; Robin, A. C.; Roegiers, T.; Rybizki, J.; Siopis,
C.; Smith, M.; Sozzetti, A.; Ulla, A.; Utrilla, E.; van Leeuwen, M.;
van Reeven, W.; Abbas, U.; Abreu Aramburu, A.; Accart, S.; Aerts, C.;
Aguado, J. J.; Ajaj, M.; Altavilla, G.; Álvarez, M. A.; Álvarez
Cid-Fuentes, J.; Alves, J.; Anderson, R. I.; Anglada Varela, E.;
Antoja, T.; Audard, M.; Baines, D.; Baker, S. G.; Balaguer-Núñez,
L.; Balog, Z.; Barache, C.; Barbato, D.; Barros, M.; Barstow, M. A.;
Bartolomé, S.; Bassilana, J. -L.; Bauchet, N.; Baudesson-Stella, A.;
Becciani, U.; Bellazzini, M.; Bernet, M.; Bertone, S.; Bianchi, L.;
Blanco-Cuaresma, S.; Boch, T.; Bombrun, A.; Bossini, D.; Bouquillon,
S.; Bragaglia, A.; Bramante, L.; Breedt, E.; Bressan, A.; Brouillet,
N.; Bucciarelli, B.; Burlacu, A.; Busonero, D.; Butkevich, A. G.;
Buzzi, R.; Caffau, E.; Cancelliere, R.; Cánovas, H.; Cantat-Gaudin,
T.; Carballo, R.; Carlucci, T.; Carnerero, M. I.; Carrasco, J. M.;
Casamiquela, L.; Castellani, M.; Castro Sampol, P.; Chaoul, L.;
Charlot, P.; Chiavassa, A.; Comoretto, G.; Cooper, W. J.; Cornez,
T.; Cowell, S.; Crifo, F.; Crosta, M.; Crowley, C.; Dafonte, C.;
Dapergolas, A.; David, M.; David, P.; de Laverny, P.; De Luise, F.;
De March, R.; De Ridder, J.; de Souza, R.; de Teodoro, P.; de Torres,
A.; del Peloso, E. F.; del Pozo, E.; Delgado, A.; Delisle, J. -B.;
Di Matteo, P.; Diakite, S.; Diener, C.; Distefano, E.; Dolding,
C.; Eappachen, D.; Enke, H.; Esquej, P.; Fabre, C.; Fabrizio, M.;
Faigler, S.; Fedorets, G.; Fernique, P.; Fienga, A.; Figueras, F.;
Fouron, C.; Fragkoudi, F.; Fraile, E.; Franke, F.; Gai, M.; Garabato,
D.; Garcia-Gutierrez, A.; García-Torres, M.; Gavras, P.; Gerlach,
E.; Geyer, R.; Giacobbe, P.; Gilmore, G.; Girona, S.; Giuffrida, G.;
Gomez, A.; Gonzalez-Santamaria, I.; González-Vidal, J. J.; Granvik,
M.; Gutiérrez-Sánchez, R.; Guy, L. P.; Hauser, M.; Haywood, M.;
Hidalgo, S. L.; Hilger, T.; Hładczuk, N.; Hobbs, D.; Holland, G.;
Huckle, H. E.; Jasniewicz, G.; Jonker, P. G.; Juaristi Campillo, J.;
Julbe, F.; Karbevska, L.; Kervella, P.; Khanna, S.; Kochoska, A.;
Kontizas, M.; Kordopatis, G.; Korn, A. J.; Kostrzewa-Rutkowska, Z.;
Kruszyńska, K.; Lambert, S.; Lanza, A. F.; Lasne, Y.; Le Campion,
J. -F.; Le Fustec, Y.; Lebreton, Y.; Lebzelter, T.; Leccia, S.;
Leclerc, N.; Lecoeur-Taibi, I.; Liao, S.; Licata, E.; Lindstrøm,
H. E. P.; Lister, T. A.; Livanou, E.; Lobel, A.; Madrero Pardo, P.;
Managau, S.; Mann, R. G.; Marchant, J. M.; Marconi, M.; Marcos Santos,
M. M. S.; Marinoni, S.; Marocco, F.; Marshall, D. J.; Martin Polo, L.;
Martín-Fleitas, J. M.; Masip, A.; Massari, D.; Mastrobuono-Battisti,
A.; Mazeh, T.; Messina, S.; Michalik, D.; Millar, N. R.; Mints, A.;
Molina, D.; Molinaro, R.; Molnár, L.; Montegriffo, P.; Morbidelli,
R.; Morel, T.; Morris, D.; Mulone, A. F.; Munoz, D.; Murphy,
C. P.; Musella, I.; Noval, L.; Ordénovic, C.; Orrù, G.; Osinde,
J.; Pagani, C.; Pagano, I.; Palaversa, L.; Palicio, P. A.; Panahi,
A.; Pawlak, M.; Peñalosa Esteller, X.; Penttilä, A.; Piersimoni,
A. M.; Pineau, F. -X.; Plachy, E.; Plum, G.; Poggio, E.; Poretti,
E.; Poujoulet, E.; Prša, A.; Pulone, L.; Racero, E.; Ragaini, S.;
Rainer, M.; Raiteri, C. M.; Rambaux, N.; Ramos, P.; Ramos-Lerate,
M.; Re Fiorentin, P.; Regibo, S.; Reylé, C.; Riva, A.; Rixon,
G.; Robichon, N.; Robin, C.; Roelens, M.; Rohrbasser, L.; Rowell,
N.; Royer, F.; Rybicki, K. A.; Sadowski, G.; Sagristà Sellés,
A.; Sahlmann, J.; Salgado, J.; Salguero, E.; Samaras, N.; Gimenez,
V. Sanchez; Sanna, N.; Santoveña, R.; Sarasso, M.; Schultheis, M.;
Sciacca, E.; Segol, M.; Segovia, J. C.; Ségransan, D.; Semeux, D.;
Siddiqui, H. I.; Siebert, A.; Siltala, L.; Slezak, E.; Smart, R. L.;
Solano, E.; Solitro, F.; Souami, D.; Souchay, J.; Spagna, A.; Spoto,
F.; Steele, I. A.; Steidelmüller, H.; Stephenson, C. A.; Süveges,
M.; Szabados, L.; Szegedi-Elek, E.; Taris, F.; Tauran, G.; Taylor,
M. B.; Teixeira, R.; Thuillot, W.; Tonello, N.; Torra, F.; Torra,
J.; Turon, C.; Unger, N.; Vaillant, M.; van Dillen, E.; Vanel, O.;
Vecchiato, A.; Viala, Y.; Vicente, D.; Voutsinas, S.; Weiler, M.;
Wevers, T.; Wyrzykowski, Ł.; Yoldas, A.; Yvard, P.; Zhao, H.; Zorec,
J.; Zucker, S.; Zurbach, C.; Zwitter, T.
Bibcode: 2021A&A...649A...7G
Altcode: 2020arXiv201201771G
Context. This work is part of the Gaia Data Processing and Analysis
Consortium papers published with the Gaia Early Data Release 3
(EDR3). It is one of the demonstration papers aiming to highlight
the improvements and quality of the newly published data by applying
them to a scientific case.
Aims: We use the Gaia EDR3 data to
study the structure and kinematics of the Magellanic Clouds. The large
distance to the Clouds is a challenge for the Gaia astrometry. The
Clouds lie at the very limits of the usability of the Gaia data,
which makes the Clouds an excellent case study for evaluating the
quality and properties of the Gaia data.
Methods: The basis
of our work are two samples selected to provide a representation as
clean as possible of the stars of the Large Magellanic Cloud (LMC)
and the Small Magellanic Cloud (SMC). The selection used criteria
based on position, parallax, and proper motions to remove foreground
contamination from the Milky Way, and allowed the separation of the
stars of both Clouds. From these two samples we defined a series
of subsamples based on cuts in the colour-magnitude diagram; these
subsamples were used to select stars in a common evolutionary phase and
can also be used as approximate proxies of a selection by age.
Results: We compared the Gaia Data Release 2 and Gaia EDR3 performances
in the study of the Magellanic Clouds and show the clear improvements
in precision and accuracy in the new release. We also show that the
systematics still present in the data make the determination of the
3D geometry of the LMC a difficult endeavour; this is at the very
limit of the usefulness of the Gaia EDR3 astrometry, but it may become
feasible with the use of additional external data. We derive radial
and tangential velocity maps and global profiles for the LMC for the
several subsamples we defined. To our knowledge, this is the first
time that the two planar components of the ordered and random motions
are derived for multiple stellar evolutionary phases in a galactic disc
outside the Milky Way, showing the differences between younger and older
phases. We also analyse the spatial structure and motions in the central
region, the bar, and the disc, providing new insightsinto features and
kinematics. Finally, we show that the Gaia EDR3 data allows clearly
resolving the Magellanic Bridge, and we trace the density and velocity
flow of the stars from the SMC towards the LMC not only globally,
but also separately for young and evolved populations. This allows
us to confirm an evolved population in the Bridge that is slightly
shift from the younger population. Additionally, we were able to
study the outskirts of both Magellanic Clouds, in which we detected
some well-known features and indications of new ones. Velocity
profiles are only available at the CDS via anonymous ftp to cdsarc.u-strasbg.fr
(ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/649/A7
Title: Gaia Early Data Release 3. Summary of the contents and survey
properties
Authors: Gaia Collaboration; Brown, A. G. A.; Vallenari, A.;
Prusti, T.; de Bruijne, J. H. J.; Babusiaux, C.; Biermann, M.;
Creevey, O. L.; Evans, D. W.; Eyer, L.; Hutton, A.; Jansen, F.;
Jordi, C.; Klioner, S. A.; Lammers, U.; Lindegren, L.; Luri, X.;
Mignard, F.; Panem, C.; Pourbaix, D.; Randich, S.; Sartoretti, P.;
Soubiran, C.; Walton, N. A.; Arenou, F.; Bailer-Jones, C. A. L.;
Bastian, U.; Cropper, M.; Drimmel, R.; Katz, D.; Lattanzi, M. G.;
van Leeuwen, F.; Bakker, J.; Cacciari, C.; Castañeda, J.; De Angeli,
F.; Ducourant, C.; Fabricius, C.; Fouesneau, M.; Frémat, Y.; Guerra,
R.; Guerrier, A.; Guiraud, J.; Jean-Antoine Piccolo, A.; Masana, E.;
Messineo, R.; Mowlavi, N.; Nicolas, C.; Nienartowicz, K.; Pailler,
F.; Panuzzo, P.; Riclet, F.; Roux, W.; Seabroke, G. M.; Sordo, R.;
Tanga, P.; Thévenin, F.; Gracia-Abril, G.; Portell, J.; Teyssier,
D.; Altmann, M.; Andrae, R.; Bellas-Velidis, I.; Benson, K.; Berthier,
J.; Blomme, R.; Brugaletta, E.; Burgess, P. W.; Busso, G.; Carry, B.;
Cellino, A.; Cheek, N.; Clementini, G.; Damerdji, Y.; Davidson, M.;
Delchambre, L.; Dell'Oro, A.; Fernández-Hernández, J.; Galluccio,
L.; García-Lario, P.; Garcia-Reinaldos, M.; González-Núñez, J.;
Gosset, E.; Haigron, R.; Halbwachs, J. -L.; Hambly, N. C.; Harrison,
D. L.; Hatzidimitriou, D.; Heiter, U.; Hernández, J.; Hestroffer,
D.; Hodgkin, S. T.; Holl, B.; Janßen, K.; Jevardat de Fombelle, G.;
Jordan, S.; Krone-Martins, A.; Lanzafame, A. C.; Löffler, W.; Lorca,
A.; Manteiga, M.; Marchal, O.; Marrese, P. M.; Moitinho, A.; Mora, A.;
Muinonen, K.; Osborne, P.; Pancino, E.; Pauwels, T.; Petit, J. -M.;
Recio-Blanco, A.; Richards, P. J.; Riello, M.; Rimoldini, L.; Robin,
A. C.; Roegiers, T.; Rybizki, J.; Sarro, L. M.; Siopis, C.; Smith, M.;
Sozzetti, A.; Ulla, A.; Utrilla, E.; van Leeuwen, M.; van Reeven, W.;
Abbas, U.; Abreu Aramburu, A.; Accart, S.; Aerts, C.; Aguado, J. J.;
Ajaj, M.; Altavilla, G.; Álvarez, M. A.; Álvarez Cid-Fuentes, J.;
Alves, J.; Anderson, R. I.; Anglada Varela, E.; Antoja, T.; Audard, M.;
Baines, D.; Baker, S. G.; Balaguer-Núñez, L.; Balbinot, E.; Balog,
Z.; Barache, C.; Barbato, D.; Barros, M.; Barstow, M. A.; Bartolomé,
S.; Bassilana, J. -L.; Bauchet, N.; Baudesson-Stella, A.; Becciani, U.;
Bellazzini, M.; Bernet, M.; Bertone, S.; Bianchi, L.; Blanco-Cuaresma,
S.; Boch, T.; Bombrun, A.; Bossini, D.; Bouquillon, S.; Bragaglia, A.;
Bramante, L.; Breedt, E.; Bressan, A.; Brouillet, N.; Bucciarelli,
B.; Burlacu, A.; Busonero, D.; Butkevich, A. G.; Buzzi, R.; Caffau,
E.; Cancelliere, R.; Cánovas, H.; Cantat-Gaudin, T.; Carballo, R.;
Carlucci, T.; Carnerero, M. I.; Carrasco, J. M.; Casamiquela, L.;
Castellani, M.; Castro-Ginard, A.; Castro Sampol, P.; Chaoul, L.;
Charlot, P.; Chemin, L.; Chiavassa, A.; Cioni, M. -R. L.; Comoretto,
G.; Cooper, W. J.; Cornez, T.; Cowell, S.; Crifo, F.; Crosta, M.;
Crowley, C.; Dafonte, C.; Dapergolas, A.; David, M.; David, P.; de
Laverny, P.; De Luise, F.; De March, R.; De Ridder, J.; de Souza,
R.; de Teodoro, P.; de Torres, A.; del Peloso, E. F.; del Pozo, E.;
Delbo, M.; Delgado, A.; Delgado, H. E.; Delisle, J. -B.; Di Matteo,
P.; Diakite, S.; Diener, C.; Distefano, E.; Dolding, C.; Eappachen,
D.; Edvardsson, B.; Enke, H.; Esquej, P.; Fabre, C.; Fabrizio, M.;
Faigler, S.; Fedorets, G.; Fernique, P.; Fienga, A.; Figueras, F.;
Fouron, C.; Fragkoudi, F.; Fraile, E.; Franke, F.; Gai, M.; Garabato,
D.; Garcia-Gutierrez, A.; García-Torres, M.; Garofalo, A.; Gavras,
P.; Gerlach, E.; Geyer, R.; Giacobbe, P.; Gilmore, G.; Girona,
S.; Giuffrida, G.; Gomel, R.; Gomez, A.; Gonzalez-Santamaria, I.;
González-Vidal, J. J.; Granvik, M.; Gutiérrez-Sánchez, R.; Guy,
L. P.; Hauser, M.; Haywood, M.; Helmi, A.; Hidalgo, S. L.; Hilger,
T.; Hładczuk, N.; Hobbs, D.; Holland, G.; Huckle, H. E.; Jasniewicz,
G.; Jonker, P. G.; Juaristi Campillo, J.; Julbe, F.; Karbevska, L.;
Kervella, P.; Khanna, S.; Kochoska, A.; Kontizas, M.; Kordopatis, G.;
Korn, A. J.; Kostrzewa-Rutkowska, Z.; Kruszyńska, K.; Lambert, S.;
Lanza, A. F.; Lasne, Y.; Le Campion, J. -F.; Le Fustec, Y.; Lebreton,
Y.; Lebzelter, T.; Leccia, S.; Leclerc, N.; Lecoeur-Taibi, I.; Liao,
S.; Licata, E.; Lindstrøm, E. P.; Lister, T. A.; Livanou, E.; Lobel,
A.; Madrero Pardo, P.; Managau, S.; Mann, R. G.; Marchant, J. M.;
Marconi, M.; Marcos Santos, M. M. S.; Marinoni, S.; Marocco, F.;
Marshall, D. J.; Martin Polo, L.; Martín-Fleitas, J. M.; Masip, A.;
Massari, D.; Mastrobuono-Battisti, A.; Mazeh, T.; McMillan, P. J.;
Messina, S.; Michalik, D.; Millar, N. R.; Mints, A.; Molina, D.;
Molinaro, R.; Molnár, L.; Montegriffo, P.; Mor, R.; Morbidelli, R.;
Morel, T.; Morris, D.; Mulone, A. F.; Munoz, D.; Muraveva, T.; Murphy,
C. P.; Musella, I.; Noval, L.; Ordénovic, C.; Orrù, G.; Osinde,
J.; Pagani, C.; Pagano, I.; Palaversa, L.; Palicio, P. A.; Panahi,
A.; Pawlak, M.; Peñalosa Esteller, X.; Penttilä, A.; Piersimoni,
A. M.; Pineau, F. -X.; Plachy, E.; Plum, G.; Poggio, E.; Poretti,
E.; Poujoulet, E.; Prša, A.; Pulone, L.; Racero, E.; Ragaini, S.;
Rainer, M.; Raiteri, C. M.; Rambaux, N.; Ramos, P.; Ramos-Lerate,
M.; Re Fiorentin, P.; Regibo, S.; Reylé, C.; Ripepi, V.; Riva, A.;
Rixon, G.; Robichon, N.; Robin, C.; Roelens, M.; Rohrbasser, L.;
Romero-Gómez, M.; Rowell, N.; Royer, F.; Rybicki, K. A.; Sadowski,
G.; Sagristà Sellés, A.; Sahlmann, J.; Salgado, J.; Salguero, E.;
Samaras, N.; Sanchez Gimenez, V.; Sanna, N.; Santoveña, R.; Sarasso,
M.; Schultheis, M.; Sciacca, E.; Segol, M.; Segovia, J. C.; Ségransan,
D.; Semeux, D.; Shahaf, S.; Siddiqui, H. I.; Siebert, A.; Siltala,
L.; Slezak, E.; Smart, R. L.; Solano, E.; Solitro, F.; Souami, D.;
Souchay, J.; Spagna, A.; Spoto, F.; Steele, I. A.; Steidelmüller,
H.; Stephenson, C. A.; Süveges, M.; Szabados, L.; Szegedi-Elek, E.;
Taris, F.; Tauran, G.; Taylor, M. B.; Teixeira, R.; Thuillot, W.;
Tonello, N.; Torra, F.; Torra, J.; Turon, C.; Unger, N.; Vaillant,
M.; van Dillen, E.; Vanel, O.; Vecchiato, A.; Viala, Y.; Vicente, D.;
Voutsinas, S.; Weiler, M.; Wevers, T.; Wyrzykowski, Ł.; Yoldas, A.;
Yvard, P.; Zhao, H.; Zorec, J.; Zucker, S.; Zurbach, C.; Zwitter, T.
Bibcode: 2021A&A...649A...1G
Altcode: 2020arXiv201201533G
Context. We present the early installment of the third Gaia data
release, Gaia EDR3, consisting of astrometry and photometry for 1.8
billion sources brighter than magnitude 21, complemented with the
list of radial velocities from Gaia DR2.
Aims: A summary of
the contents of Gaia EDR3 is presented, accompanied by a discussion
on the differences with respect to Gaia DR2 and an overview of the
main limitations which are present in the survey. Recommendations
are made on the responsible use of Gaia EDR3 results.
Methods:
The raw data collected with the Gaia instruments during the first 34
months of the mission have been processed by the Gaia Data Processing
and Analysis Consortium and turned into this early third data release,
which represents a major advance with respect to Gaia DR2 in terms of
astrometric and photometric precision, accuracy, and homogeneity.
Results: Gaia EDR3 contains celestial positions and the apparent
brightness in G for approximately 1.8 billion sources. For 1.5 billion
of those sources, parallaxes, proper motions, and the (GBP
− GRP) colour are also available. The passbands for
G, GBP, and GRP are provided as part of the
release. For ease of use, the 7 million radial velocities from Gaia
DR2 are included in this release, after the removal of a small number
of spurious values. New radial velocities will appear as part of Gaia
DR3. Finally, Gaia EDR3 represents an updated materialisation of the
celestial reference frame (CRF) in the optical, the Gaia-CRF3, which
is based solely on extragalactic sources. The creation of the source
list for Gaia EDR3 includes enhancements that make it more robust with
respect to high proper motion stars, and the disturbing effects of
spurious and partially resolved sources. The source list is largely the
same as that for Gaia DR2, but it does feature new sources and there
are some notable changes. The source list will not change for Gaia
DR3.
Conclusions: Gaia EDR3 represents a significant advance
over Gaia DR2, with parallax precisions increased by 30 per cent,
proper motion precisions increased by a factor of 2, and the systematic
errors in the astrometry suppressed by 30-40% for the parallaxes and
by a factor ~2.5 for the proper motions. The photometry also features
increased precision, but above all much better homogeneity across
colour, magnitude, and celestial position. A single passband for G,
GBP, and GRP is valid over the entire magnitude
and colour range, with no systematics above the 1% level
Title: Gaia Early Data Release 3. The astrometric solution
Authors: Lindegren, L.; Klioner, S. A.; Hernández, J.; Bombrun,
A.; Ramos-Lerate, M.; Steidelmüller, H.; Bastian, U.; Biermann,
M.; de Torres, A.; Gerlach, E.; Geyer, R.; Hilger, T.; Hobbs, D.;
Lammers, U.; McMillan, P. J.; Stephenson, C. A.; Castañeda, J.;
Davidson, M.; Fabricius, C.; Gracia-Abril, G.; Portell, J.; Rowell,
N.; Teyssier, D.; Torra, F.; Bartolomé, S.; Clotet, M.; Garralda, N.;
González-Vidal, J. J.; Torra, J.; Abbas, U.; Altmann, M.; Anglada
Varela, E.; Balaguer-Núñez, L.; Balog, Z.; Barache, C.; Becciani,
U.; Bernet, M.; Bertone, S.; Bianchi, L.; Bouquillon, S.; Brown,
A. G. A.; Bucciarelli, B.; Busonero, D.; Butkevich, A. G.; Buzzi,
R.; Cancelliere, R.; Carlucci, T.; Charlot, P.; Cioni, M. -R. L.;
Crosta, M.; Crowley, C.; del Peloso, E. F.; del Pozo, E.; Drimmel,
R.; Esquej, P.; Fienga, A.; Fraile, E.; Gai, M.; Garcia-Reinaldos,
M.; Guerra, R.; Hambly, N. C.; Hauser, M.; Janßen, K.; Jordan, S.;
Kostrzewa-Rutkowska, Z.; Lattanzi, M. G.; Liao, S.; Licata, E.; Lister,
T. A.; Löffler, W.; Marchant, J. M.; Masip, A.; Mignard, F.; Mints,
A.; Molina, D.; Mora, A.; Morbidelli, R.; Murphy, C. P.; Pagani, C.;
Panuzzo, P.; Peñalosa Esteller, X.; Poggio, E.; Re Fiorentin, P.;
Riva, A.; Sagristà Sellés, A.; Sanchez Gimenez, V.; Sarasso, M.;
Sciacca, E.; Siddiqui, H. I.; Smart, R. L.; Souami, D.; Spagna, A.;
Steele, I. A.; Taris, F.; Utrilla, E.; van Reeven, W.; Vecchiato, A.
Bibcode: 2021A&A...649A...2L
Altcode: 2020arXiv201203380L
Context. Gaia Early Data Release 3 (Gaia EDR3) contains results
for 1.812 billion sources in the magnitude range G = 3-21 based on
observations collected by the European Space Agency Gaia satellite
during the first 34 months of its operational phase.
Aims:
We describe the input data, the models, and the processing used for
the astrometric content of Gaia EDR3, as well as the validation of
these results performed within the astrometry task.
Methods:
The processing broadly followed the same procedures as for Gaia DR2, but
with significant improvements to the modelling of observations. For the
first time in the Gaia data processing, colour-dependent calibrations
of the line- and point-spread functions have been used for sources
with well-determined colours from DR2. In the astrometric processing
these sources obtained five-parameter solutions, whereas other sources
were processed using a special calibration that allowed a pseudocolour
to be estimated as the sixth astrometric parameter. Compared with
DR2, the astrometric calibration models have been extended, and the
spin-related distortion model includes a self-consistent determination
of basic-angle variations, improving the global parallax zero point.
Results: Gaia EDR3 gives full astrometric data (positions at epoch
J2016.0, parallaxes, and proper motions) for 1.468 billion sources (585
millionwith five-parameter solutions, 882 million with six parameters),
and mean positions at J2016.0 for an additional 344 million.Solutions
with five parameters are generally more accurate than six-parameter
solutions, and are available for 93% of the sources brighter than the
17th magnitude. The median uncertainty in parallax and annual proper
motion is 0.02-0.03 mas at magnitude G = 9-14, and around 0.5 mas at G
= 20. Extensive characterisation of the statistical properties of the
solutions is provided, including the estimated angular power spectrum
of parallax bias from the quasars.
Title: Gaia Early Data Release 3. The Galactic anticentre
Authors: Gaia Collaboration; Antoja, T.; McMillan, P. J.; Kordopatis,
G.; Ramos, P.; Helmi, A.; Balbinot, E.; Cantat-Gaudin, T.; Chemin, L.;
Figueras, F.; Jordi, C.; Khanna, S.; Romero-Gómez, M.; Seabroke,
G. M.; Brown, A. G. A.; Vallenari, A.; Prusti, T.; de Bruijne,
J. H. J.; Babusiaux, C.; Biermann, M.; Creevey, O. L.; Evans,
D. W.; Eyer, L.; Hutton, A.; Jansen, F.; Klioner, S. A.; Lammers,
U.; Lindegren, L.; Luri, X.; Mignard, F.; Panem, C.; Pourbaix, D.;
Randich, S.; Sartoretti, P.; Soubiran, C.; Walton, N. A.; Arenou, F.;
Bailer-Jones, C. A. L.; Bastian, U.; Cropper, M.; Drimmel, R.; Katz,
D.; Lattanzi, M. G.; van Leeuwen, F.; Bakker, J.; Castañeda, J.;
De Angeli, F.; Ducourant, C.; Fabricius, C.; Fouesneau, M.; Frémat,
Y.; Guerra, R.; Guerrier, A.; Guiraud, J.; Jean-Antoine Piccolo, A.;
Masana, E.; Messineo, R.; Mowlavi, N.; Nicolas, C.; Nienartowicz, K.;
Pailler, F.; Panuzzo, P.; Riclet, F.; Roux, W.; Sordo, R.; Tanga,
P.; Thévenin, F.; Gracia-Abril, G.; Portell, J.; Teyssier, D.;
Altmann, M.; Andrae, R.; Bellas-Velidis, I.; Benson, K.; Berthier,
J.; Blomme, R.; Brugaletta, E.; Burgess, P. W.; Busso, G.; Carry, B.;
Cellino, A.; Cheek, N.; Clementini, G.; Damerdji, Y.; Davidson, M.;
Delchambre, L.; Dell'Oro, A.; Fernández-Hernández, J.; Galluccio,
L.; García-Lario, P.; Garcia-Reinaldos, M.; González-Núñez, J.;
Gosset, E.; Haigron, R.; Halbwachs, J. -L.; Hambly, N. C.; Harrison,
D. L.; Hatzidimitriou, D.; Heiter, U.; Hernández, J.; Hestroffer,
D.; Hodgkin, S. T.; Holl, B.; Janßen, K.; Jevardat de Fombelle, G.;
Jordan, S.; Krone-Martins, A.; Lanzafame, A. C.; Löffler, W.; Lorca,
A.; Manteiga, M.; Marchal, O.; Marrese, P. M.; Moitinho, A.; Mora, A.;
Muinonen, K.; Osborne, P.; Pancino, E.; Pauwels, T.; Recio-Blanco, A.;
Richards, P. J.; Riello, M.; Rimoldini, L.; Robin, A. C.; Roegiers,
T.; Rybizki, J.; Sarro, L. M.; Siopis, C.; Smith, M.; Sozzetti, A.;
Ulla, A.; Utrilla, E.; van Leeuwen, M.; van Reeven, W.; Abbas, U.;
Abreu Aramburu, A.; Accart, S.; Aerts, C.; Aguado, J. J.; Ajaj, M.;
Altavilla, G.; Álvarez, M. A.; Álvarez Cid-Fuentes, J.; Alves,
J.; Anderson, R. I.; Varela, E. Anglada; Audard, M.; Baines, D.;
Baker, S. G.; Balaguer-Núñez, L.; Balog, Z.; Barache, C.; Barbato,
D.; Barros, M.; Barstow, M. A.; Bartolomé, S.; Bassilana, J. -L.;
Bauchet, N.; Baudesson-Stella, A.; Becciani, U.; Bellazzini, M.;
Bernet, M.; Bertone, S.; Bianchi, L.; Blanco-Cuaresma, S.; Boch, T.;
Bombrun, A.; Bossini, D.; Bouquillon, S.; Bragaglia, A.; Bramante, L.;
Breedt, E.; Bressan, A.; Brouillet, N.; Bucciarelli, B.; Burlacu, A.;
Busonero, D.; Butkevich, A. G.; Buzzi, R.; Caffau, E.; Cancelliere,
R.; Cánovas, H.; Carballo, R.; Carlucci, T.; Carnerero, M. I.;
Carrasco, J. M.; Casamiquela, L.; Castellani, M.; Castro-Ginard, A.;
Castro Sampol, P.; Chaoul, L.; Charlot, P.; Chiavassa, A.; Cioni,
M. -R. L.; Comoretto, G.; Cooper, W. J.; Cornez, T.; Cowell, S.;
Crifo, F.; Crosta, M.; Crowley, C.; Dafonte, C.; Dapergolas, A.;
David, M.; David, P.; de Laverny, P.; De Luise, F.; De March, R.; De
Ridder, J.; de Souza, R.; de Teodoro, P.; de Torres, A.; del Peloso,
E. F.; del Pozo, E.; Delgado, A.; Delgado, H. E.; Delisle, J. -B.;
Di Matteo, P.; Diakite, S.; Diener, C.; Distefano, E.; Dolding, C.;
Eappachen, D.; Enke, H.; Esquej, P.; Fabre, C.; Fabrizio, M.; Faigler,
S.; Fedorets, G.; Fernique, P.; Fienga, A.; Fouron, C.; Fragkoudi, F.;
Fraile, E.; Franke, F.; Gai, M.; Garabato, D.; Garcia-Gutierrez, A.;
García-Torres, M.; Garofalo, A.; Gavras, P.; Gerlach, E.; Geyer,
R.; Giacobbe, P.; Gilmore, G.; Girona, S.; Giuffrida, G.; Gomez,
A.; Gonzalez-Santamaria, I.; González-Vidal, J. J.; Granvik, M.;
Gutiérrez-Sánchez, R.; Guy, L. P.; Hauser, M.; Haywood, M.; Hidalgo,
S. L.; Hilger, T.; Hładczuk, N.; Hobbs, D.; Holland, G.; Huckle,
H. E.; Jasniewicz, G.; Jonker, P. G.; Juaristi Campillo, J.; Julbe,
F.; Karbevska, L.; Kervella, P.; Kochoska, A.; Kontizas, M.; Korn,
A. J.; Kostrzewa-Rutkowska, Z.; Kruszyńska, K.; Lambert, S.; Lanza,
A. F.; Lasne, Y.; Le Campion, J. -F.; Le Fustec, Y.; Lebreton, Y.;
Lebzelter, T.; Leccia, S.; Leclerc, N.; Lecoeur-Taibi, I.; Liao, S.;
Licata, E.; Lindstrøm, H. E. P.; Lister, T. A.; Livanou, E.; Lobel,
A.; Madrero Pardo, P.; Managau, S.; Mann, R. G.; Marchant, J. M.;
Marconi, M.; Marcos Santos, M. M. S.; Marinoni, S.; Marocco, F.;
Marshall, D. J.; Martin Polo, L.; Martín-Fleitas, J. M.; Masip,
A.; Massari, D.; Mastrobuono-Battisti, A.; Mazeh, T.; Messina,
S.; Michalik, D.; Millar, N. R.; Mints, A.; Molina, D.; Molinaro,
R.; Molnár, L.; Montegriffo, P.; Mor, R.; Morbidelli, R.; Morel,
T.; Morris, D.; Mulone, A. F.; Munoz, D.; Muraveva, T.; Murphy,
C. P.; Musella, I.; Noval, L.; Ordénovic, C.; Orrù, G.; Osinde,
J.; Pagani, C.; Pagano, I.; Palaversa, L.; Palicio, P. A.; Panahi,
A.; Pawlak, M.; Peñalosa Esteller, X.; Penttilä, A.; Piersimoni,
A. M.; Pineau, F. -X.; Plachy, E.; Plum, G.; Poggio, E.; Poretti, E.;
Poujoulet, E.; Prša, A.; Pulone, L.; Racero, E.; Ragaini, S.; Rainer,
M.; Raiteri, C. M.; Rambaux, N.; Ramos-Lerate, M.; Re Fiorentin, P.;
Regibo, S.; Reylé, C.; Ripepi, V.; Riva, A.; Rixon, G.; Robichon,
N.; Robin, C.; Roelens, M.; Rohrbasser, L.; Rowell, N.; Royer, F.;
Rybicki, K. A.; Sadowski, G.; Sagristà Sellés, A.; Sahlmann, J.;
Salgado, J.; Salguero, E.; Samaras, N.; Sanchez Gimenez, V.; Sanna,
N.; Santoveña, R.; Sarasso, M.; Schultheis, M.; Sciacca, E.; Segol,
M.; Segovia, J. C.; Ségransan, D.; Semeux, D.; Siddiqui, H. I.;
Siebert, A.; Siltala, L.; Slezak, E.; Smart, R. L.; Solano, E.;
Solitro, F.; Souami, D.; Souchay, J.; Spagna, A.; Spoto, F.; Steele,
I. A.; Steidelmüller, H.; Stephenson, C. A.; Süveges, M.; Szabados,
L.; Szegedi-Elek, E.; Taris, F.; Tauran, G.; Taylor, M. B.; Teixeira,
R.; Thuillot, W.; Tonello, N.; Torra, F.; Torra, J.; Turon, C.; Unger,
N.; Vaillant, M.; van Dillen, E.; Vanel, O.; Vecchiato, A.; Viala,
Y.; Vicente, D.; Voutsinas, S.; Weiler, M.; Wevers, T.; Wyrzykowski,
Ł.; Yoldas, A.; Yvard, P.; Zhao, H.; Zorec, J.; Zucker, S.; Zurbach,
C.; Zwitter, T.
Bibcode: 2021A&A...649A...8G
Altcode: 2021arXiv210105811G
Aims: We aim to demonstrate the scientific potential of the
Gaia Early Data Release 3 (EDR3) for the study of different aspects
of the Milky Way structure and evolution and we provide, at the
same time, a description of several practical aspects of the data
and examples of their usage.
Methods: We used astrometric
positions, proper motions, parallaxes, and photometry from EDR3 to
select different populations and components and to calculate the
distances and velocities in the direction of the anticentre. In this
direction, the Gaia astrometric data alone enable the calculation
of the vertical and azimuthal velocities; also, the extinction is
relatively low compared to other directions in the Galactic plane. We
then explore the disturbances of the current disc, the spatial and
kinematical distributions of early accreted versus in situ stars,
the structures in the outer parts of the disc, and the orbits of open
clusters Berkeley 29 and Saurer 1.
Results: With the improved
astrometry and photometry of EDR3, we find that: (i) the dynamics of the
Galactic disc are very complex with oscillations in the median rotation
and vertical velocities as a function of radius, vertical asymmetries,
and new correlations, including a bimodality with disc stars with large
angular momentum moving vertically upwards from below the plane, and
disc stars with slightly lower angular momentum moving preferentially
downwards; (ii) we resolve the kinematic substructure (diagonal ridges)
in the outer parts of the disc for the first time; (iii) the red
sequence that has been associated with the proto-Galactic disc that
was present at the time of the merger with Gaia-Enceladus-Sausage is
currently radially concentrated up to around 14 kpc, while the blue
sequence that has been associated with debris of the satellite extends
beyond that; (iv) there are density structures in the outer disc,
both above and below the plane, most probably related to Monoceros,
the Anticentre Stream, and TriAnd, for which the Gaia data allow an
exhaustive selection of candidate member stars and dynamical study;
and (v) the open clusters Berkeley 29 and Saurer 1, despite being
located at large distances from the Galactic centre, are on nearly
circular disc-like orbits.
Conclusions: Even with our simple
preliminary exploration of the Gaia EDR3, we demonstrate how, once
again, these data from the European Space Agency are crucial for our
understanding of the different pieces of our Galaxy and their connection
to its global structure and history. Movie is available at https://www.aanda.org
Title: Gaia Early Data Release 3. Acceleration of the Solar System
from Gaia astrometry
Authors: Gaia Collaboration; Klioner, S. A.; Mignard, F.; Lindegren,
L.; Bastian, U.; McMillan, P. J.; Hernández, J.; Hobbs, D.;
Ramos-Lerate, M.; Biermann, M.; Bombrun, A.; de Torres, A.; Gerlach,
E.; Geyer, R.; Hilger, T.; Lammers, U.; Steidelmüller, H.; Stephenson,
C. A.; Brown, A. G. A.; Vallenari, A.; Prusti, T.; de Bruijne,
J. H. J.; Babusiaux, C.; Creevey, O. L.; Evans, D. W.; Eyer, L.;
Hutton, A.; Jansen, F.; Jordi, C.; Luri, X.; Panem, C.; Pourbaix, D.;
Randich, S.; Sartoretti, P.; Soubiran, C.; Walton, N. A.; Arenou, F.;
Bailer-Jones, C. A. L.; Cropper, M.; Drimmel, R.; Katz, D.; Lattanzi,
M. G.; van Leeuwen, F.; Bakker, J.; Castañeda, J.; De Angeli, F.;
Ducourant, C.; Fabricius, C.; Fouesneau, M.; Frémat, Y.; Guerra,
R.; Guerrier, A.; Guiraud, J.; Jean-Antoine Piccolo, A.; Masana, E.;
Messineo, R.; Mowlavi, N.; Nicolas, C.; Nienartowicz, K.; Pailler,
F.; Panuzzo, P.; Riclet, F.; Roux, W.; Seabroke, G. M.; Sordo, R.;
Tanga, P.; Thévenin, F.; Gracia-Abril, G.; Portell, J.; Teyssier,
D.; Altmann, M.; Andrae, R.; Bellas-Velidis, I.; Benson, K.; Berthier,
J.; Blomme, R.; Brugaletta, E.; Burgess, P. W.; Busso, G.; Carry, B.;
Cellino, A.; Cheek, N.; Clementini, G.; Damerdji, Y.; Davidson, M.;
Delchambre, L.; Dell'Oro, A.; Fernández-Hernández, J.; Galluccio,
L.; García-Lario, P.; Garcia-Reinaldos, M.; González-Núñez, J.;
Gosset, E.; Haigron, R.; Halbwachs, J. -L.; Hambly, N. C.; Harrison,
D. L.; Hatzidimitriou, D.; Heiter, U.; Hestroffer, D.; Hodgkin,
S. T.; Holl, B.; Janßen, K.; Jevardat de Fombelle, G.; Jordan,
S.; Krone-Martins, A.; Lanzafame, A. C.; Löffler, W.; Lorca, A.;
Manteiga, M.; Marchal, O.; Marrese, P. M.; Moitinho, A.; Mora, A.;
Muinonen, K.; Osborne, P.; Pancino, E.; Pauwels, T.; Recio-Blanco, A.;
Richards, P. J.; Riello, M.; Rimoldini, L.; Robin, A. C.; Roegiers,
T.; Rybizki, J.; Sarro, L. M.; Siopis, C.; Smith, M.; Sozzetti, A.;
Ulla, A.; Utrilla, E.; van Leeuwen, M.; van Reeven, W.; Abbas, U.;
Abreu Aramburu, A.; Accart, S.; Aerts, C.; Aguado, J. J.; Ajaj, M.;
Altavilla, G.; Álvarez, M. A.; Álvarez Cid-Fuentes, J.; Alves, J.;
Anderson, R. I.; Anglada Varela, E.; Antoja, T.; Audard, M.; Baines,
D.; Baker, S. G.; Balaguer-Núñez, L.; Balbinot, E.; Balog, Z.;
Barache, C.; Barbato, D.; Barros, M.; Barstow, M. A.; Bartolomé, S.;
Bassilana, J. -L.; Bauchet, N.; Baudesson-Stella, A.; Becciani, U.;
Bellazzini, M.; Bernet, M.; Bertone, S.; Bianchi, L.; Blanco-Cuaresma,
S.; Boch, T.; Bossini, D.; Bouquillon, S.; Bramante, L.; Breedt, E.;
Bressan, A.; Brouillet, N.; Bucciarelli, B.; Burlacu, A.; Busonero, D.;
Butkevich, A. G.; Buzzi, R.; Caffau, E.; Cancelliere, R.; Cánovas,
H.; Cantat-Gaudin, T.; Carballo, R.; Carlucci, T.; Carnerero, M. I.;
Carrasco, J. M.; Casamiquela, L.; Castellani, M.; Castro-Ginard, A.;
Castro Sampol, P.; Chaoul, L.; Charlot, P.; Chemin, L.; Chiavassa,
A.; Comoretto, G.; Cooper, W. J.; Cornez, T.; Cowell, S.; Crifo, F.;
Crosta, M.; Crowley, C.; Dafonte, C.; Dapergolas, A.; David, M.;
David, P.; de Laverny, P.; De Luise, F.; De March, R.; De Ridder,
J.; de Souza, R.; de Teodoro, P.; del Peloso, E. F.; del Pozo, E.;
Delgado, A.; Delgado, H. E.; Delisle, J. -B.; Di Matteo, P.; Diakite,
S.; Diener, C.; Distefano, E.; Dolding, C.; Eappachen, D.; Enke,
H.; Esquej, P.; Fabre, C.; Fabrizio, M.; Faigler, S.; Fedorets, G.;
Fernique, P.; Fienga, A.; Figueras, F.; Fouron, C.; Fragkoudi, F.;
Fraile, E.; Franke, F.; Gai, M.; Garabato, D.; Garcia-Gutierrez, A.;
García-Torres, M.; Garofalo, A.; Gavras, P.; Giacobbe, P.; Gilmore,
G.; Girona, S.; Giuffrida, G.; Gomez, A.; Gonzalez-Santamaria, I.;
González-Vidal, J. J.; Granvik, M.; Gutiérrez-Sánchez, R.; Guy,
L. P.; Hauser, M.; Haywood, M.; Helmi, A.; Hidalgo, S. L.; Hładczuk,
N.; Holland, G.; Huckle, H. E.; Jasniewicz, G.; Jonker, P. G.; Juaristi
Campillo, J.; Julbe, F.; Karbevska, L.; Kervella, P.; Khanna, S.;
Kochoska, A.; Kordopatis, G.; Korn, A. J.; Kostrzewa-Rutkowska, Z.;
Kruszyńska, K.; Lambert, S.; Lanza, A. F.; Lasne, Y.; Le Campion,
J. -F.; Le Fustec, Y.; Lebreton, Y.; Lebzelter, T.; Leccia, S.;
Leclerc, N.; Lecoeur-Taibi, I.; Liao, S.; Licata, E.; Lindstrøm,
H. E. P.; Lister, T. A.; Livanou, E.; Lobel, A.; Madrero Pardo, P.;
Managau, S.; Mann, R. G.; Marchant, J. M.; Marconi, M.; Marcos Santos,
M. M. S.; Marinoni, S.; Marocco, F.; Marshall, D. J.; Martin Polo, L.;
Martín-Fleitas, J. M.; Masip, A.; Massari, D.; Mastrobuono-Battisti,
A.; Mazeh, T.; Messina, S.; Michalik, D.; Millar, N. R.; Mints, A.;
Molina, D.; Molinaro, R.; Molnár, L.; Montegriffo, P.; Mor, R.;
Morbidelli, R.; Morel, T.; Morris, D.; Mulone, A. F.; Munoz, D.;
Muraveva, T.; Murphy, C. P.; Musella, I.; Noval, L.; Ordénovic, C.;
Orrù, G.; Osinde, J.; Pagani, C.; Pagano, I.; Palaversa, L.; Palicio,
P. A.; Panahi, A.; Pawlak, M.; Peñalosa Esteller, X.; Penttilä, A.;
Piersimoni, A. M.; Pineau, F. -X.; Plachy, E.; Plum, G.; Poggio, E.;
Poretti, E.; Poujoulet, E.; Prša, A.; Pulone, L.; Racero, E.; Ragaini,
S.; Rainer, M.; Raiteri, C. M.; Rambaux, N.; Ramos, P.; Re Fiorentin,
P.; Regibo, S.; Reylé, C.; Ripepi, V.; Riva, A.; Rixon, G.; Robichon,
N.; Robin, C.; Roelens, M.; Rohrbasser, L.; Romero-Gómez, M.; Rowell,
N.; Royer, F.; Rybicki, K. A.; Sadowski, G.; Sagristà Sellés, A.;
Sahlmann, J.; Salgado, J.; Salguero, E.; Samaras, N.; Sanchez Gimenez,
V.; Sanna, N.; Santoveña, R.; Sarasso, M.; Schultheis, M.; Sciacca,
E.; Segol, M.; Segovia, J. C.; Ségransan, D.; Semeux, D.; Siddiqui,
H. I.; Siebert, A.; Siltala, L.; Slezak, E.; Smart, R. L.; Solano,
E.; Solitro, F.; Souami, D.; Souchay, J.; Spagna, A.; Spoto, F.;
Steele, I. A.; Süveges, M.; Szabados, L.; Szegedi-Elek, E.; Taris,
F.; Tauran, G.; Taylor, M. B.; Teixeira, R.; Thuillot, W.; Tonello, N.;
Torra, F.; Torra, J.; Turon, C.; Unger, N.; Vaillant, M.; van Dillen,
E.; Vanel, O.; Vecchiato, A.; Viala, Y.; Vicente, D.; Voutsinas, S.;
Weiler, M.; Wevers, T.; Wyrzykowski, Ł.; Yoldas, A.; Yvard, P.; Zhao,
H.; Zorec, J.; Zucker, S.; Zurbach, C.; Zwitter, T.
Bibcode: 2021A&A...649A...9G
Altcode: 2020arXiv201202036G
Context. Gaia Early Data Release 3 (Gaia EDR3) provides accurate
astrometry for about 1.6 million compact (QSO-like) extragalactic
sources, 1.2 million of which have the best-quality five-parameter
astrometric solutions.
Aims: The proper motions of QSO-like
sources are used to reveal a systematic pattern due to the acceleration
of the solar systembarycentre with respect to the rest frame of the
Universe. Apart from being an important scientific result by itself,
the acceleration measured in this way is a good quality indicator of the
Gaia astrometric solution.
Methods: Theeffect of the acceleration
was obtained as a part of the general expansion of the vector field of
proper motions in vector spherical harmonics (VSH). Various versions
of the VSH fit and various subsets of the sources were tried and
compared to get the most consistent result and a realistic estimate of
its uncertainty. Additional tests with the Gaia astrometric solution
were used to get a better idea of the possible systematic errors in the
estimate.
Results: Our best estimate of the acceleration based on
Gaia EDR3 is (2.32 ± 0.16) × 10−10 m s−2 (or
7.33 ±0.51 km s−1 Myr−1) towards α = 269.1° ± 5.4°,
δ = −31.6° ± 4.1°, corresponding to a proper motion amplitude
of 5.05 ±0.35 μas yr−1. This is in good agreement
with the acceleration expected from current models of the Galactic
gravitational potential. We expect that future Gaia data releases will
provide estimates of the acceleration with uncertainties substantially
below 0.1 μas yr−1. Movie is only available at https://www.aanda.org
Title: Gaia Early Data Release 3. The Gaia Catalogue of Nearby Stars
Authors: Gaia Collaboration; Smart, R. L.; Sarro, L. M.; Rybizki, J.;
Reylé, C.; Robin, A. C.; Hambly, N. C.; Abbas, U.; Barstow, M. A.;
de Bruijne, J. H. J.; Bucciarelli, B.; Carrasco, J. M.; Cooper, W. J.;
Hodgkin, S. T.; Masana, E.; Michalik, D.; Sahlmann, J.; Sozzetti, A.;
Brown, A. G. A.; Vallenari, A.; Prusti, T.; Babusiaux, C.; Biermann,
M.; Creevey, O. L.; Evans, D. W.; Eyer, L.; Hutton, A.; Jansen, F.;
Jordi, C.; Klioner, S. A.; Lammers, U.; Lindegren, L.; Luri, X.;
Mignard, F.; Panem, C.; Pourbaix, D.; Randich, S.; Sartoretti, P.;
Soubiran, C.; Walton, N. A.; Arenou, F.; Bailer-Jones, C. A. L.;
Bastian, U.; Cropper, M.; Drimmel, R.; Katz, D.; Lattanzi, M. G.;
van Leeuwen, F.; Bakker, J.; Castañeda, J.; De Angeli, F.; Ducourant,
C.; Fabricius, C.; Fouesneau, M.; Frémat, Y.; Guerra, R.; Guerrier,
A.; Guiraud, J.; Jean-Antoine Piccolo, A.; Messineo, R.; Mowlavi,
N.; Nicolas, C.; Nienartowicz, K.; Pailler, F.; Panuzzo, P.; Riclet,
F.; Roux, W.; Seabroke, G. M.; Sordo, R.; Tanga, P.; Thévenin, F.;
Gracia-Abril, G.; Portell, J.; Teyssier, D.; Altmann, M.; Andrae, R.;
Bellas-Velidis, I.; Benson, K.; Berthier, J.; Blomme, R.; Brugaletta,
E.; Burgess, P. W.; Busso, G.; Carry, B.; Cellino, A.; Cheek, N.;
Clementini, G.; Damerdji, Y.; Davidson, M.; Delchambre, L.; Dell'Oro,
A.; Fernández-Hernández, J.; Galluccio, L.; García-Lario, P.;
Garcia-Reinaldos, M.; González-Núñez, J.; Gosset, E.; Haigron,
R.; Halbwachs, J. -L.; Harrison, D. L.; Hatzidimitriou, D.; Heiter,
U.; Hernández, J.; Hestroffer, D.; Holl, B.; Janßen, K.; Jevardat
de Fombelle, G.; Jordan, S.; Krone-Martins, A.; Lanzafame, A. C.;
Löffler, W.; Lorca, A.; Manteiga, M.; Marchal, O.; Marrese, P. M.;
Moitinho, A.; Mora, A.; Muinonen, K.; Osborne, P.; Pancino, E.;
Pauwels, T.; Recio-Blanco, A.; Richards, P. J.; Riello, M.; Rimoldini,
L.; Roegiers, T.; Siopis, C.; Smith, M.; Ulla, A.; Utrilla, E.; van
Leeuwen, M.; van Reeven, W.; Abreu Aramburu, A.; Accart, S.; Aerts,
C.; Aguado, J. J.; Ajaj, M.; Altavilla, G.; Álvarez, M. A.; Álvarez
Cid-Fuentes, J.; Alves, J.; Anderson, R. I.; Anglada Varela, E.;
Antoja, T.; Audard, M.; Baines, D.; Baker, S. G.; Balaguer-Núñez,
L.; Balbinot, E.; Balog, Z.; Barache, C.; Barbato, D.; Barros, M.;
Bartolomé, S.; Bassilana, J. -L.; Bauchet, N.; Baudesson-Stella, A.;
Becciani, U.; Bellazzini, M.; Bernet, M.; Bertone, S.; Bianchi, L.;
Blanco-Cuaresma, S.; Boch, T.; Bombrun, A.; Bossini, D.; Bouquillon,
S.; Bragaglia, A.; Bramante, L.; Breedt, E.; Bressan, A.; Brouillet,
N.; Burlacu, A.; Busonero, D.; Butkevich, A. G.; Buzzi, R.; Caffau,
E.; Cancelliere, R.; Cánovas, H.; Cantat-Gaudin, T.; Carballo,
R.; Carlucci, T.; Carnerero, M. I.; Casamiquela, L.; Castellani, M.;
Castro-Ginard, A.; Castro Sampol, P.; Chaoul, L.; Charlot, P.; Chemin,
L.; Chiavassa, A.; Cioni, M. -R. L.; Comoretto, G.; Cornez, T.; Cowell,
S.; Crifo, F.; Crosta, M.; Crowley, C.; Dafonte, C.; Dapergolas, A.;
David, M.; David, P.; de Laverny, P.; De Luise, F.; De March, R.; De
Ridder, J.; de Souza, R.; de Teodoro, P.; de Torres, A.; del Peloso,
E. F.; del Pozo, E.; Delgado, A.; Delgado, H. E.; Delisle, J. -B.;
Di Matteo, P.; Diakite, S.; Diener, C.; Distefano, E.; Dolding,
C.; Eappachen, D.; Edvardsson, B.; Enke, H.; Esquej, P.; Fabre, C.;
Fabrizio, M.; Faigler, S.; Fedorets, G.; Fernique, P.; Fienga, A.;
Figueras, F.; Fouron, C.; Fragkoudi, F.; Fraile, E.; Franke, F.; Gai,
M.; Garabato, D.; Garcia-Gutierrez, A.; García-Torres, M.; Garofalo,
A.; Gavras, P.; Gerlach, E.; Geyer, R.; Giacobbe, P.; Gilmore, G.;
Girona, S.; Giuffrida, G.; Gomel, R.; Gomez, A.; Gonzalez-Santamaria,
I.; González-Vidal, J. J.; Granvik, M.; Gutiérrez-Sánchez, R.; Guy,
L. P.; Hauser, M.; Haywood, M.; Helmi, A.; Hidalgo, S. L.; Hilger,
T.; Hładczuk, N.; Hobbs, D.; Holland, G.; Huckle, H. E.; Jasniewicz,
G.; Jonker, P. G.; Juaristi Campillo, J.; Julbe, F.; Karbevska, L.;
Kervella, P.; Khanna, S.; Kochoska, A.; Kontizas, M.; Kordopatis, G.;
Korn, A. J.; Kostrzewa-Rutkowska, Z.; Kruszyńska, K.; Lambert, S.;
Lanza, A. F.; Lasne, Y.; Le Campion, J. -F.; Le Fustec, Y.; Lebreton,
Y.; Lebzelter, T.; Leccia, S.; Leclerc, N.; Lecoeur-Taibi, I.; Liao,
S.; Licata, E.; Lindstrøm, H. E. P.; Lister, T. A.; Livanou, E.;
Lobel, A.; Madrero Pardo, P.; Managau, S.; Mann, R. G.; Marchant,
J. M.; Marconi, M.; Marcos Santos, M. M. S.; Marinoni, S.; Marocco,
F.; Marshall, D. J.; Martin Polo, L.; Martín-Fleitas, J. M.; Masip,
A.; Massari, D.; Mastrobuono-Battisti, A.; Mazeh, T.; McMillan,
P. J.; Messina, S.; Millar, N. R.; Mints, A.; Molina, D.; Molinaro,
R.; Molnár, L.; Montegriffo, P.; Mor, R.; Morbidelli, R.; Morel,
T.; Morris, D.; Mulone, A. F.; Munoz, D.; Muraveva, T.; Murphy,
C. P.; Musella, I.; Noval, L.; Ordénovic, C.; Orrù, G.; Osinde,
J.; Pagani, C.; Pagano, I.; Palaversa, L.; Palicio, P. A.; Panahi,
A.; Pawlak, M.; Peñalosa Esteller, X.; Penttilä, A.; Piersimoni,
A. M.; Pineau, F. -X.; Plachy, E.; Plum, G.; Poggio, E.; Poretti,
E.; Poujoulet, E.; Prša, A.; Pulone, L.; Racero, E.; Ragaini, S.;
Rainer, M.; Raiteri, C. M.; Rambaux, N.; Ramos, P.; Ramos-Lerate,
M.; Re Fiorentin, P.; Regibo, S.; Ripepi, V.; Riva, A.; Rixon, G.;
Robichon, N.; Robin, C.; Roelens, M.; Rohrbasser, L.; Romero-Gómez,
M.; Rowell, N.; Royer, F.; Rybicki, K. A.; Sadowski, G.; Sagristà
Sellés, A.; Salgado, J.; Salguero, E.; Samaras, N.; Sanchez Gimenez,
V.; Sanna, N.; Santoveña, R.; Sarasso, M.; Schultheis, M.; Sciacca,
E.; Segol, M.; Segovia, J. C.; Ségransan, D.; Semeux, D.; Shahaf,
S.; Siddiqui, H. I.; Siebert, A.; Siltala, L.; Slezak, E.; Solano, E.;
Solitro, F.; Souami, D.; Souchay, J.; Spagna, A.; Spoto, F.; Steele,
I. A.; Steidelmüller, H.; Stephenson, C. A.; Süveges, M.; Szabados,
L.; Szegedi-Elek, E.; Taris, F.; Tauran, G.; Taylor, M. B.; Teixeira,
R.; Thuillot, W.; Tonello, N.; Torra, F.; Torra, J.; Turon, C.; Unger,
N.; Vaillant, M.; van Dillen, E.; Vanel, O.; Vecchiato, A.; Viala, Y.;
Vicente, D.; Voutsinas, S.; Weiler, M.; Wevers, T.; Wyrzykowski, Ł.;
Yoldas, A.; Yvard, P.; Zhao, H.; Zorec, J.; Zucker, S.; Zurbach, C.;
Zwitter, T.
Bibcode: 2021A&A...649A...6G
Altcode: 2020arXiv201202061G
Aims: We produce a clean and well-characterised catalogue of
objects within 100 pc of the Sun from the Gaia Early Data Release 3. We
characterise the catalogue through comparisons to the full data release,
external catalogues, and simulations. We carry out a first analysis
of the science that is possible with this sample to demonstrate its
potential and best practices for its use.
Methods: Theselection
of objects within 100 pc from the full catalogue used selected training
sets, machine-learning procedures, astrometric quantities, and solution
quality indicators to determine a probability that the astrometric
solution is reliable. The training set construction exploited the
astrometric data, quality flags, and external photometry. For all
candidates we calculated distance posterior probability densities
using Bayesian procedures and mock catalogues to define priors. Any
object with reliable astrometry and a non-zero probability of being
within 100 pc is included in the catalogue.
Results: We have
produced a catalogue of 331 312 objects that we estimate contains at
least 92% of stars of stellar type M9 within 100 pc of the Sun. We
estimate that 9% of the stars in this catalogue probably lie outside
100 pc, but when the distance probability function is used, a correct
treatment of this contamination is possible. We produced luminosity
functions with a high signal-to-noise ratio for the main-sequence
stars, giants, and white dwarfs. We examined in detail the Hyades
cluster, the white dwarf population, and wide-binary systems and
produced candidate lists for all three samples. We detected local
manifestations of several streams, superclusters, and halo objects,
in which we identified 12 members of Gaia Enceladus. We present the
first direct parallaxes of five objects in multiple systems within
10 pc of the Sun.
Conclusions: We provide the community
with a large, well-characterised catalogue of objects in the
solar neighbourhood. This is a primary benchmark for measuring and
understanding fundamental parameters and descriptive functions in
astronomy. Tables are only available at the CDS via anonymous ftp
to cdsarc.u-strasbg.fr
(ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/cat/J/A+A/649/A6
Title: VizieR Online Data Catalog: Gaia white dwarfs within 40pc. I
(Tremblay+, 2020)
Authors: Tremblay, P. -E.; Hollands, M. A.; Gentile Fusillo, N. P.;
McCleery, J.; Izquierdo, P.; Gansicke, B. T.; Cukanovaite, E.;
Koester, D.; Brown, W. R.; Charpinet, S.; Cunningham, T.; Farihi,
J.; Giammichele, N.; Van Grootel, V.; Hermes, J. J.; Hoskin, M. J.;
Jordan, S.; Kepler, S. O.; Kleinman, S. J.; Manser, C. J.; Marsh,
T. R.; de Martino, D.; Nitta, A.; Parsons, S. G.; Pelisoli, I.; Raddi,
R.; Rebassa-Mansergas, A.; Ren, J. -J.; Schreiber, M. R.; Silvotti,
R.; Toloza, O.; Toonen, S.; Torres, S.
Bibcode: 2021yCat..74970130T
Altcode:
We selected white dwarf candidates from the catalogue of Gentile
Fusillo et al. (2019MNRAS.482.4570G, cat. J/MNRAS/482/4570)
with Plx>25mas+/-1σ as the only requirement, resulting in
1233 sources, among which 184 are low probability candidates
(PWD<0.75). We observed a total of 230 white dwarf
candidates at the Observatorio del Roque de los Muchachos, both with
the Intermediate-dispersion Spectrograph and Imaging System (ISIS)
on the WHT and the Optical System for Imaging and low-Resolution
Integrated Spectroscopy (OSIRIS) on the GTC. (1 data file).
Title: VizieR Online Data Catalog: MC structure and properties
(Gaia Collaboration+, 2021)
Authors: Gaia Collaboration; Luri, X.; Chemin, L.; Clementini,
G.; Delgado, H. E.; McMillan, P. J.; Romero-Gomez, M.; Balbinot,
E.; Castro-Ginard, A.; Mor, R.; Ripepi, V.; Sarro, L. M.; Cioni,
M. -R. L.; Fabricius, C.; Garofalo, A.; Helmi, A.; Muraveva, T.;
Brown, A. G. A.; Vallenari, A.; Prusti, T.; de Bruijne, J. H. J.;
Babusiaux, C.; Biermann, M.; Creevey, O. L.; Evans, D. W.; Eyer,
L.; Hutton, A.; Jansen, F.; Jordi, C.; Klioner, S. A.; Lammers, U.;
Lindegren, L.; Mignard, F.; Panem, C.; Pourbaix, D.; Randich, S.;
Sartoretti, P.; Soubiran, C.; Walton, N. A.; Arenou, F.; Bailer-Jones,
C. A. L.; Bastian, U.; Cropper, M.; Drimmel, R.; Katz, D.; Lattanzi,
M. G.; van Leeuwen, F.; Bakker, J.; Castaneda, J.; de Angeli, F.;
Ducourant, C.; Fouesneau, M.; Fremat, Y.; Guerra, R.; Guerrier, A.;
Guiraud, J.; Jean-Antoine Piccolo, A.; Masana, E.; Messineo, R.;
Mowlavi, N.; Nicolas, C.; Nienartowicz, K.; Pailler, F.; Panuzzo,
P.; Riclet, F.; Roux, W.; Seabroke, G. M.; Sordo, R.; Tanga, P.;
Thevenin, F.; Gracia-Abril, G.; Portell, J.; Teyssier, D.; Altmann,
M.; Andrae, R.; Bellas-Velidis, I.; Benson, K.; Berthier, J.;
Blomme, R.; Brugaletta, E.; Burgess, P. W.; Busso, G.; Carry, B.;
Cellino, A.; Cheek, N.; Damerdji, Y.; Davidson, M.; Delchambre, L.;
Dell'Oro, A.; Fernandez-Hernandez, J.; Galluccio, L.; Garcia-Lario,
P.; Garcia-Reinaldos, M.; Gonzalez-Nunez, J.; Gosset, E.; Haigron,
R.; Halbwachs, J. -L.; Hambly, N. C.; Harrison, D. L.; Hatzidimitriou,
D.; Heiter, U.; Hernandez, J.; Hestroffer, D.; Hodgkin, S. T.; Holl,
B.; Janssen, K.; Jevardat de Fombelle, G.; Jordan, S.; Krone-Martins,
A.; Lanzafame, A. C.; Loeffler, W.; Lorca, A.; Manteiga, M.; Marchal,
O.; Marrese, P. M.; Moitinho, A.; Mora, A.; Muinonen, K.; Osborne, P.;
Pancino, E.; Pauwels, T.; Recio-Blanco, A.; Richards, P. J.; Riello,
M.; Rimoldini, L.; Robin, A. C.; Roegiers, T.; Rybizki, J.; Siopis,
C.; Smith, M.; Sozzetti, A.; Ulla, A.; Utrilla, E.; van Leeuwen, M.;
van Reeven, W.; Abbas, U.; Abreu Aramburu, A.; Accart, S.; Aerts,
C.; Aguado, J. J.; Ajaj, M.; Altavilla, G.; Alvarez, M. A.; Alvarez
Cid-Fuentes, J.; Alves, J.; Anderson, R. I.; Anglada Varela, E.;
Antoja, T.; Audard, M.; Baines, D.; Baker, S. G.; Balaguer-Nunez,
L.; Balog, Z.; Barache, C.; Barbato, D.; Barros, M.; Barstow, M. A.;
Bartolome, S.; Bassilana, J. -L.; Bauchet, N.; Baudesson-Stella, A.;
Becciani, U.; Bellazzini, M.; Bernet, M.; Bertone, S.; Bianchi, L.;
Blanco-Cuaresma, S.; Boch, T.; Bombrun, A.; Bossini, D.; Bouquillon,
S.; Bragaglia, A.; Bramante, L.; Breedt, E.; Bressan, A.; Brouillet,
N.; Bucciarelli, B.; Burlacu, A.; Busonero, D.; Butkevich, A. G.;
Buzzi, R.; Caffau, E.; Cancelliere, R.; Canovas, H.; Cantat-Gaudin,
T.; Carballo, R.; Carlucci, T.; Carnerero, M. I.; Carrasco, J. M.;
Casamiquela, L.; Castellani, M.; Castro Sampol, P.; Chaoul, L.;
Charlot, P.; Chiavassa, A.; Comoretto, G.; Cooper, W. J.; Cornez,
T.; Cowell, S.; Crifo, F.; Crosta, M.; Crowley, C.; Dafonte, C.;
Dapergolas, A.; David, M.; David, P.; de Laverny, P.; de Luise, F.;
de March, R.; De Ridder, J.; de Souza, R.; de Teodoro, P.; de Torres,
A.; Del Peloso, E. F.; Del Pozo, E.; Delgado, A.; Delisle, J. -B.;
Di Matteo, P.; Diakite, S.; Diener, C.; Distefano, E.; Dolding,
C.; Eappachen, D.; Enke, H.; Esquej, P.; Fabre, C.; Fabrizio, M.;
Faigler, S.; Fedorets, G.; Fernique, P.; Fienga, A.; Figueras, F.;
Fouron, C.; Fragkoudi, F.; Fraile, E.; Franke, F.; Gai, M.; Garabato,
D.; Garcia-Gutierrez, A.; Garcia-Torres, M.; Gavras, P.; Gerlach,
E.; Geyer, R.; Giacobbe, P.; Gilmore, G.; Girona, S.; Giuffrida, G.;
Gomez, A.; Gonzalez-Santamaria, I.; Gonzalez-Vidal, J. J.; Granvik,
M.; Gutierrez-Sanchez, R.; Guy, L. P.; Hauser, M.; Haywood, M.;
Hidalgo, S. L.; Hilger, T.; Hladczuk, N.; Hobbs, D.; Holland, G.;
Huckle, H. E.; Jasniewicz, G.; Jonker, P. G.; Juaristi Campillo, J.;
Julbe, F.; Karbevska, L.; Kervella, P.; Khanna, S.; Kochoska, A.;
Kontizas, M.; Kordopatis, G.; Korn, A. J.; Kostrzewa-Rutkowska, Z.;
Kruszynska, K.; Lambert, S.; Lanza, A. F.; Lasne, Y.; Le Campion,
J. -F.; Le Fustec, Y.; Lebreton, Y.; Lebzelter, T.; Leccia, S.;
Leclerc, N.; Lecoeur-Taibi, I.; Liao, S.; Licata, E.; Lindstrom,
H. E. P.; Lister, T. A.; Livanou, E.; Lobel, A.; Madrero Pardo, P.;
Managau, S.; Mann, R. G.; Marchant, J. M.; Marconi, M.; Marcos Santos,
M. M. S.; Marinoni, S.; Marocco, F.; Marshall, D. J.; Martin Polo, L.;
Martin-Fleitas, J. M.; Masip, A.; Massari, D.; Mastrobuono-Battisti,
A.; Mazeh, T.; Messina, S.; Michalik, D.; Millar, N. R.; Mints, A.;
Molina, D.; Molinaro, R.; Molnar, L.; Montegriffo, P.; Morbidelli,
R.; Morel, T.; Morris, D.; Mulone, A. F.; Munoz, D.; Murphy, C. P.;
Musella, I.; Noval, L.; Ordenovic, C.; Orru, G.; Osinde, J.; Pagani,
C.; Pagano, I.; Palaversa, L.; Palicio, P. A.; Panahi, A.; Pawlak,
M.; Penalosa Esteller, X.; Penttilae, A.; Piersimoni, A. M.; Pineau,
F. -X.; Plachy, E.; Plum, G.; Poggio, E.; Poretti, E.; Poujoulet, E.;
Prsa, A.; Pulone, L.; Racero, E.; Ragaini, S.; Rainer, M.; Raiteri,
C. M.; Rambaux, N.; Ramos, P.; Ramos-Lerate, M.; Re Fiorentin, P.;
Regibo, S.; Reyle, C.; Riva, A.; Rixon, G.; Robichon, N.; Robin, C.;
Roelens, M.; Rohrbasser, L.; Rowell, N.; Royer, F.; Rybicki, K. A.;
Sadowski, G.; Sagrista Selles, A.; Sahlmann, J.; Salgado, J.; Salguero,
E.; Samaras, N.; Sanchez Gimenez, V.; Sanna, N.; Santovena, R.;
Sarasso, M.; Schultheis, M.; Sciacca, E.; Segol, M.; Segovia, J. C.;
Segransan, D.; Semeux, D.; Siddiqui, H. I.; Siebert, A.; Siltala,
L.; Slezak, E.; Smart, R. L.; Solano, E.; Solitro, F.; Souami, D.;
Souchay, J.; Spagna, A.; Spoto, F.; Steele, I. A.; Steidelmueller,
H.; Stephenson, C. A.; Sueveges, M.; Szabados, L.; Szegedi-Elek, E.;
Taris, F.; Tauran, G.; Taylor, M. B.; Teixeira, R.; Thuillot, W.;
Tonello, N.; Torra, F.; Torra, J.; Turon, C.; Unger, N.; Vaillant,
M.; van Dillen, E.; Vanel, O.; Vecchiato, A.; Viala, Y.; Vicente,
D.; Voutsinas, S.; Weiler, M.; Wevers, T.; Wyrzykowski, L.; Yoldas, A.;
Yvard, P.; Zhao, H.; Zorec, J.; Zucker, S.; Zurbach, C.; Zwitter, T.
Bibcode: 2020yCat..36490007G
Altcode:
Tables of the radial profiles of the azimuthal and radial components
of the ordered and random motions of stellar evolutionary phases in
the Large Magellanic Cloud, as inferred from the 3rd Gaia Data Release
(Early Release of 2020/12/03). Each sub-sample of LMC stellar
evolutionary phase is defined in Sect. 2.3 of the article. The file
lmcall.dat is for a sample combining every stellar phases. (9
data files).
Title: VizieR Online Data Catalog: Gaia Catalogue of Nearby Stars -
GCNS (Gaia collaboration, 2021)
Authors: Gaia Collaboration; Smart, R. L.; Sarro, L. M.; Rybizki,
J.; Reyle, C.; Robin, A. C.; Hambly, N. C.; Abbas, U.; Barstow,
M. A.; de Bruijne, J. H. J.; Bucciarelli, B.; Carrasco, J. M.;
Cooper, W. J.; Hodgkin, S. T.; Masana, E.; Michalik, D.; Sahlmann,
J.; Sozzetti, A.; Brown, A. G. A.; Vallenari, A.; Prusti, T.;
Babusiaux, C.; Biermann, M.; Creevey, O. L.; Evans, D. W.; Eyer,
L.; Hutton, A.; Jansen, F.; Jordi, C.; Klioner, S. A.; Lammers,
U.; Lindegren, L.; Luri, X.; Mignard, F.; Panem, C.; Pourbaix, D.;
Randich, S.; Sartoretti, P.; Soubiran, C.; Walton, N. A.; Arenou,
F.; Bailer-Jones, C. A. L.; Bastian, U.; Cropper, M.; Drimmel, R.;
Katz, D.; Lattanzi, M. G.; van Leeuwen, F.; Bakker, J.; Castaneda, J.;
de Angeli, F.; Ducourant, C.; Fabricius, C.; Fouesneau, M.; Fremat,
Y.; Guerra, R.; Guerrier, A.; Guiraud, J.; Jean-Antoine Piccolo, A.;
Messineo, R.; Mowlavi, N.; Nicolas, C.; Nienartowicz, K.; Pailler,
F.; Panuzzo, P.; Riclet, F.; Roux, W.; Seabroke, G. M.; Sordo, R.;
Tanga, P.; Thevenin, F.; Gracia-Abril, G.; Portell, J.; Teyssier, D.;
Altmann, M.; Andrae, R.; Bellas-Velidis, I.; Benson, K.; Berthier,
J.; Blomme, R.; Brugaletta, E.; Burgess, P. W.; Busso, G.; Carry, B.;
Cellino, A.; Cheek, N.; Clementini, G.; Damerdji, Y.; Davidson, M.;
Delchambre, L.; Dell'Oro, A.; Fernandez-Hernandez, J.; Galluccio, L.;
Garcia-Lario, P.; Garcia-Reinaldos, M.; Gonzalez-Nunez, J.; Gosset,
E.; Haigron, R.; Halbwachs, J. -L.; Harrison, D. L.; Hatzidimitriou,
D.; Heiter, U.; Hernandez, J.; Hestroffer, D.; Holl, B.; Janssen, K.;
Jevardat de Fombelle, G.; Jordan, S.; Krone-Martins, A.; Lanzafame,
A. C.; Loeffler, W.; Lorca, A.; Manteiga, M.; Marchal, O.; Marrese,
P. M.; Moitinho, A.; Mora, A.; Muinonen, K.; Osborne, P.; Pancino,
E.; Pauwels, T.; Recio-Blanco, A.; Richards, P. J.; Riello, M.;
Rimoldini, L.; Roegiers, T.; Siopis, C.; Smith, M.; Ulla, A.; Utrilla,
E.; van Leeuwen, M.; van Reeven, W.; Abreu Aramburu, A.; Accart, S.;
Aerts, C.; Aguado, J. J.; Ajaj, M.; Altavilla, G.; Alvarez, M. A.;
Alvarez Cid-Fuentes, J.; Alves, J.; Anderson, R. I.; Anglada Varela,
E.; Antoja, T.; Audard, M.; Baines, D.; Baker, S. G.; Balaguer-Nunez,
L.; Balbinot, E.; Balog, Z.; Barache, C.; Barbato, D.; Barros, M.;
Bartolome, S.; Bassilana, J. -L.; Bauchet, N.; Baudesson-Stella, A.;
Becciani, U.; Bellazzini, M.; Bernet, M.; Bertone, S.; Bianchi, L.;
Blanco-Cuaresma, S.; Boch, T.; Bombrun, A.; Bossini, D.; Bouquillon,
S.; Bragaglia, A.; Bramante, L.; Breedt, E.; Bressan, A.; Brouillet,
N.; Burlacu, A.; Busonero, D.; Butkevich, A. G.; Buzzi, R.; Caffau,
E.; Cancelliere, R.; Canovas, H.; Cantat-Gaudin, T.; Carballo, R.;
Carlucci, T.; Carnerero, M. I.
Bibcode: 2020yCat..36490006G
Altcode:
We produce a clean and well characterised catalogue of nearby
objects within 100pc of the Sun from the Gaia early third data
release. We characterise the catalogue using the full data release,
and comparisons to other catalogues in literature and simulations. We
started with a sample of objects with a measured parallax of 8mas. For
all candidates we calculate a distance probability function using
Bayesian procedures and mock catalogues for the prediction of the
priors. For each entry using a random forest classifier we attempt
to remove sources with spurious astrometric solutions. >From
this paper we provide the following data files: table1c.dat
(Table1GCNScat): Any object with a non-zero probability
of being within 100 pc and not indicated as a spurious astrometric
solutions. We have also included external photometric and radial
velocity data, the probability of reliable astrometry, probability to
be a white dwarf, the distance 1st, 16th, 50th and 84th percentiles,
the positions and velocities in a galactic reference frame. For
questions please email richard.smart(at)inaf.it. table1r.dat
(Table1GCNSreject): All other entries from the 8mas
sample that were rejected as having a zero probability of being
inside 100pc or indicated as a spurious astrometric solution. This
table has the same format and columns as GCNS_cat.dat. progwd.dat
(ProbWDlt05_ProbGFgt05): A catalogue of 45 sources with low probability
of being a WD in this work (PWD<0.5), but having larger probabilities
in Gentile-Fusillo et al (2019MNRAS.482.4570G, cat. J/MNRAS/482/4570)
(PGF>0.5). For questions please email carrasco(at)fqa.ub.edu. table3.dat (Table3_ResolvedStellarSystems): Resolved binary
candidates in the GCNS catalogue as discussed in the section on
stellar multiplicity: resolved systems. For questions please email
ummi.abbas(at)inaf.it or alessandro.sozzetti(at)inaf.it. maglim.dat
(maglimhpx5percentile): The magnitude percentiles for level
5 healpixels used in the luminosity function determinations. For
questions please email rybizki(at)mpia.de. distpdf.dat
(distance_PDF): The full distance probability density function
calculated in section 2 and used throughout the paper. For questions
please email rybizki(at)mpia.de. missing.dat (missing_10mas):
A list of 1258 objects with published parallaxes greater than 10mas
that are not or have no parallax in EDR3. For questions please email
celine.reyle(at)obs-besancon.fr. hyacomb.dat (Hyades_ComaBer):
A list of 920+212 probable Hyades and ComaBer members in the GCNS
sample. For questions please email daniel.michalik(at)esa.int or
jos.de.bruijne(at)esa.int. (8 data files).
Title: Gaia Data Release 2. The kinematics of globular clusters and
dwarf galaxies around the Milky Way (Corrigendum)
Authors: Gaia Collaboration; Helmi, A.; van Leeuwen, F.; McMillan,
P. J.; Massari, D.; Antoja, T.; Robin, A. C.; Lindegren, L.;
Bastian, U.; Arenou, F.; Babusiaux, C.; Biermann, M.; Breddels,
M. A.; Hobbs, D.; Jordi, C.; Pancino, E.; Reylé, C.; Veljanoski,
J.; Brown, A. G. A.; Vallenari, A.; Prusti, T.; de Bruijne,
J. H. J.; Bailer-Jones, C. A. L.; Evans, D. W.; Eyer, L.; Jansen,
F.; Klioner, S. A.; Lammers, U.; Luri, X.; Mignard, F.; Panem,
C.; Pourbaix, D.; Randich, S.; Sartoretti, P.; Siddiqui, H. I.;
Soubiran, C.; Walton, N. A.; Cropper, M.; Drimmel, R.; Katz, D.;
Lattanzi, M. G.; Bakker, J.; Cacciari, C.; Castañeda, J.; Chaoul,
L.; Cheek, N.; De Angeli, F.; Fabricius, C.; Guerra, R.; Holl, B.;
Masana, E.; Messineo, R.; Mowlavi, N.; Nienartowicz, K.; Panuzzo,
P.; Portell, J.; Riello, M.; Seabroke, G. M.; Tanga, P.; Thévenin,
F.; Gracia-Abril, G.; Comoretto, G.; Garcia-Reinaldos, M.; Teyssier,
D.; Altmann, M.; Andrae, R.; Audard, M.; Bellas-Velidis, I.; Benson,
K.; Berthier, J.; Blomme, R.; Burgess, P.; Busso, G.; Carry, B.;
Cellino, A.; Clementini, G.; Clotet, M.; Creevey, O.; Davidson,
M.; De Ridder, J.; Delchambre, L.; Dell'Oro, A.; Ducourant, C.;
Fernández-Hernández, J.; Fouesneau, M.; Frémat, Y.; Galluccio, L.;
García-Torres, M.; González-Núñez, J.; González-Vidal, J. J.;
Gosset, E.; Guy, L. P.; Halbwachs, J. -L.; Hambly, N. C.; Harrison,
D. L.; Hernández, J.; Hestroffer, D.; Hodgkin, S. T.; Hutton, A.;
Jasniewicz, G.; Jean-Antoine-Piccolo, A.; Jordan, S.; Korn, A. J.;
Krone-Martins, A.; Lanzafame, A. C.; Lebzelter, T.; Löffler, W.;
Manteiga, M.; Marrese, P. M.; Martín-Fleitas, J. M.; Moitinho, A.;
Mora, A.; Muinonen, K.; Osinde, J.; Pauwels, T.; Petit, J. -M.;
Recio-Blanco, A.; Richards, P. J.; Rimoldini, L.; Sarro, L. M.;
Siopis, C.; Smith, M.; Sozzetti, A.; Süveges, M.; Torra, J.; van
Reeven, W.; Abbas, U.; Abreu Aramburu, A.; Accart, S.; Aerts, C.;
Altavilla, G.; Álvarez, M. A.; Alvarez, R.; Alves, J.; Anderson,
R. I.; Andrei, A. H.; Anglada Varela, E.; Antiche, E.; Arcay, B.;
Astraatmadja, T. L.; Bach, N.; Baker, S. G.; Balaguer-Núñez, L.;
Balm, P.; Barache, C.; Barata, C.; Barbato, D.; Barblan, F.; Barklem,
P. S.; Barrado, D.; Barros, M.; Barstow, M. A.; Bartholomé Muñoz,
S.; Bassilana, J. -L.; Becciani, U.; Bellazzini, M.; Berihuete, A.;
Bertone, S.; Bianchi, L.; Bienaymé, O.; Blanco-Cuaresma, S.; Boch,
T.; Boeche, C.; Bombrun, A.; Borrachero, R.; Bossini, D.; Bouquillon,
S.; Bourda, G.; Bragaglia, A.; Bramante, L.; Bressan, A.; Brouillet,
N.; Brüsemeister, T.; Brugaletta, E.; Bucciarelli, B.; Burlacu, A.;
Busonero, D.; Butkevich, A. G.; Buzzi, R.; Caffau, E.; Cancelliere,
R.; Cannizzaro, G.; Cantat-Gaudin, T.; Carballo, R.; Carlucci, T.;
Carrasco, J. M.; Casamiquela, L.; Castellani, M.; Castro-Ginard, A.;
Charlot, P.; Chemin, L.; Chiavassa, A.; Cocozza, G.; Costigan, G.;
Cowell, S.; Crifo, F.; Crosta, M.; Crowley, C.; Cuypers, J.; Dafonte,
C.; Damerdji, Y.; Dapergolas, A.; David, P.; David, M.; de Laverny,
P.; De Luise, F.; De March, R.; de Martino, D.; de Souza, R.; de
Torres, A.; Debosscher, J.; del Pozo, E.; Delbo, M.; Delgado, A.;
Delgado, H. E.; Di Matteo, P.; Diakite, S.; Diener, C.; Distefano,
E.; Dolding, C.; Drazinos, P.; Durán, J.; Edvardsson, B.; Enke, H.;
Eriksson, K.; Esquej, P.; Eynard Bontemps, G.; Fabre, C.; Fabrizio,
M.; Faigler, S.; Falcão, A. J.; Farràs Casas, M.; Federici, L.;
Fedorets, G.; Fernique, P.; Figueras, F.; Filippi, F.; Findeisen, K.;
Fonti, A.; Fraile, E.; Fraser, M.; Frézouls, B.; Gai, M.; Galleti,
S.; Garabato, D.; García-Sedano, F.; Garofalo, A.; Garralda, N.;
Gavel, A.; Gavras, P.; Gerssen, J.; Geyer, R.; Giacobbe, P.; Gilmore,
G.; Girona, S.; Giuffrida, G.; Glass, F.; Gomes, M.; Granvik, M.;
Gueguen, A.; Guerrier, A.; Guiraud, J.; Gutiérrez-Sánchez, R.;
Haigron, R.; Hatzidimitriou, D.; Hauser, M.; Haywood, M.; Heiter,
U.; Heu, J.; Hilger, T.; Hofmann, W.; Holland, G.; Huckle, H. E.;
Hypki, A.; Icardi, V.; Janßen, K.; Jevardat de Fombelle, G.; Jonker,
P. G.; Juhász, Á. L.; Julbe, F.; Karampelas, A.; Kewley, A.; Klar,
J.; Kochoska, A.; Kohley, R.; Kolenberg, K.; Kontizas, M.; Kontizas,
E.; Koposov, S. E.; Kordopatis, G.; Kostrzewa-Rutkowska, Z.; Koubsky,
P.; Lambert, S.; Lanza, A. F.; Lasne, Y.; Lavigne, J. -B.; Le Fustec,
Y.; Le Poncin-Lafitte, C.; Lebreton, Y.; Leccia, S.; Leclerc, N.;
Lecoeur-Taibi, I.; Lenhardt, H.; Leroux, F.; Liao, S.; Licata, E.;
Lindstrøm, H. E. P.; Lister, T. A.; Livanou, E.; Lobel, A.; López,
M.; Managau, S.; Mann, R. G.; Mantelet, G.; Marchal, O.; Marchant,
J. M.; Marconi, M.; Marinoni, S.; Marschalkó, G.; Marshall, D. J.;
Martino, M.; Marton, G.; Mary, N.; Matijevič, G.; Mazeh, T.; Messina,
S.; Michalik, D.; Millar, N. R.; Molina, D.; Molinaro, R.; Molnár,
L.; Montegriffo, P.; Mor, R.; Morbidelli, R.; Morel, T.; Morris, D.;
Mulone, A. F.; Muraveva, T.; Musella, I.; Nelemans, G.; Nicastro,
L.; Noval, L.; O'Mullane, W.; Ordénovic, C.; Ordóñez-Blanco,
D.; Osborne, P.; Pagani, C.; Pagano, I.; Pailler, F.; Palacin, H.;
Palaversa, L.; Panahi, A.; Pawlak, M.; Piersimoni, A. M.; Pineau,
F. -X.; Plachy, E.; Plum, G.; Poggio, E.; Poujoulet, E.; Prša, A.;
Pulone, L.; Racero, E.; Ragaini, S.; Rambaux, N.; Ramos-Lerate, M.;
Regibo, S.; Riclet, F.; Ripepi, V.; Riva, A.; Rivard, A.; Rixon, G.;
Roegiers, T.; Roelens, M.; Romero-Gómez, M.; Rowell, N.; Royer,
F.; Ruiz-Dern, L.; Sadowski, G.; Sagristà Sellés, T.; Sahlmann,
J.; Salgado, J.; Salguero, E.; Sanna, N.; Santana-Ros, T.; Sarasso,
M.; Savietto, H.; Schultheis, M.; Sciacca, E.; Segol, M.; Segovia,
J. C.; Ségransan, D.; Shih, I. -C.; Siltala, L.; Silva, A. F.; Smart,
R. L.; Smith, K. W.; Solano, E.; Solitro, F.; Sordo, R.; Soria Nieto,
S.; Souchay, J.; Spagna, A.; Spoto, F.; Stampa, U.; Steele, I. A.;
Steidelmüller, H.; Stephenson, C. A.; Stoev, H.; Suess, F. F.; Surdej,
J.; Szabados, L.; Szegedi-Elek, E.; Tapiador, D.; Taris, F.; Tauran,
G.; Taylor, M. B.; Teixeira, R.; Terrett, D.; Teyssandier, P.;
Thuillot, W.; Titarenko, A.; Torra Clotet, F.; Turon, C.; Ulla, A.;
Utrilla, E.; Uzzi, S.; Vaillant, M.; Valentini, G.; Valette, V.;
van Elteren, A.; Van Hemelryck, E.; van Leeuwen, M.; Vaschetto, M.;
Vecchiato, A.; Viala, Y.; Vicente, D.; Vogt, S.; von Essen, C.; Voss,
H.; Votruba, V.; Voutsinas, S.; Walmsley, G.; Weiler, M.; Wertz, O.;
Wevers, T.; Wyrzykowski, Ł.; Yoldas, A.; Žerjal, M.; Ziaeepour,
H.; Zorec, J.; Zschocke, S.; Zucker, S.; Zurbach, C.; Zwitter, T.
Bibcode: 2020A&A...642C...1G
Altcode:
No abstract at ADS
Title: Gaia white dwarfs within 40 pc - I. Spectroscopic observations
of new candidates
Authors: Tremblay, P. -E.; Hollands, M. A.; Gentile Fusillo, N. P.;
McCleery, J.; Izquierdo, P.; Gänsicke, B. T.; Cukanovaite, E.;
Koester, D.; Brown, W. R.; Charpinet, S.; Cunningham, T.; Farihi,
J.; Giammichele, N.; van Grootel, V.; Hermes, J. J.; Hoskin, M. J.;
Jordan, S.; Kepler, S. O.; Kleinman, S. J.; Manser, C. J.; Marsh,
T. R.; de Martino, D.; Nitta, A.; Parsons, S. G.; Pelisoli, I.; Raddi,
R.; Rebassa-Mansergas, A.; Ren, J. -J.; Schreiber, M. R.; Silvotti,
R.; Toloza, O.; Toonen, S.; Torres, S.
Bibcode: 2020MNRAS.497..130T
Altcode: 2020MNRAS.tmp.2021T; 2020arXiv200600965T
We present a spectroscopic survey of 230 white dwarf candidates
within 40 pc of the Sun from the William Herschel Telescope and Gran
Telescopio Canarias. All candidates were selected from Gaia Data
Release 2 (DR2) and in almost all cases, had no prior spectroscopic
classifications. We find a total of 191 confirmed white dwarfs and
39 main-sequence star contaminants. The majority of stellar remnants
in the sample are relatively cool (<Teff> = 6200
K), showing either hydrogen Balmer lines or a featureless spectrum,
corresponding to 89 DA and 76 DC white dwarfs, respectively. We also
recover two DBA white dwarfs and 9-10 magnetic remnants. We find
two carbon-bearing DQ stars and 14 new metal-rich white dwarfs. This
includes the possible detection of the first ultra-cool white dwarf
with metal lines. We describe three DZ stars for which we find at
least four different metal species, including one that is strongly
Fe- and Ni-rich, indicative of the accretion of a planetesimal with
core-Earth composition. We find one extremely massive (1.31 ± 0.01
M⊙) DA white dwarf showing weak Balmer lines, possibly
indicating stellar magnetism. Another white dwarf shows strong Balmer
line emission but no infrared excess, suggesting a low-mass sub-stellar
companion. A high spectroscopic completeness (>99 per cent) has now
been reached for Gaia DR2 sources within 40-pc sample, in the Northern
hemisphere (δ > 0°) and located on the white dwarf cooling track
in the Hertzsprung-Russell diagram. A statistical study of the full
northern sample is presented in a companion paper.
Title: Gaia Data Release 2. Kinematics of globular clusters and
dwarf galaxies around the Milky Way (Corrigendum)
Authors: Gaia Collaboration; Helmi, A.; van Leeuwen, F.; McMillan,
P. J.; Massari, D.; Antoja, T.; Robin, A. C.; Lindegren, L.;
Bastian, U.; Arenou, F.; Babusiaux, C.; Biermann, M.; Breddels,
M. A.; Hobbs, D.; Jordi, C.; Pancino, E.; Reylé, C.; Veljanoski,
J.; Brown, A. G. A.; Vallenari, A.; Prusti, T.; de Bruijne,
J. H. J.; Bailer-Jones, C. A. L.; Evans, D. W.; Eyer, L.; Jansen,
F.; Klioner, S. A.; Lammers, U.; Luri, X.; Mignard, F.; Panem,
C.; Pourbaix, D.; Randich, S.; Sartoretti, P.; Siddiqui, H. I.;
Soubiran, C.; Walton, N. A.; Cropper, M.; Drimmel, R.; Katz, D.;
Lattanzi, M. G.; Bakker, J.; Cacciari, C.; Castañeda, J.; Chaoul,
L.; Cheek, N.; De Angeli, F.; Fabricius, C.; Guerra, R.; Holl, B.;
Masana, E.; Messineo, R.; Mowlavi, N.; Nienartowicz, K.; Panuzzo,
P.; Portell, J.; Riello, M.; Seabroke, G. M.; Tanga, P.; Thévenin,
F.; Gracia-Abril, G.; Comoretto, G.; Garcia-Reinaldos, M.; Teyssier,
D.; Altmann, M.; Andrae, R.; Audard, M.; Bellas-Velidis, I.; Benson,
K.; Berthier, J.; Blomme, R.; Burgess, P.; Busso, G.; Carry, B.;
Cellino, A.; Clementini, G.; Clotet, M.; Creevey, O.; Davidson,
M.; De Ridder, J.; Delchambre, L.; Dell'Oro, A.; Ducourant, C.;
Fernández-Hernández, J.; Fouesneau, M.; Frémat, Y.; Galluccio, L.;
García-Torres, M.; González-Núñez, J.; González-Vidal, J. J.;
Gosset, E.; Guy, L. P.; Halbwachs, J. -L.; Hambly, N. C.; Harrison,
D. L.; Hernández, J.; Hestroffer, D.; Hodgkin, S. T.; Hutton, A.;
Jasniewicz, G.; Jean-Antoine-Piccolo, A.; Jordan, S.; Korn, A. J.;
Krone-Martins, A.; Lanzafame, A. C.; Lebzelter, T.; Löffler, W.;
Manteiga, M.; Marrese, P. M.; Martín-Fleitas, J. M.; Moitinho, A.;
Mora, A.; Muinonen, K.; Osinde, J.; Pauwels, T.; Petit, J. -M.;
Recio-Blanco, A.; Richards, P. J.; Rimoldini, L.; Sarro, L. M.;
Siopis, C.; Smith, M.; Sozzetti, A.; Süveges, M.; Torra, J.; van
Reeven, W.; Abbas, U.; Abreu Aramburu, A.; Accart, S.; Aerts, C.;
Altavilla, G.; Álvarez, M. A.; Alvarez, R.; Alves, J.; Anderson,
R. I.; Andrei, A. H.; Anglada Varela, E.; Antiche, E.; Arcay, B.;
Astraatmadja, T. L.; Bach, N.; Baker, S. G.; Balaguer-Núñez, L.;
Balm, P.; Barache, C.; Barata, C.; Barbato, D.; Barblan, F.; Barklem,
P. S.; Barrado, D.; Barros, M.; Barstow, M. A.; Bartholomé Muñoz,
S.; Bassilana, J. -L.; Becciani, U.; Bellazzini, M.; Berihuete, A.;
Bertone, S.; Bianchi, L.; Bienaymé, O.; Blanco-Cuaresma, S.; Boch,
T.; Boeche, C.; Bombrun, A.; Borrachero, R.; Bossini, D.; Bouquillon,
S.; Bourda, G.; Bragaglia, A.; Bramante, L.; Bressan, A.; Brouillet,
N.; Brüsemeister, T.; Brugaletta, E.; Bucciarelli, B.; Burlacu, A.;
Busonero, D.; Butkevich, A. G.; Buzzi, R.; Caffau, E.; Cancelliere,
R.; Cannizzaro, G.; Cantat-Gaudin, T.; Carballo, R.; Carlucci, T.;
Carrasco, J. M.; Casamiquela, L.; Castellani, M.; Castro-Ginard, A.;
Charlot, P.; Chemin, L.; Chiavassa, A.; Cocozza, G.; Costigan, G.;
Cowell, S.; Crifo, F.; Crosta, M.; Crowley, C.; Cuypers, J.; Dafonte,
C.; Damerdji, Y.; Dapergolas, A.; David, P.; David, M.; de Laverny,
P.; De Luise, F.; De March, R.; de Martino, D.; de Souza, R.; de
Torres, A.; Debosscher, J.; del Pozo, E.; Delbo, M.; Delgado, A.;
Delgado, H. E.; Di Matteo, P.; Diakite, S.; Diener, C.; Distefano,
E.; Dolding, C.; Drazinos, P.; Durán, J.; Edvardsson, B.; Enke, H.;
Eriksson, K.; Esquej, P.; Eynard Bontemps, G.; Fabre, C.; Fabrizio,
M.; Faigler, S.; Falcão, A. J.; Farràs Casas, M.; Federici, L.;
Fedorets, G.; Fernique, P.; Figueras, F.; Filippi, F.; Findeisen, K.;
Fonti, A.; Fraile, E.; Fraser, M.; Frézouls, B.; Gai, M.; Galleti,
S.; Garabato, D.; García-Sedano, F.; Garofalo, A.; Garralda, N.;
Gavel, A.; Gavras, P.; Gerssen, J.; Geyer, R.; Giacobbe, P.; Gilmore,
G.; Girona, S.; Giuffrida, G.; Glass, F.; Gomes, M.; Granvik, M.;
Gueguen, A.; Guerrier, A.; Guiraud, J.; Gutiérrez-Sánchez, R.;
Haigron, R.; Hatzidimitriou, D.; Hauser, M.; Haywood, M.; Heiter,
U.; Heu, J.; Hilger, T.; Hofmann, W.; Holland, G.; Huckle, H. E.;
Hypki, A.; Icardi, V.; Janßen, K.; Jevardat de Fombelle, G.; Jonker,
P. G.; Juhász, Á. L.; Julbe, F.; Karampelas, A.; Kewley, A.; Klar,
J.; Kochoska, A.; Kohley, R.; Kolenberg, K.; Kontizas, M.; Kontizas,
E.; Koposov, S. E.; Kordopatis, G.; Kostrzewa-Rutkowska, Z.; Koubsky,
P.; Lambert, S.; Lanza, A. F.; Lasne, Y.; Lavigne, J. -B.; Le Fustec,
Y.; Le Poncin-Lafitte, C.; Lebreton, Y.; Leccia, S.; Leclerc, N.;
Lecoeur-Taibi, I.; Lenhardt, H.; Leroux, F.; Liao, S.; Licata, E.;
Lindstrøm, H. E. P.; Lister, T. A.; Livanou, E.; Lobel, A.; López,
M.; Managau, S.; Mann, R. G.; Mantelet, G.; Marchal, O.; Marchant,
J. M.; Marconi, M.; Marinoni, S.; Marschalkó, G.; Marshall, D. J.;
Martino, M.; Marton, G.; Mary, N.; Matijevič, G.; Mazeh, T.; Messina,
S.; Michalik, D.; Millar, N. R.; Molina, D.; Molinaro, R.; Molnár,
L.; Montegriffo, P.; Mor, R.; Morbidelli, R.; Morel, T.; Morris, D.;
Mulone, A. F.; Muraveva, T.; Musella, I.; Nelemans, G.; Nicastro,
L.; Noval, L.; O'Mullane, W.; Ordénovic, C.; Ordóñez-Blanco,
D.; Osborne, P.; Pagani, C.; Pagano, I.; Pailler, F.; Palacin, H.;
Palaversa, L.; Panahi, A.; Pawlak, M.; Piersimoni, A. M.; Pineau,
F. -X.; Plachy, E.; Plum, G.; Poggio, E.; Poujoulet, E.; Prša, A.;
Pulone, L.; Racero, E.; Ragaini, S.; Rambaux, N.; Ramos-Lerate, M.;
Regibo, S.; Riclet, F.; Ripepi, V.; Riva, A.; Rivard, A.; Rixon, G.;
Roegiers, T.; Roelens, M.; Romero-Gómez, M.; Rowell, N.; Royer,
F.; Ruiz-Dern, L.; Sadowski, G.; Sagristà Sellés, T.; Sahlmann,
J.; Salgado, J.; Salguero, E.; Sanna, N.; Santana-Ros, T.; Sarasso,
M.; Savietto, H.; Schultheis, M.; Sciacca, E.; Segol, M.; Segovia,
J. C.; Ségransan, D.; Shih, I. -C.; Siltala, L.; Silva, A. F.; Smart,
R. L.; Smith, K. W.; Solano, E.; Solitro, F.; Sordo, R.; Soria Nieto,
S.; Souchay, J.; Spagna, A.; Spoto, F.; Stampa, U.; Steele, I. A.;
Steidelmüller, H.; Stephenson, C. A.; Stoev, H.; Suess, F. F.; Surdej,
J.; Szabados, L.; Szegedi-Elek, E.; Tapiador, D.; Taris, F.; Tauran,
G.; Taylor, M. B.; Teixeira, R.; Terrett, D.; Teyssandier, P.;
Thuillot, W.; Titarenko, A.; Torra Clotet, F.; Turon, C.; Ulla, A.;
Utrilla, E.; Uzzi, S.; Vaillant, M.; Valentini, G.; Valette, V.;
van Elteren, A.; Van Hemelryck, E.; van Leeuwen, M.; Vaschetto, M.;
Vecchiato, A.; Viala, Y.; Vicente, D.; Vogt, S.; von Essen, C.; Voss,
H.; Votruba, V.; Voutsinas, S.; Walmsley, G.; Weiler, M.; Wertz, O.;
Wevems, T.; Wyrzykowski, Ł.; Yoldas, A.; Žerjal, M.; Ziaeepour,
H.; Zorec, J.; Zschocke, S.; Zucker, S.; Zurbach, C.; Zwitter, T.
Bibcode: 2020A&A...637C...3G
Altcode:
No abstract at ADS
Title: VizieR Online Data Catalog: Gaia DR2. Variable stars in CMD
(Gaia Collaboration+, 2019)
Authors: Gaia Collaboration; Eyer, L.; Rimoldini, L.; Audard, M.;
Anderson, R. I.; Nienartowicz, K.; Glass, F.; Marchal, O.; Grenon, M.;
Mowlavi, N.; Holl, B.; Clementini, G.; Aerts, C.; Mazeh, T.; Evans,
D. W.; Szabados, L.; Brown, A. G. A.; Vallenari, A.; Prusti, T.; de
Bruijne, J. H. J.; Babusiaux, C.; Bailer-Jones, C. A. L.; Biermann,
M.; Jansen, F.; Jordi, C.; Klioner, S. A.; Lammers, U.; Lindegren,
L.; Luri, X.; Mignard, F.; Panem, C.; Pourbaix, D.; Randich, S.;
Sartoretti, P.; Siddiqui, H. I.; Soubiran, C.; van Leeuwen, F.;
Walton, N. A.; Arenou, F.; Bastian, U.; Cropper, M.; Drimmel, R.;
Katz, D.; Lattanzi, M. G.; Bakker, J.; Cacciari, C.; Castaneda,
J.; Chaoul, L.; Cheek, N.; de Angeli, F.; Fabricius, C.; Guerra,
R.; Masana, E.; Messineo, R.; Panuzzo, P.; Portell, J.; Riello, M.;
Seabroke, G. M.; Tanga, P.; Thevenin, F.; Gracia-Abril, G.; Comoretto,
G.; Garcia-Reinaldos, M.; Teyssier, D.; Altmann, M.; Andrae, R.;
Bellas-Velidis, I.; Benson, K.; Berthier, J.; Blomme, R.; Burgess,
P.; Busso, G.; Carry, B.; Cellino, A.; Clotet, M.; Creevey, O.;
Davidson, M.; de Ridder, J.; Delchambre, L.; Dell'Oro, A.; Ducourant,
C.; Fernandez-Hernandez, J.; Fouesneau, M.; Fremat, Y.; Galluccio, L.;
Garcia-Torres, M.; Gonzalez-Nunez, J.; Gonzalez-Vidal, J. J.; Gosset,
E.; Guy, L. P.; Halbwachs, J. -L.; Hambly, N. C.; Harrison, D. L.;
Hernandez, J.; Hestroer, D.; Hodgkin, S. T.; Hutton, A.; Jasniewicz,
G.; Jean-Antoine-Piccolo, A.; Jordan, S.; Korn, A. J.; Krone-Martins,
A.; Lanzafame, A. C.; Lebzelter, T.; Loeer, W.; Manteiga, M.; Marrese,
P. M.; Martin-Fleitas, J. M.; Moitinho, A.; Mora, A.; Muinonen, K.;
Osinde, J.; Pancino, E.; Pauwels, T.; Petit, J. -M.; Recio-Blanco,
A.; Richards, P. J.; Robin, A. C.; Sarro, L. M.; Siopis, C.; Smith,
M.; Sozzetti, A.; Sueveges, M.; Torra, J.; van Reeven, W.; Abbas,
U.; Abreu Aramburu, A.; Accart, S.; Altavilla, G.; Alvarez, M. A.;
Alvarez, R.; Alves, J.; Andrei, A. H.; Anglada Varela, E.; Antiche, E.;
Antoja, T.; Arcay, B.; Astraatmadja, T. L.; Bach, N.; Baker, S. G.;
Balaguer-Nunez, L.; Balm, P.; Barache, C.; Barata, C.; Barbato, D.;
Barblan, F.; Barklem, P. S.; Barrado, D.; Barros, M.; Barstow, M. A.;
Bartholome Munoz, S.; Bassilana, J. -L.; Becciani, U.; Bellazzini, M.;
Berihuete, A.; Bertone, S.; Bianchi, L.; Bienayme, O.; Blanco-Cuaresma,
S.; Boch, T.; Boeche, C.; Bombrun, A.; Borrachero, R.; Bossini, D.;
Bouquillon, S.; Bourda, G.; Bragaglia, A.; Bramante, L.; Breddels,
M. A.; Bressan, A.; Brouillet, N.; Bruesemeister, T.; Brugaletta,
E.; Bucciarelli, B.; Burlacu, A.; Busonero, D.; Butkevich, A. G.;
Buzzi, R.; Caau, E.; Cancelliere, R.; Cannizzaro, G.; Cantat-Gaudin,
T.; Carballo, R.; Carlucci, T.; Carrasco, J. M.; Casamiquela, L.;
Castellani, M.; Castro-Ginard, A.; Charlot, P.; Chemin, L.; Chiavassa,
A.; Cocozza, G.; Costigan, G.; Cowell, S.; Crifo, F.; Crosta, M.;
Crowley, C.; Cuypersy, J.; Dafonte, C.; Damerdji, Y.; Dapergolas,
A.; David, P.; David, M.; de Laverny, P.; de Luise, F.; de March,
R.; de Martino, D.; de Souza, R.; de Torres, A.; Debosscher, J.;
Del Pozo, E.; Delbo, M.; Delgado, A.; Delgado, H. E.; Diakite, S.;
Diener, C.; Distefano, E.; Dolding, C.; Drazinos, P.; Duran, J.;
Edvardsson, B.; Enke, H.; Eriksson, K.; Esquej, P.; Eynard Bontemps,
G.; Fabre, C.; Fabrizio, M.; Faigler, S.; Falcao, A. J.; Farras Casas,
M.; Federici, L.; Fedorets, G.; Fernique, P.; Figueras, F.; Filippi,
F.; Findeisen, K.; Fonti, A.; Fraile, E.; Fraser, M.; Frezouls, B.;
Gai, M.; Galleti, S.; Garabato, D.; Garcia-Sedano, F.; Garofalo, A.;
Garralda, N.; Gavel, A.; Gavras, P.; Gerssen, J.; Geyer, R.; Giacobbe,
P.; Gilmore, G.; Girona, S.; Giurida, G.; Gomes, M.; Granvik, M.;
Gueguen, A.; Guerrier, A.; Guiraud, J.; Gutierrez-Sanchez, R.; Haigron,
R.; Hatzidimitriou, D.; Hauser, M.; Haywood, M.; Heiter, U.; Helmi,
A.; Heu, J.; Hilger, T.; Hobbs, D.; Hofmann, W.; Holland, G.; Huckle,
H. E.; Hypki, A.; Icardi, V.; Janssen, K.; Jevardat de Fombelle,
G.; Jonker, P. G.; Juhasz, A. L.; Julbe, F.; Karampelas, A.; Kewley,
A.; Klar, J.; Kochoska, A.; Kohley, R.; Kolenberg, K.; Kontizas, M.;
Kontizas, E.; Koposov, S. E.; Kordopatis, G.; Kostrzewa-Rutkowska, Z.;
Koubsky, P.; Lambert, S.; Lanza, A. F.; Lasne, Y.; Lavigne, J. -B.;
Le Fustec, Y.; Le Poncin-Lafitte, C.; Lebreton, Y.; Leccia, S.;
Leclerc, N.; Lecoeur-Taibi, I.; Lenhardt, H.; Leroux, F.; Liao, S.;
Licata, E.; Lindstrom, H. E. P.; Lister, T. A.; Livanou, E.; Lobel,
A.; Lopez, M.; Lorenz, D.; Managau, S.; Mann, R. G.; Mantelet, G.;
Marchant, J. M.; Marconi, M.; Marinoni, S.; Marschalko, G.; Marshall,
D. J.; Martino, M.; Marton, G.; Mary, N.; Massari, D.; Matijevic, G.;
McMillan, P. J.; Messina, S.; Michalik, D.; Millar, N. R.; Molina,
D.; Molinaro, R.; Molnar, L.; Montegrio, P.; Mor, R.; Morbidelli, R.;
Morel, T.; Morgenthaler, S.; Morris, D.; Mulone, A. F.; Muraveva, T.;
Musella, I.; Nelemans, G.; Nicastro, L.; Noval, L.; O'Mullane, W.;
Ordenovic, C.; Ordonez-Blanco, D.; Osborne, P.; Pagani, C.; Pagano,
I.; Pailler, F.; Palacin, H.; Palaversa, L.; Panahi, A.; Pawlak, M.;
Piersimoni, A. M.; Pineau, F. -X.; Plachy, E.; Plum, G.; Poggio,
E.; Poujoulet, E.; Prsa, A.; Pulone, L.; Racero, E.; Ragaini, S.;
Rambaux, N.; Ramos-Lerate, M.; Regibo, S.; Reyle, C.; Riclet, F.;
Ripepi, V.; Riva, A.; Rivard, A.; Rixon, G.; Roegiers, T.; Roelens,
M.; Romero-Gomez, M.; Rowell, N.; Royer, F.; Ruiz-Dern, L.; Sadowski,
G.; Sagrista Selles, T.; Sahlmann, J.; Salgado, J.; Salguero, E.;
Sanna, N.; Santana-Ros, T.; Sarasso, M.; Savietto, H.; Schultheis, M.;
Sciacca, E.; Segol, M.; Segovia, J. C.; Segransan, D.; Shih, I. -C.;
Siltala, L.; Silva, A. F.; Smart, R. L.; Smith, K. W.; Solano, E.;
Solitro, F.; Sordo, R.; Soria Nieto, S.; Souchay, J.; Spagna, A.;
Spoto, F.; Stampa, U.; Steele, I. A.; Steidelmueller, H.; Stephenson,
C. A.; Stoev, H.; Suess, F. F.; Surdej, J.; Szegedi-Elek, E.; Tapiador,
D.; Taris, F.; Tauran, G.; Taylor, M. B.; Teixeira, R.; Terrett, D.;
Teyssandier, P.; Thuillot, W.; Titarenko, A.; Torra Clotet, F.; Turon,
C.; Ulla, A.; Utrilla, E.; Uzzi, S.; Vaillant, M.; Valentini, G.;
Valette, V.; van Elteren, A.; van Hemelryck, E.; van Leeuwen, M.;
Vaschetto, M.; Vecchiato, A.; Veljanoski, J.; Viala, Y.; Vicente,
D.; Vogt, S.; von Essen, C.; Voss, H.; Votruba, V.; Voutsinas, S.;
Walmsley, G.; Weiler, M.; Wertz, O.; Wevers, T.; Wyrzykowski, L.;
Yoldas, A.; Zerjal, M.; Ziaeepour, H.; Zorec, J.; Zschocke, S.;
Zucker, S.; Zurbach, C.; Zwitter, T.
Bibcode: 2019yCat..36230110G
Altcode:
Time series in the G, BP, and RP bands of the selected field-of-view
transits for 224 sources that are not published in Gaia DR2, but
are plotted in Fig. 11. An animated version of Fig. 11 is provided
online and at https://www.cosmos.esa.int/web/gaia/gaiadr2_cu7. (2
data files).
Title: Gaia Data Release 2. Variable stars in the colour-absolute
magnitude diagram
Authors: Gaia Collaboration; Eyer, L.; Rimoldini, L.; Audard, M.;
Anderson, R. I.; Nienartowicz, K.; Glass, F.; Marchal, O.; Grenon,
M.; Mowlavi, N.; Holl, B.; Clementini, G.; Aerts, C.; Mazeh, T.;
Evans, D. W.; Szabados, L.; Brown, A. G. A.; Vallenari, A.; Prusti,
T.; de Bruijne, J. H. J.; Babusiaux, C.; Bailer-Jones, C. A. L.;
Biermann, M.; Jansen, F.; Jordi, C.; Klioner, S. A.; Lammers, U.;
Lindegren, L.; Luri, X.; Mignard, F.; Panem, C.; Pourbaix, D.; Randich,
S.; Sartoretti, P.; Siddiqui, H. I.; Soubiran, C.; van Leeuwen, F.;
Walton, N. A.; Arenou, F.; Bastian, U.; Cropper, M.; Drimmel, R.;
Katz, D.; Lattanzi, M. G.; Bakker, J.; Cacciari, C.; Castañeda,
J.; Chaoul, L.; Cheek, N.; De Angeli, F.; Fabricius, C.; Guerra,
R.; Masana, E.; Messineo, R.; Panuzzo, P.; Portell, J.; Riello, M.;
Seabroke, G. M.; Tanga, P.; Thévenin, F.; Gracia-Abril, G.; Comoretto,
G.; Garcia-Reinaldos, M.; Teyssier, D.; Altmann, M.; Andrae, R.;
Bellas-Velidis, I.; Benson, K.; Berthier, J.; Blomme, R.; Burgess,
P.; Busso, G.; Carry, B.; Cellino, A.; Clotet, M.; Creevey, O.;
Davidson, M.; De Ridder, J.; Delchambre, L.; Dell'Oro, A.; Ducourant,
C.; Fernández-Hernández, J.; Fouesneau, M.; Frémat, Y.; Galluccio,
L.; García-Torres, M.; González-Núñez, J.; González-Vidal, J. J.;
Gosset, E.; Guy, L. P.; Halbwachs, J. -L.; Hambly, N. C.; Harrison,
D. L.; Hernández, J.; Hestroffer, D.; Hodgkin, S. T.; Hutton, A.;
Jasniewicz, G.; Jean-Antoine-Piccolo, A.; Jordan, S.; Korn, A. J.;
Krone-Martins, A.; Lanzafame, A. C.; Lebzelter, T.; Löffler, W.;
Manteiga, M.; Marrese, P. M.; Martín-Fleitas, J. M.; Moitinho, A.;
Mora, A.; Muinonen, K.; Osinde, J.; Pancino, E.; Pauwels, T.; Petit,
J. -M.; Recio-Blanco, A.; Richards, P. J.; Robin, A. C.; Sarro,
L. M.; Siopis, C.; Smith, M.; Sozzetti, A.; Süveges, M.; Torra, J.;
van Reeven, W.; Abbas, U.; Abreu Aramburu, A.; Accart, S.; Altavilla,
G.; Álvarez, M. A.; Alvarez, R.; Alves, J.; Andrei, A. H.; Anglada
Varela, E.; Antiche, E.; Antoja, T.; Arcay, B.; Astraatmadja, T. L.;
Bach, N.; Baker, S. G.; Balaguer-Núñez, L.; Balm, P.; Barache,
C.; Barata, C.; Barbato, D.; Barblan, F.; Barklem, P. S.; Barrado,
D.; Barros, M.; Barstow, M. A.; Bartholomé Muñoz, S.; Bassilana,
J. -L.; Becciani, U.; Bellazzini, M.; Berihuete, A.; Bertone, S.;
Bianchi, L.; Bienaymé, O.; Blanco-Cuaresma, S.; Boch, T.; Boeche, C.;
Bombrun, A.; Borrachero, R.; Bossini, D.; Bouquillon, S.; Bourda, G.;
Bragaglia, A.; Bramante, L.; Breddels, M. A.; Bressan, A.; Brouillet,
N.; Brüsemeister, T.; Brugaletta, E.; Bucciarelli, B.; Burlacu, A.;
Busonero, D.; Butkevich, A. G.; Buzzi, R.; Caffau, E.; Cancelliere,
R.; Cannizzaro, G.; Cantat-Gaudin, T.; Carballo, R.; Carlucci, T.;
Carrasco, J. M.; Casamiquela, L.; Castellani, M.; Castro-Ginard, A.;
Charlot, P.; Chemin, L.; Chiavassa, A.; Cocozza, G.; Costigan, G.;
Cowell, S.; Crifo, F.; Crosta, M.; Crowley, C.; Cuypers, J.; Dafonte,
C.; Damerdji, Y.; Dapergolas, A.; David, P.; David, M.; de Laverny, P.;
De Luise, F.; De March, R.; de Martino, D.; de Souza, R.; de Torres,
A.; Debosscher, J.; del Pozo, E.; Delbo, M.; Delgado, A.; Delgado,
H. E.; Diakite, S.; Diener, C.; Distefano, E.; Dolding, C.; Drazinos,
P.; Durán, J.; Edvardsson, B.; Enke, H.; Eriksson, K.; Esquej, P.;
Eynard Bontemps, G.; Fabre, C.; Fabrizio, M.; Faigler, S.; Falcão,
A. J.; Farràs Casas, M.; Federici, L.; Fedorets, G.; Fernique,
P.; Figueras, F.; Filippi, F.; Findeisen, K.; Fonti, A.; Fraile,
E.; Fraser, M.; Frézouls, B.; Gai, M.; Galleti, S.; Garabato, D.;
García-Sedano, F.; Garofalo, A.; Garralda, N.; Gavel, A.; Gavras,
P.; Gerssen, J.; Geyer, R.; Giacobbe, P.; Gilmore, G.; Girona, S.;
Giuffrida, G.; Gomes, M.; Granvik, M.; Gueguen, A.; Guerrier, A.;
Guiraud, J.; Gutiérrez-Sánchez, R.; Haigron, R.; Hatzidimitriou,
D.; Hauser, M.; Haywood, M.; Heiter, U.; Helmi, A.; Heu, J.; Hilger,
T.; Hobbs, D.; Hofmann, W.; Holland, G.; Huckle, H. E.; Hypki, A.;
Icardi, V.; Janßen, K.; Jevardat de Fombelle, G.; Jonker, P. G.;
Juhász, Á. L.; Julbe, F.; Karampelas, A.; Kewley, A.; Klar, J.;
Kochoska, A.; Kohley, R.; Kolenberg, K.; Kontizas, M.; Kontizas, E.;
Koposov, S. E.; Kordopatis, G.; Kostrzewa-Rutkowska, Z.; Koubsky, P.;
Lambert, S.; Lanza, A. F.; Lasne, Y.; Lavigne, J. -B.; Le Fustec,
Y.; Le Poncin-Lafitte, C.; Lebreton, Y.; Leccia, S.; Leclerc, N.;
Lecoeur-Taibi, I.; Lenhardt, H.; Leroux, F.; Liao, S.; Licata, E.;
Lindstrøm, H. E. P.; Lister, T. A.; Livanou, E.; Lobel, A.; López,
M.; Lorenz, D.; Managau, S.; Mann, R. G.; Mantelet, G.; Marchant,
J. M.; Marconi, M.; Marinoni, S.; Marschalkó, G.; Marshall, D. J.;
Martino, M.; Marton, G.; Mary, N.; Massari, D.; Matijevič, G.;
McMillan, P. J.; Messina, S.; Michalik, D.; Millar, N. R.; Molina,
D.; Molinaro, R.; Molnár, L.; Montegriffo, P.; Mor, R.; Morbidelli,
R.; Morel, T.; Morgenthaler, S.; Morris, D.; Mulone, A. F.; Muraveva,
T.; Musella, I.; Nelemans, G.; Nicastro, L.; Noval, L.; O'Mullane,
W.; Ordénovic, C.; Ordóñez-Blanco, D.; Osborne, P.; Pagani, C.;
Pagano, I.; Pailler, F.; Palacin, H.; Palaversa, L.; Panahi, A.;
Pawlak, M.; Piersimoni, A. M.; Pineau, F. -X.; Plachy, E.; Plum,
G.; Poggio, E.; Poujoulet, E.; Prša, A.; Pulone, L.; Racero, E.;
Ragaini, S.; Rambaux, N.; Ramos-Lerate, M.; Regibo, S.; Reylé, C.;
Riclet, F.; Ripepi, V.; Riva, A.; Rivard, A.; Rixon, G.; Roegiers,
T.; Roelens, M.; Romero-Gómez, M.; Rowell, N.; Royer, F.; Ruiz-Dern,
L.; Sadowski, G.; Sagristà Sellés, T.; Sahlmann, J.; Salgado, J.;
Salguero, E.; Sanna, N.; Santana-Ros, T.; Sarasso, M.; Savietto, H.;
Schultheis, M.; Sciacca, E.; Segol, M.; Segovia, J. C.; Ségransan, D.;
Shih, I. -C.; Siltala, L.; Silva, A. F.; Smart, R. L.; Smith, K. W.;
Solano, E.; Solitro, F.; Sordo, R.; Soria Nieto, S.; Souchay, J.;
Spagna, A.; Spoto, F.; Stampa, U.; Steele, I. A.; Steidelmüller, H.;
Stephenson, C. A.; Stoev, H.; Suess, F. F.; Surdej, J.; Szegedi-Elek,
E.; Tapiador, D.; Taris, F.; Tauran, G.; Taylor, M. B.; Teixeira,
R.; Terrett, D.; Teyssandier, P.; Thuillot, W.; Titarenko, A.; Torra
Clotet, F.; Turon, C.; Ulla, A.; Utrilla, E.; Uzzi, S.; Vaillant,
M.; Valentini, G.; Valette, V.; van Elteren, A.; Van Hemelryck,
E.; van Leeuwen, M.; Vaschetto, M.; Vecchiato, A.; Veljanoski, J.;
Viala, Y.; Vicente, D.; Vogt, S.; von Essen, C.; Voss, H.; Votruba,
V.; Voutsinas, S.; Walmsley, G.; Weiler, M.; Wertz, O.; Wevers, T.;
Wyrzykowski, Ł.; Yoldas, A.; Žerjal, M.; Ziaeepour, H.; Zorec, J.;
Zschocke, S.; Zucker, S.; Zurbach, C.; Zwitter, T.
Bibcode: 2019A&A...623A.110G
Altcode: 2018arXiv180409382G
Context. The ESA Gaia mission provides a unique time-domain survey
for more than 1.6 billion sources with G ≲ 21 mag.
Aims:
We showcase stellar variability in the Galactic colour-absolute
magnitude diagram (CaMD). We focus on pulsating, eruptive, and
cataclysmic variables, as well as on stars that exhibit variability
that is due to rotation and eclipses.
Methods: We describe
the locations of variable star classes, variable object fractions,
and typical variability amplitudes throughout the CaMD and show
how variability-related changes in colour and brightness induce
"motions". To do this, we use 22 months of calibrated photometric,
spectro-photometric, and astrometric Gaia data of stars with a
significant parallax. To ensure that a large variety of variable
star classes populate the CaMD, we crossmatched Gaia sources with
known variable stars. We also used the statistics and variability
detection modules of the Gaia variability pipeline. Corrections for
interstellar extinction are not implemented in this article.
Results: Gaia enables the first investigation of Galactic variable
star populations in the CaMD on a similar, if not larger, scale as
was previously done in the Magellanic Clouds. Although the observed
colours are not corrected for reddening, distinct regions are visible
in which variable stars occur. We determine variable star fractions
to within the current detection thresholds of Gaia. Finally,
we report the most complete description of variability-induced
motion within the CaMD to date.
Conclusions: Gaia enables
novel insights into variability phenomena for an unprecedented
number of stars, which will benefit the understanding of stellar
astrophysics. The CaMD of Galactic variable stars provides crucial
information on physical origins of variability in a way that
has previously only been accessible for Galactic star clusters or
external galaxies. Future Gaia data releases will enable significant
improvements over this preview by providing longer time series, more
accurate astrometry, and additional data types (time series BP and
RP spectra, RVS spectra, and radial velocities), all for much larger
samples of stars. A movie associated to Fig. 11 is available at https://www.aanda.org.Data
are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr
(ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/623/A110.
Title: VizieR Online Data Catalog: Gaia DR2 white dwarf candidates
(Gentile Fusillo+, 2019)
Authors: Gentile Fusillo, N. P.; Tremblay, P. -E.; Gaensicke, B. T.;
Manser, C. J.; Cunningham, T.; Cukanovaite, E.; Hollands, M.; Marsh,
T.; Raddi, R.; Jordan, S.; Toonen, S.; Geier, S.; Barstow, M.;
Cummings, J. D.
Bibcode: 2019yCat..74824570G
Altcode:
The main catalogue provides 486,641 stars selected from Gaia DR2 with
calculated probabilities of being a white dwarf (PWD). The PWD values
can used to reliably select high-confidence white dwarf candidates
with a flexible compromise between completeness and level of potential
contamination. As a generic guideline selecting objects with PWD>0.75
recovers 96 per cent of the spectroscopically confirmed white dwarfs
from SDSS and only 1 per cent of the contaminant (non white dwarfs)
objects. All Gaia sources in the catalogue have also been cross
matched with SDSS DR14 taking into account the difference in epoch of
observation and proper motions. Whether available we include SDSS ugriz
photometry. In a separate table we provide informations on all the
available SDSS spectra for the Gaia sources in the main catalogue. (2 data files).
Title: VizieR Online Data Catalog: Gaia DR1 mass-radius relation of
white dwarfs (Tremblay+ 2017)
Authors: Tremblay, P. -E.; Gentile-Fusillo, N.; Raddi, R.; Jordan,
S.; Besson, C.; Gansicke, B. T.; Parsons, S. G.; Koester, D.; Marsh,
T.; Bohlin, R.; Kalirai, J.; Deustua, S.
Bibcode: 2018yCat..74652849T
Altcode:
The Gaia DR1 (Cat. I/337) sample of parallaxes was presented for 6
directly observed white dwarfs and 46 members of wide binaries. By
combining this data set with spectroscopic atmospheric parameters,
we have derived the semi-empirical MRR relation for white dwarfs. (5 data files).
Title: Gaia Data Release 2. Observations of solar system objects
Authors: Gaia Collaboration; Spoto, F.; Tanga, P.; Mignard, F.;
Berthier, J.; Carry, B.; Cellino, A.; Dell'Oro, A.; Hestroffer, D.;
Muinonen, K.; Pauwels, T.; Petit, J. -M.; David, P.; De Angeli, F.;
Delbo, M.; Frézouls, B.; Galluccio, L.; Granvik, M.; Guiraud, J.;
Hernández, J.; Ordénovic, C.; Portell, J.; Poujoulet, E.; Thuillot,
W.; Walmsley, G.; Brown, A. G. A.; Vallenari, A.; Prusti, T.; de
Bruijne, J. H. J.; Babusiaux, C.; Bailer-Jones, C. A. L.; Biermann,
M.; Evans, D. W.; Eyer, L.; Jansen, F.; Jordi, C.; Klioner, S. A.;
Lammers, U.; Lindegren, L.; Luri, X.; Panem, C.; Pourbaix, D.; Randich,
S.; Sartoretti, P.; Siddiqui, H. I.; Soubiran, C.; van Leeuwen, F.;
Walton, N. A.; Arenou, F.; Bastian, U.; Cropper, M.; Drimmel, R.;
Katz, D.; Lattanzi, M. G.; Bakker, J.; Cacciari, C.; Castañeda, J.;
Chaoul, L.; Cheek, N.; Fabricius, C.; Guerra, R.; Holl, B.; Masana,
E.; Messineo, R.; Mowlavi, N.; Nienartowicz, K.; Panuzzo, P.; Riello,
M.; Seabroke, G. M.; Thévenin, F.; Gracia-Abril, G.; Comoretto,
G.; Garcia-Reinaldos, M.; Teyssier, D.; Altmann, M.; Andrae, R.;
Audard, M.; Bellas-Velidis, I.; Benson, K.; Blomme, R.; Burgess, P.;
Busso, G.; Clementini, G.; Clotet, M.; Creevey, O.; Davidson, M.; De
Ridder, J.; Delchambre, L.; Ducourant, C.; Fernández-Hernández, J.;
Fouesneau, M.; Frémat, Y.; García-Torres, M.; González-Núñez,
J.; González-Vidal, J. J.; Gosset, E.; Guy, L. P.; Halbwachs,
J. -L.; Hambly, N. C.; Harrison, D. L.; Hodgkin, S. T.; Hutton,
A.; Jasniewicz, G.; Jean-Antoine-Piccolo, A.; Jordan, S.; Korn,
A. J.; Krone-Martins, A.; Lanzafame, A. C.; Lebzelter, T.; Lö, W.;
Manteiga, M.; Marrese, P. M.; Martín-Fleitas, J. M.; Moitinho, A.;
Mora, A.; Osinde, J.; Pancino, E.; Recio-Blanco, A.; Richards, P. J.;
Rimoldini, L.; Robin, A. C.; Sarro, L. M.; Siopis, C.; Smith, M.;
Sozzetti, A.; Süveges, M.; Torra, J.; van Reeven, W.; Abbas, U.;
Abreu Aramburu, A.; Accart, S.; Aerts, C.; Altavilla, G.; Álvarez,
M. A.; Alvarez, R.; Alves, J.; Anderson, R. I.; Andrei, A. H.; Anglada
Varela, E.; Antiche, E.; Antoja, T.; Arcay, B.; Astraatmadja, T. L.;
Bach, N.; Baker, S. G.; Balaguer-Núñez, L.; Balm, P.; Barache,
C.; Barata, C.; Barbato, D.; Barblan, F.; Barklem, P. S.; Barrado,
D.; Barros, M.; Barstow, M. A.; Bartholomé Muñoz, L.; Bassilana,
J. -L.; Becciani, U.; Bellazzini, M.; Berihuete, A.; Bertone, S.;
Bianchi, L.; Bienaymé, O.; Blanco-Cuaresma, S.; Boch, T.; Boeche, C.;
Bombrun, A.; Borrachero, R.; Bossini, D.; Bouquillon, S.; Bourda, G.;
Bragaglia, A.; Bramante, L.; Breddels, M. A.; Bressan, A.; Brouillet,
N.; Brüsemeister, T.; Brugaletta, E.; Bucciarelli, B.; Burlacu, A.;
Busonero, D.; Butkevich, A. G.; Buzzi, R.; Caffau, E.; Cancelliere,
R.; Cannizzaro, G.; Cantat-Gaudin, T.; Carballo, R.; Carlucci, T.;
Carrasco, J. M.; Casamiquela, L.; Castellani, M.; Castro-Ginard,
A.; Charlot, P.; Chemin, L.; Chiavassa, A.; Cocozza, G.; Costigan,
G.; Cowell, S.; Crifo, F.; Crosta, M.; Crowley, C.; Cuypers, J.;
Dafonte, C.; Damerdji, Y.; Dapergolas, A.; David, M.; de Laverny, P.;
De Luise, F.; De March, R.; de Souza, R.; de Torres, A.; Debosscher,
J.; del Pozo, E.; Delgado, A.; Delgado, H. E.; Diakite, S.; Diener,
C.; Distefano, E.; Dolding, C.; Drazinos, P.; Durán, J.; Edvardsson,
B.; Enke, H.; Eriksson, K.; Esquej, P.; Eynard Bontemps, G.; Fabre,
C.; Fabrizio, M.; Faigler, S.; Falcão, A. J.; Farràs Casas, M.;
Federici, L.; Fedorets, G.; Fernique, P.; Figueras, F.; Filippi, F.;
Findeisen, K.; Fonti, A.; Fraile, E.; Fraser, M.; Gai, M.; Galleti, S.;
Garabato, D.; García-Sedano, F.; Garofalo, A.; Garralda, N.; Gavel,
A.; Gavras, P.; Gerssen, J.; Geyer, R.; Giacobbe, P.; Gilmore, G.;
Girona, S.; Giuffrida, G.; Glass, F.; Gomes, M.; Gueguen, A.; Guerrier,
A.; Gutié, R.; Haigron, R.; Hatzidimitriou, D.; Hauser, M.; Haywood,
M.; Heiter, U.; Helmi, A.; Heu, J.; Hilger, T.; Hobbs, D.; Hofmann,
W.; Holland, G.; Huckle, H. E.; Hypki, A.; Icardi, V.; Janßen, K.;
Jevardat de Fombelle, G.; Jonker, P. G.; Juhász, Á. L.; Julbe,
F.; Karampelas, A.; Kewley, A.; Klar, J.; Kochoska, A.; Kohley, R.;
Kolenberg, K.; Kontizas, M.; Kontizas, E.; Koposov, S. E.; Kordopatis,
G.; Kostrzewa-Rutkowska, Z.; Koubsky, P.; Lambert, S.; Lanza, A. F.;
Lasne, Y.; Lavigne, J. -B.; Le Fustec, Y.; Le Poncin-Lafitte, C.;
Lebreton, Y.; Leccia, S.; Leclerc, N.; Lecoeur-Taibi, I.; Lenhardt,
H.; Leroux, F.; Liao, S.; Licata, E.; Lindstrøm, H. E. P.; Lister,
T. A.; Livanou, E.; Lobel, A.; López, M.; Managau, S.; Mann, R. G.;
Mantelet, G.; Marchal, O.; Marchant, J. M.; Marconi, M.; Marinoni,
S.; Marschalkó, G.; Marshall, D. J.; Martino, M.; Marton, G.; Mary,
N.; Massari, D.; Matijevič, G.; Mazeh, T.; McMillan, P. J.; Messina,
S.; Michalik, D.; Millar, N. R.; Molina, D.; Molinaro, R.; Molnár,
L.; Montegriffo, P.; Mor, R.; Morbidelli, R.; Morel, T.; Morris, D.;
Mulone, A. F.; Muraveva, T.; Musella, I.; Nelemans, G.; Nicastro, L.;
Noval, L.; O'Mullane, W.; Ordóñez-Blanco, D.; Osborne, P.; Pagani,
C.; Pagano, I.; Pailler, F.; Palacin, H.; Palaversa, L.; Panahi, A.;
Pawlak, M.; Piersimoni, A. M.; Pineau, F. -X.; Plachy, E.; Plum, G.;
Poggio, E.; Prša, A.; Pulone, L.; Racero, E.; Ragaini, S.; Rambaux,
N.; Ramos-Lerate, M.; Regibo, S.; Reylé, C.; Riclet, F.; Ripepi,
V.; Riva, A.; Rivard, A.; Rixon, G.; Roegiers, T.; Roelens, M.;
Romero-Gómez, M.; Rowell, N.; Royer, F.; Ruiz-Dern, L.; Sadowski,
G.; Sagristà Sellés, T.; Sahlmann, J.; Salgado, J.; Salguero, E.;
Sanna, N.; Santana-Ros, T.; Sarasso, M.; Savietto, H.; Schultheis, M.;
Sciacca, E.; Segol, M.; Segovia, J. C.; Ségransan, D.; Shih, I. -C.;
Siltala, L.; Silva, A. F.; Smart, R. L.; Smith, K. W.; Solano, E.;
Solitro, F.; Sordo, R.; Soria Nieto, S.; Souchay, J.; Spagna, A.;
Stampa, U.; Steele, I. A.; Steidelmüller, H.; Stephenson, C. A.;
Stoev, H.; Suess, F. F.; Surdej, J.; Szabados, L.; Szegedi-Elek, E.;
Tapiador, D.; Taris, F.; Tauran, G.; Taylor, M. B.; Teixeira, R.;
Terrett, D.; Teyssandier, P.; Titarenko, A.; Torra Clotet, F.; Turon,
C.; Ulla, A.; Utrilla, E.; Uzzi, S.; Vaillant, M.; Valentini, G.;
Valette, V.; van Elteren, A.; Van Hemelryck, E.; van Leeuwen, M.;
Vaschetto, M.; Vecchiato, A.; Veljanoski, J.; Viala, Y.; Vicente,
D.; Vogt, S.; von Essen, C.; Voss, H.; Votruba, V.; Voutsinas, S.;
Weiler, M.; Wertz, O.; Wevers, T.; Wyrzykowski, Ł.; Yoldas, A.;
Žerjal, M.; Ziaeepour, H.; Zorec, J.; Zschocke, S.; Zucker, S.;
Zurbach, C.; Zwitter, T.
Bibcode: 2018A&A...616A..13G
Altcode: 2018arXiv180409379G
Context. The Gaia spacecraft of the European Space Agency (ESA)
has been securing observations of solar system objects (SSOs) since
the beginning of its operations. Data Release 2 (DR2) contains the
observations of a selected sample of 14,099 SSOs. These asteroids have
been already identified and have been numbered by the Minor Planet
Center repository. Positions are provided for each Gaia observation at
CCD level. As additional information, complementary to astrometry, the
apparent brightness of SSOs in the unfiltered G band is also provided
for selected observations.
Aims: We explain the processing of SSO
data, and describe the criteria we used to select the sample published
in Gaia DR2. We then explore the data set to assess its quality.
Methods: To exploit the main data product for the solar system in Gaia
DR2, which is the epoch astrometry of asteroids, it is necessary to take
into account the unusual properties of the uncertainty, as the position
information is nearly one-dimensional. When this aspect is handled
appropriately, an orbit fit can be obtained with post-fit residuals
that are overall consistent with the a-priori error model that was used
to define individual values of the astrometric uncertainty. The role
of both random and systematic errors is described. The distribution
of residuals allowed us to identify possible contaminants in the
data set (such as stars). Photometry in the G band was compared
to computed values from reference asteroid shapes and to the flux
registered at the corresponding epochs by the red and blue photometers
(RP and BP).
Results: The overall astrometric performance is
close to the expectations, with an optimal range of brightness G 12 -
17. In this range, the typical transit-level accuracy is well below
1 mas. For fainter asteroids, the growing photon noise deteriorates
the performance. Asteroids brighter than G 12 are affected by a lower
performance of the processing of their signals. The dramatic improvement
brought by Gaia DR2 astrometry of SSOs is demonstrated by comparisons
to the archive data and by preliminary tests on the detection of subtle
non-gravitational effects.
Title: Gaia Data Release 2. The celestial reference frame (Gaia-CRF2)
Authors: Gaia Collaboration; Mignard, F.; Klioner, S. A.; Lindegren,
L.; Hernández, J.; Bastian, U.; Bombrun, A.; Hobbs, D.; Lammers, U.;
Michalik, D.; Ramos-Lerate, M.; Biermann, M.; Fernández-Hernández,
J.; Geyer, R.; Hilger, T.; Siddiqui, H. I.; Steidelmüller, H.;
Babusiaux, C.; Barache, C.; Lambert, S.; Andrei, A. H.; Bourda, G.;
Charlot, P.; Brown, A. G. A.; Vallenari, A.; Prusti, T.; de Bruijne,
J. H. J.; Bailer-Jones, C. A. L.; Evans, D. W.; Eyer, L.; Jansen, F.;
Jordi, C.; Luri, X.; Panem, C.; Pourbaix, D.; Randich, S.; Sartoretti,
P.; Soubiran, C.; van Leeuwen, F.; Walton, N. A.; Arenou, F.; Cropper,
M.; Drimmel, R.; Katz, D.; Lattanzi, M. G.; Bakker, J.; Cacciari,
C.; Castañeda, J.; Chaoul, L.; Cheek, N.; De Angeli, F.; Fabricius,
C.; Guerra, R.; Holl, B.; Masana, E.; Messineo, R.; Mowlavi, N.;
Nienartowicz, K.; Panuzzo, P.; Portell, J.; Riello, M.; Seabroke,
G. M.; Tanga, P.; Thévenin, F.; Gracia-Abril, G.; Comoretto,
G.; Garcia-Reinaldos, M.; Teyssier, D.; Altmann, M.; Andrae, R.;
Audard, M.; Bellas-Velidis, I.; Benson, K.; Berthier, J.; Blomme,
R.; Burgess, P.; Busso, G.; Carry, B.; Cellino, A.; Clementini, G.;
Clotet, M.; Creevey, O.; Davidson, M.; De Ridder, J.; Delchambre, L.;
Dell'Oro, A.; Ducourant, C.; Fouesneau, M.; Frémat, Y.; Galluccio,
L.; García-Torres, M.; González-Núñez, J.; González-Vidal, J. J.;
Gosset, E.; Guy, L. P.; Halbwachs, J. -L.; Hambly, N. C.; Harrison,
D. L.; Hestroffer, D.; Hodgkin, S. T.; Hutton, A.; Jasniewicz, G.;
Jean-Antoine-Piccolo, A.; Jordan, S.; Korn, A. J.; Krone-Martins, A.;
Lanzafame, A. C.; Lebzelter, T.; Löffler, W.; Manteiga, M.; Marrese,
P. M.; Martín-Fleitas, J. M.; Moitinho, A.; Mora, A.; Muinonen, K.;
Osinde, J.; Pancino, E.; Pauwels, T.; Petit, J. -M.; Recio-Blanco, A.;
Richards, P. J.; Rimoldini, L.; Robin, A. C.; Sarro, L. M.; Siopis,
C.; Smith, M.; Sozzetti, A.; Süveges, M.; Torra, J.; van Reeven,
W.; Abbas, U.; Abreu Aramburu, A.; Accart, S.; Aerts, C.; Altavilla,
G.; Álvarez, M. A.; Alvarez, R.; Alves, J.; Anderson, R. I.; Anglada
Varela, E.; Antiche, E.; Antoja, T.; Arcay, B.; Astraatmadja, T. L.;
Bach, N.; Baker, S. G.; Balaguer-Núñez, L.; Balm, P.; Barata, C.;
Barbato, D.; Barblan, F.; Barklem, P. S.; Barrado, D.; Barros, M.;
Barstow, M. A.; Bartholomé Muñoz, L.; Bassilana, J. -L.; Becciani,
U.; Bellazzini, M.; Berihuete, A.; Bertone, S.; Bianchi, L.; Bienaymé,
O.; Blanco-Cuaresma, S.; Boch, T.; Boeche, C.; Borrachero, R.;
Bossini, D.; Bouquillon, S.; Bragaglia, A.; Bramante, L.; Breddels,
M. A.; Bressan, A.; Brouillet, N.; Brüsemeister, T.; Brugaletta, E.;
Bucciarelli, B.; Burlacu, A.; Busonero, D.; Butkevich, A. G.; Buzzi,
R.; Caffau, E.; Cancelliere, R.; Cannizzaro, G.; Cantat-Gaudin,
T.; Carballo, R.; Carlucci, T.; Carrasco, J. M.; Casamiquela, L.;
Castellani, M.; Castro-Ginard, A.; Chemin, L.; Chiavassa, A.; Cocozza,
G.; Costigan, G.; Cowell, S.; Crifo, F.; Crosta, M.; Crowley, C.;
Cuypers, J.; Dafonte, C.; Damerdji, Y.; Dapergolas, A.; David, P.;
David, M.; de Laverny, P.; De Luise, F.; De March, R.; de Souza, R.;
de Torres, A.; Debosscher, J.; del Pozo, E.; Delbo, M.; Delgado, A.;
Delgado, H. E.; Diakite, S.; Diener, C.; Distefano, E.; Dolding, C.;
Drazinos, P.; Durán, J.; Edvardsson, B.; Enke, H.; Eriksson, K.;
Esquej, P.; Eynard Bontemps, G.; Fabre, C.; Fabrizio, M.; Faigler,
S.; Falcão, A. J.; Farràs Casas, M.; Federici, L.; Fedorets, G.;
Fernique, P.; Figueras, F.; Filippi, F.; Findeisen, K.; Fonti, A.;
Fraile, E.; Fraser, M.; Frézouls, B.; Gai, M.; Galleti, S.; Garabato,
D.; García-Sedano, F.; Garofalo, A.; Garralda, N.; Gavel, A.; Gavras,
P.; Gerssen, J.; Giacobbe, P.; Gilmore, G.; Girona, S.; Giuffrida, G.;
Glass, F.; Gomes, M.; Granvik, M.; Gueguen, A.; Guerrier, A.; Guiraud,
J.; Gutié, R.; Haigron, R.; Hatzidimitriou, D.; Hauser, M.; Haywood,
M.; Heiter, U.; Helmi, A.; Heu, J.; Hofmann, W.; Holland, G.; Huckle,
H. E.; Hypki, A.; Icardi, V.; Janßen, K.; Jevardat de Fombelle, G.;
Jonker, P. G.; Juhász, A. L.; Julbe, F.; Karampelas, A.; Kewley,
A.; Klar, J.; Kochoska, A.; Kohley, R.; Kolenberg, K.; Kontizas, M.;
Kontizas, E.; Koposov, S. E.; Kordopatis, G.; Kostrzewa-Rutkowska,
Z.; Koubsky, P.; Lanza, A. F.; Lasne, Y.; Lavigne, J. -B.; Le Fustec,
Y.; Le Poncin-Lafitte, C.; Lebreton, Y.; Leccia, S.; Leclerc, N.;
Lecoeur-Taibi, I.; Lenhardt, H.; Leroux, F.; Liao, S.; Licata, E.;
Lindstrøm, H. E. P.; Lister, T. A.; Livanou, E.; Lobel, A.; López,
M.; Managau, S.; Mann, R. G.; Mantelet, G.; Marchal, O.; Marchant,
J. M.; Marconi, M.; Marinoni, S.; Marschalkó, G.; Marshall, D. J.;
Martino, M.; Marton, G.; Mary, N.; Massari, D.; Matijevič, G.;
Mazeh, T.; McMillan, P. J.; Messina, S.; Millar, N. R.; Molina, D.;
Molinaro, R.; Molnár, L.; Montegriffo, P.; Mor, R.; Morbidelli,
R.; Morel, T.; Morris, D.; Mulone, A. F.; Muraveva, T.; Musella, I.;
Nelemans, G.; Nicastro, L.; Noval, L.; O'Mullane, W.; Ordénovic, C.;
Ordóñez-Blanco, D.; Osborne, P.; Pagani, C.; Pagano, I.; Pailler,
F.; Palacin, H.; Palaversa, L.; Panahi, A.; Pawlak, M.; Piersimoni,
A. M.; Pineau, F. -X.; Plachy, E.; Plum, G.; Poggio, E.; Poujoulet,
E.; Prša, A.; Pulone, L.; Racero, E.; Ragaini, S.; Rambaux, N.;
Regibo, S.; Reylé, C.; Riclet, F.; Ripepi, V.; Riva, A.; Rivard,
A.; Rixon, G.; Roegiers, T.; Roelens, M.; Romero-Gómez, M.; Rowell,
N.; Royer, F.; Ruiz-Dern, L.; Sadowski, G.; Sagristà Sellés, T.;
Sahlmann, J.; Salgado, J.; Salguero, E.; Sanna, N.; Santana-Ros, T.;
Sarasso, M.; Savietto, H.; Schultheis, M.; Sciacca, E.; Segol, M.;
Segovia, J. C.; Ségransan, D.; Shih, I. -C.; Siltala, L.; Silva,
A. F.; Smart, R. L.; Smith, K. W.; Solano, E.; Solitro, F.; Sordo,
R.; Soria Nieto, S.; Souchay, J.; Spagna, A.; Spoto, F.; Stampa, U.;
Steele, I. A.; Stephenson, C. A.; Stoev, H.; Suess, F. F.; Surdej,
J.; Szabados, L.; Szegedi-Elek, E.; Tapiador, D.; Taris, F.; Tauran,
G.; Taylor, M. B.; Teixeira, R.; Terrett, D.; Teyssandier, P.;
Thuillot, W.; Titarenko, A.; Torra Clotet, F.; Turon, C.; Ulla,
A.; Utrilla, E.; Uzzi, S.; Vaillant, M.; Valentini, G.; Valette,
V.; van Elteren, A.; Van Hemelryck, E.; van Leeuwen, M.; Vaschetto,
M.; Vecchiato, A.; Veljanoski, J.; Viala, Y.; Vicente, D.; Vogt, S.;
von Essen, C.; Voss, H.; Votruba, V.; Voutsinas, S.; Walmsley, G.;
Weiler, M.; Wertz, O.; Wevers, T.; Wyrzykowski, Ł.; Yoldas, A.;
Žerjal, M.; Ziaeepour, H.; Zorec, J.; Zschocke, S.; Zucker, S.;
Zurbach, C.; Zwitter, T.
Bibcode: 2018A&A...616A..14G
Altcode: 2018arXiv180409377M
Context. The second release of Gaia data (Gaia DR2) contains the
astrometric parameters for more than half a million quasars. This set
defines a kinematically non-rotating reference frame in the optical
domain. A subset of these quasars have accurate VLBI positions
that allow the axes of the reference frame to be aligned with the
International Celestial Reference System (ICRF) radio frame.
Aims: We describe the astrometric and photometric properties of
the quasars that were selected to represent the celestial reference
frame of Gaia DR2 (Gaia-CRF2), and to compare the optical and radio
positions for sources with accurate VLBI positions.
Methods:
Descriptive statistics are used to characterise the overall properties
of the quasar sample. Residual rotation and orientation errors and
large-scale systematics are quantified by means of expansions in vector
spherical harmonics. Positional differences are calculated relative to
a prototype version of the forthcoming ICRF3.
Results: Gaia-CRF2
consists of the positions of a sample of 556 869 sources in Gaia DR2,
obtained from a positional cross-match with the ICRF3-prototype and
AllWISE AGN catalogues. The sample constitutes a clean, dense, and
homogeneous set of extragalactic point sources in the magnitude range
G ≃ 16 to 21 mag with accurately known optical positions. The median
positional uncertainty is 0.12 mas for G < 18 mag and 0.5 mas at
G = mag. Large-scale systematics are estimated to be in the range 20
to 30 μas. The accuracy claims are supported by the parallaxes and
proper motions of the quasars in Gaia DR2. The optical positions for
a subset of 2820 sources in common with the ICRF3-prototype show very
good overall agreement with the radio positions, but several tens of
sources have significantly discrepant positions.
Conclusions:
Based on less than 40% of the data expected from the nominal Gaia
mission, Gaia-CRF2 is the first realisation of a non-rotating global
optical reference frame that meets the ICRS prescriptions, meaning
that it is built only on extragalactic sources. Its accuracy matches
the current radio frame of the ICRF, but the density of sources in
all parts of the sky is much higher, except along the Galactic equator.
Title: Gaia Data Release 2. Mapping the Milky Way disc kinematics
Authors: Gaia Collaboration; Katz, D.; Antoja, T.; Romero-Gómez, M.;
Drimmel, R.; Reylé, C.; Seabroke, G. M.; Soubiran, C.; Babusiaux,
C.; Di Matteo, P.; Figueras, F.; Poggio, E.; Robin, A. C.; Evans,
D. W.; Brown, A. G. A.; Vallenari, A.; Prusti, T.; de Bruijne,
J. H. J.; Bailer-Jones, C. A. L.; Biermann, M.; Eyer, L.; Jansen,
F.; Jordi, C.; Klioner, S. A.; Lammers, U.; Lindegren, L.; Luri,
X.; Mignard, F.; Panem, C.; Pourbaix, D.; Randich, S.; Sartoretti,
P.; Siddiqui, H. I.; van Leeuwen, F.; Walton, N. A.; Arenou, F.;
Bastian, U.; Cropper, M.; Lattanzi, M. G.; Bakker, J.; Cacciari,
C.; Casta n, J.; Chaoul, L.; Cheek, N.; De Angeli, F.; Fabricius,
C.; Guerra, R.; Holl, B.; Masana, E.; Messineo, R.; Mowlavi, N.;
Nienartowicz, K.; Panuzzo, P.; Portell, J.; Riello, M.; Tanga, P.;
Thévenin, F.; Gracia-Abril, G.; Comoretto, G.; Garcia-Reinaldos, M.;
Teyssier, D.; Altmann, M.; Andrae, R.; Audard, M.; Bellas-Velidis,
I.; Benson, K.; Berthier, J.; Blomme, R.; Burgess, P.; Busso, G.;
Carry, B.; Cellino, A.; Clementini, G.; Clotet, M.; Creevey, O.;
Davidson, M.; De Ridder, J.; Delchambre, L.; Dell'Oro, A.; Ducourant,
C.; Fernández-Hernández, J.; Fouesneau, M.; Frémat, Y.; Galluccio,
L.; García-Torres, M.; González-Núñez, J.; González-Vidal, J. J.;
Gosset, E.; Guy, L. P.; Halbwachs, J. -L.; Hambly, N. C.; Harrison,
D. L.; Hernández, J.; Hestroffer, D.; Hodgkin, S. T.; Hutton, A.;
Jasniewicz, G.; Jean-Antoine-Piccolo, A.; Jordan, S.; Korn, A. J.;
Krone-Martins, A.; Lanzafame, A. C.; Lebzelter, T.; Löffler, W.;
Manteiga, M.; Marrese, P. M.; Martín-Fleitas, J. M.; Moitinho, A.;
Mora, A.; Muinonen, K.; Osinde, J.; Pancino, E.; Pauwels, T.; Petit,
J. -M.; Recio-Blanco, A.; Richards, P. J.; Rimoldini, L.; Sarro,
L. M.; Siopis, C.; Smith, M.; Sozzetti, A.; Süveges, M.; Torra, J.;
van Reeven, W.; Abbas, U.; Abreu Aramburu, A.; Accart, S.; Aerts, C.;
Altavilla, G.; Álvarez, M. A.; Alvarez, R.; Alves, J.; Anderson,
R. I.; Andrei, A. H.; Anglada Varela, E.; Antiche, E.; Arcay, B.;
Astraatmadja, T. L.; Bach, N.; Baker, S. G.; Balaguer-Núñez, L.;
Balm, P.; Barache, C.; Barata, C.; Barbato, D.; Barblan, F.; Barklem,
P. S.; Barrado, D.; Barros, M.; Barstow, M. A.; Bartholomé Muñoz,
L.; Bassilana, J. -L.; Becciani, U.; Bellazzini, M.; Berihuete, A.;
Bertone, S.; Bianchi, L.; Bienaymé, O.; Blanco-Cuaresma, S.; Boch,
T.; Boeche, C.; Bombrun, A.; Borrachero, R.; Bossini, D.; Bouquillon,
S.; Bourda, G.; Bragaglia, A.; Bramante, L.; Breddels, M. A.; Bressan,
A.; Brouillet, N.; Brüsemeister, T.; Brugaletta, E.; Bucciarelli,
B.; Burlacu, A.; Busonero, D.; Butkevich, A. G.; Buzzi, R.; Caffau,
E.; Cancelliere, R.; Cannizzaro, G.; Cantat-Gaudin, T.; Carballo,
R.; Carlucci, T.; Carrasco, J. M.; Casamiquela, L.; Castellani, M.;
Castro-Ginard, A.; Charlot, P.; Chemin, L.; Chiavassa, A.; Cocozza,
G.; Costigan, G.; Cowell, S.; Crifo, F.; Crosta, M.; Crowley, C.;
Cuypers, J.; Dafonte, C.; Damerdji, Y.; Dapergolas, A.; David, P.;
David, M.; de Laverny, P.; De Luise, F.; De March, R.; de Souza, R.;
de Torres, A.; Debosscher, J.; del Pozo, E.; Delbo, M.; Delgado, A.;
Delgado, H. E.; Diakite, S.; Diener, C.; Distefano, E.; Dolding, C.;
Drazinos, P.; Durán, J.; Edvardsson, B.; Enke, H.; Eriksson, K.;
Esquej, P.; Eynard Bontemps, G.; Fabre, C.; Fabrizio, M.; Faigler,
S.; Falc a, A. J.; Farràs Casas, M.; Federici, L.; Fedorets, G.;
Fernique, P.; Filippi, F.; Findeisen, K.; Fonti, A.; Fraile, E.;
Fraser, M.; Frézouls, B.; Gai, M.; Galleti, S.; Garabato, D.;
García-Sedano, F.; Garofalo, A.; Garralda, N.; Gavel, A.; Gavras,
P.; Gerssen, J.; Geyer, R.; Giacobbe, P.; Gilmore, G.; Girona,
S.; Giuffrida, G.; Glass, F.; Gomes, M.; Granvik, M.; Gueguen, A.;
Guerrier, A.; Guiraud, J.; Gutié, R.; Haigron, R.; Hatzidimitriou,
D.; Hauser, M.; Haywood, M.; Heiter, U.; Helmi, A.; Heu, J.; Hilger,
T.; Hobbs, D.; Hofmann, W.; Holland, G.; Huckle, H. E.; Hypki, A.;
Icardi, V.; Janßen, K.; Jevardat de Fombelle, G.; Jonker, P. G.;
Juhász, Á. L.; Julbe, F.; Karampelas, A.; Kewley, A.; Klar, J.;
Kochoska, A.; Kohley, R.; Kolenberg, K.; Kontizas, M.; Kontizas, E.;
Koposov, S. E.; Kordopatis, G.; Kostrzewa-Rutkowska, Z.; Koubsky, P.;
Lambert, S.; Lanza, A. F.; Lasne, Y.; Lavigne, J. -B.; Le Fustec,
Y.; Le Poncin-Lafitte, C.; Lebreton, Y.; Leccia, S.; Leclerc, N.;
Lecoeur-Taibi, I.; Lenhardt, H.; Leroux, F.; Liao, S.; Licata, E.;
Lindstrøm, H. E. P.; Lister, T. A.; Livanou, E.; Lobel, A.; López,
M.; Managau, S.; Mann, R. G.; Mantelet, G.; Marchal, O.; Marchant,
J. M.; Marconi, M.; Marinoni, S.; Marschalkó, G.; Marshall, D. J.;
Martino, M.; Marton, G.; Mary, N.; Massari, D.; Matijevič, G.; Mazeh,
T.; McMillan, P. J.; Messina, S.; Michalik, D.; Millar, N. R.; Molina,
D.; Molinaro, R.; Molnár, L.; Montegriffo, P.; Mor, R.; Morbidelli,
R.; Morel, T.; Morris, D.; Mulone, A. F.; Muraveva, T.; Musella, I.;
Nelemans, G.; Nicastro, L.; Noval, L.; O'Mullane, W.; Ordénovic, C.;
Ordóñez-Blanco, D.; Osborne, P.; Pagani, C.; Pagano, I.; Pailler,
F.; Palacin, H.; Palaversa, L.; Panahi, A.; Pawlak, M.; Piersimoni,
A. M.; Pineau, F. -X.; Plachy, E.; Plum, G.; Poujoulet, E.; Prša,
A.; Pulone, L.; Racero, E.; Ragaini, S.; Rambaux, N.; Ramos-Lerate,
M.; Regibo, S.; Riclet, F.; Ripepi, V.; Riva, A.; Rivard, A.; Rixon,
G.; Roegiers, T.; Roelens, M.; Rowell, N.; Royer, F.; Ruiz-Dern,
L.; Sadowski, G.; Sagristà Sellés, T.; Sahlmann, J.; Salgado, J.;
Salguero, E.; Sanna, N.; Santana-Ros, T.; Sarasso, M.; Savietto, H.;
Schultheis, M.; Sciacca, E.; Segol, M.; Segovia, J. C.; Ségransan,
D.; Shih, I. -C.; Siltala, L.; Silva, A. F.; Smart, R. L.; Smith,
K. W.; Solano, E.; Solitro, F.; Sordo, R.; Soria Nieto, S.; Souchay,
J.; Spagna, A.; Spoto, F.; Stampa, U.; Steele, I. A.; Steidelmüller,
H.; Stephenson, C. A.; Stoev, H.; Suess, F. F.; Surdej, J.; Szabados,
L.; Szegedi-Elek, E.; Tapiador, D.; Taris, F.; Tauran, G.; Taylor,
M. B.; Teixeira, R.; Terrett, D.; Teyssandier, P.; Thuillot, W.;
Titarenko, A.; Torra Clotet, F.; Turon, C.; Ulla, A.; Utrilla, E.;
Uzzi, S.; Vaillant, M.; Valentini, G.; Valette, V.; van Elteren,
A.; Van Hemelryck, E.; van Leeuwen, M.; Vaschetto, M.; Vecchiato,
A.; Veljanoski, J.; Viala, Y.; Vicente, D.; Vogt, S.; von Essen, C.;
Voss, H.; Votruba, V.; Voutsinas, S.; Walmsley, G.; Weiler, M.; Wertz,
O.; Wevers, T.; Wyrzykowski, Ł.; Yoldas, A.; Žerjal, M.; Ziaeepour,
H.; Zorec, J.; Zschocke, S.; Zucker, S.; Zurbach, C.; Zwitter, T.
Bibcode: 2018A&A...616A..11G
Altcode: 2018arXiv180409380G
Context. The second Gaia data release (Gaia DR2) contains high-precision
positions, parallaxes, and proper motions for 1.3 billion sources as
well as line-of-sight velocities for 7.2 million stars brighter than
GRVS = 12 mag. Both samples provide a full sky coverage.
Aims: To illustrate the potential of Gaia DR2, we provide a first
look at the kinematics of the Milky Way disc, within a radius of several
kiloparsecs around the Sun.
Methods: We benefit for the first
time from a sample of 6.4 million F-G-K stars with full 6D phase-space
coordinates, precise parallaxes (σϖ/ϖ ≤ 20%), and
precise Galactic cylindrical velocities (median uncertainties of 0.9-1.4
km s-1 and 20% of the stars with uncertainties smaller than
1 km s-1 on all three components). From this sample, we
extracted a sub-sample of 3.2 million giant stars to map the velocity
field of the Galactic disc from 5 kpc to 13 kpc from the Galactic
centre and up to 2 kpc above and below the plane. We also study the
distribution of 0.3 million solar neighbourhood stars (r < 200 pc),
with median velocity uncertainties of 0.4 km s-1, in velocity
space and use the full sample to examine how the over-densities evolve
in more distant regions.
Results: Gaia DR2 allows us to draw 3D
maps of the Galactocentric median velocities and velocity dispersions
with unprecedented accuracy, precision, and spatial resolution. The
maps show the complexity and richness of the velocity field of the
galactic disc. We observe streaming motions in all the components of
the velocities as well as patterns in the velocity dispersions. For
example, we confirm the previously reported negative and positive
galactocentric radial velocity gradients in the inner and outer disc,
respectively. Here, we see them as part of a non-axisymmetric kinematic
oscillation, and we map its azimuthal and vertical behaviour. We also
witness a new global arrangement of stars in the velocity plane of
the solar neighbourhood and in distant regions in which stars are
organised in thin substructures with the shape of circular arches
that are oriented approximately along the horizontal direction in the
U - V plane. Moreover, in distant regions, we see variations in the
velocity substructures more clearly than ever before, in particular,
variations in the velocity of the Hercules stream.
Conclusions:
Gaia DR2 provides the largest existing full 6D phase-space coordinates
catalogue. It also vastly increases the number of available distances
and transverse velocities with respect to Gaia DR1. Gaia DR2 offers
a great wealth of information on the Milky Way and reveals clear
non-axisymmetric kinematic signatures within the Galactic disc, for
instance. It is now up to the astronomical community to explore its
full potential.
Title: Gaia Data Release 2. Observational Hertzsprung-Russell diagrams
Authors: Gaia Collaboration; Babusiaux, C.; van Leeuwen, F.;
Barstow, M. A.; Jordi, C.; Vallenari, A.; Bossini, D.; Bressan,
A.; Cantat-Gaudin, T.; van Leeuwen, M.; Brown, A. G. A.; Prusti,
T.; de Bruijne, J. H. J.; Bailer-Jones, C. A. L.; Biermann, M.;
Evans, D. W.; Eyer, L.; Jansen, F.; Klioner, S. A.; Lammers, U.;
Lindegren, L.; Luri, X.; Mignard, F.; Panem, C.; Pourbaix, D.;
Randich, S.; Sartoretti, P.; Siddiqui, H. I.; Soubiran, C.; Walton,
N. A.; Arenou, F.; Bastian, U.; Cropper, M.; Drimmel, R.; Katz, D.;
Lattanzi, M. G.; Bakker, J.; Cacciari, C.; Castañeda, J.; Chaoul,
L.; Cheek, N.; De Angeli, F.; Fabricius, C.; Guerra, R.; Holl, B.;
Masana, E.; Messineo, R.; Mowlavi, N.; Nienartowicz, K.; Panuzzo,
P.; Portell, J.; Riello, M.; Seabroke, G. M.; Tanga, P.; Thévenin,
F.; Gracia-Abril, G.; Comoretto, G.; Garcia-Reinaldos, M.; Teyssier,
D.; Altmann, M.; Andrae, R.; Audard, M.; Bellas-Velidis, I.; Benson,
K.; Berthier, J.; Blomme, R.; Burgess, P.; Busso, G.; Carry, B.;
Cellino, A.; Clementini, G.; Clotet, M.; Creevey, O.; Davidson,
M.; De Ridder, J.; Delchambre, L.; Dell'Oro, A.; Ducourant, C.;
Fernández-Hernández, J.; Fouesneau, M.; Frémat, Y.; Galluccio, L.;
García-Torres, M.; González-Núñez, J.; González-Vidal, J. J.;
Gosset, E.; Guy, L. P.; Halbwachs, J. -L.; Hambly, N. C.; Harrison,
D. L.; Hernández, J.; Hestroffer, D.; Hodgkin, S. T.; Hutton, A.;
Jasniewicz, G.; Jean-Antoine-Piccolo, A.; Jordan, S.; Korn, A. J.;
Krone-Martins, A.; Lanzafame, A. C.; Lebzelter, T.; Löffler, W.;
Manteiga, M.; Marrese, P. M.; Martín-Fleitas, J. M.; Moitinho, A.;
Mora, A.; Muinonen, K.; Osinde, J.; Pancino, E.; Pauwels, T.; Petit,
J. -M.; Recio-Blanco, A.; Richards, P. J.; Rimoldini, L.; Robin,
A. C.; Sarro, L. M.; Siopis, C.; Smith, M.; Sozzetti, A.; Süveges,
M.; Torra, J.; van Reeven, W.; Abbas, U.; Abreu Aramburu, A.; Accart,
S.; Aerts, C.; Altavilla, G.; Álvarez, M. A.; Alvarez, R.; Alves,
J.; Anderson, R. I.; Andrei, A. H.; Anglada Varela, E.; Antiche, E.;
Antoja, T.; Arcay, B.; Astraatmadja, T. L.; Bach, N.; Baker, S. G.;
Balaguer-Núñez, L.; Balm, P.; Barache, C.; Barata, C.; Barbato,
D.; Barblan, F.; Barklem, P. S.; Barrado, D.; Barros, M.; Bartholomé
Muñoz, L.; Bassilana, J. -L.; Becciani, U.; Bellazzini, M.; Berihuete,
A.; Bertone, S.; Bianchi, L.; Bienaymé, O.; Blanco-Cuaresma, S.;
Boch, T.; Boeche, C.; Bombrun, A.; Borrachero, R.; Bouquillon, S.;
Bourda, G.; Bragaglia, A.; Bramante, L.; Breddels, M. A.; Brouillet,
N.; Brüsemeister, T.; Brugaletta, E.; Bucciarelli, B.; Burlacu, A.;
Busonero, D.; Butkevich, A. G.; Buzzi, R.; Caffau, E.; Cancelliere,
R.; Cannizzaro, G.; Carballo, R.; Carlucci, T.; Carrasco, J. M.;
Casamiquela, L.; Castellani, M.; Castro-Ginard, A.; Charlot, P.;
Chemin, L.; Chiavassa, A.; Cocozza, G.; Costigan, G.; Cowell,
S.; Crifo, F.; Crosta, M.; Crowley, C.; Cuypers, J.; Dafonte, C.;
Damerdji, Y.; Dapergolas, A.; David, P.; David, M.; de Laverny, P.;
De Luise, F.; De March, R.; de Martino, D.; de Souza, R.; de Torres,
A.; Debosscher, J.; del Pozo, E.; Delbo, M.; Delgado, A.; Delgado,
H. E.; Diakite, S.; Diener, C.; Distefano, E.; Dolding, C.; Drazinos,
P.; Durán, J.; Edvardsson, B.; Enke, H.; Eriksson, K.; Esquej, P.;
Eynard Bontemps, G.; Fabre, C.; Fabrizio, M.; Faigler, S.; Falcão,
A. J.; Farràs Casas, M.; Federici, L.; Fedorets, G.; Fernique,
P.; Figueras, F.; Filippi, F.; Findeisen, K.; Fonti, A.; Fraile,
E.; Fraser, M.; Frézouls, B.; Gai, M.; Galleti, S.; Garabato, D.;
García-Sedano, F.; Garofalo, A.; Garralda, N.; Gavel, A.; Gavras,
P.; Gerssen, J.; Geyer, R.; Giacobbe, P.; Gilmore, G.; Girona,
S.; Giuffrida, G.; Glass, F.; Gomes, M.; Granvik, M.; Gueguen, A.;
Guerrier, A.; Guiraud, J.; Gutié, R.; Haigron, R.; Hatzidimitriou,
D.; Hauser, M.; Haywood, M.; Heiter, U.; Helmi, A.; Heu, J.; Hilger,
T.; Hobbs, D.; Hofmann, W.; Holland, G.; Huckle, H. E.; Hypki, A.;
Icardi, V.; Janßen, K.; Jevardat de Fombelle, G.; Jonker, P. G.;
Juhász, Á. L.; Julbe, F.; Karampelas, A.; Kewley, A.; Klar, J.;
Kochoska, A.; Kohley, R.; Kolenberg, K.; Kontizas, M.; Kontizas, E.;
Koposov, S. E.; Kordopatis, G.; Kostrzewa-Rutkowska, Z.; Koubsky, P.;
Lambert, S.; Lanza, A. F.; Lasne, Y.; Lavigne, J. -B.; Le Fustec,
Y.; Le Poncin-Lafitte, C.; Lebreton, Y.; Leccia, S.; Leclerc, N.;
Lecoeur-Taibi, I.; Lenhardt, H.; Leroux, F.; Liao, S.; Licata, E.;
Lindstrøm, H. E. P.; Lister, T. A.; Livanou, E.; Lobel, A.; López,
M.; Managau, S.; Mann, R. G.; Mantelet, G.; Marchal, O.; Marchant,
J. M.; Marconi, M.; Marinoni, S.; Marschalkó, G.; Marshall, D. J.;
Martino, M.; Marton, G.; Mary, N.; Massari, D.; Matijevič, G.; Mazeh,
T.; McMillan, P. J.; Messina, S.; Michalik, D.; Millar, N. R.; Molina,
D.; Molinaro, R.; Molnár, L.; Montegriffo, P.; Mor, R.; Morbidelli,
R.; Morel, T.; Morris, D.; Mulone, A. F.; Muraveva, T.; Musella, I.;
Nelemans, G.; Nicastro, L.; Noval, L.; O'Mullane, W.; Ordénovic, C.;
Ordóñez-Blanco, D.; Osborne, P.; Pagani, C.; Pagano, I.; Pailler, F.;
Palacin, H.; Palaversa, L.; Panahi, A.; Pawlak, M.; Piersimoni, A. M.;
Pineau, F. -X.; Plachy, E.; Plum, G.; Poggio, E.; Poujoulet, E.; Prša,
A.; Pulone, L.; Racero, E.; Ragaini, S.; Rambaux, N.; Ramos-Lerate,
M.; Regibo, S.; Reylé, C.; Riclet, F.; Ripepi, V.; Riva, A.; Rivard,
A.; Rixon, G.; Roegiers, T.; Roelens, M.; Romero-Gómez, M.; Rowell,
N.; Royer, F.; Ruiz-Dern, L.; Sadowski, G.; Sagristà Sellés, T.;
Sahlmann, J.; Salgado, J.; Salguero, E.; Sanna, N.; Santana-Ros, T.;
Sarasso, M.; Savietto, H.; Schultheis, M.; Sciacca, E.; Segol, M.;
Segovia, J. C.; Ségransan, D.; Shih, I. -C.; Siltala, L.; Silva,
A. F.; Smart, R. L.; Smith, K. W.; Solano, E.; Solitro, F.; Sordo,
R.; Soria Nieto, S.; Souchay, J.; Spagna, A.; Spoto, F.; Stampa,
U.; Steele, I. A.; Steidelmüller, H.; Stephenson, C. A.; Stoev, H.;
Suess, F. F.; Surdej, J.; Szabados, L.; Szegedi-Elek, E.; Tapiador,
D.; Taris, F.; Tauran, G.; Taylor, M. B.; Teixeira, R.; Terrett,
D.; Teyssandier, P.; Thuillot, W.; Titarenko, A.; Torra Clotet, F.;
Turon, C.; Ulla, A.; Utrilla, E.; Uzzi, S.; Vaillant, M.; Valentini,
G.; Valette, V.; van Elteren, A.; Van Hemelryck, E.; Vaschetto, M.;
Vecchiato, A.; Veljanoski, J.; Viala, Y.; Vicente, D.; Vogt, S.;
von Essen, C.; Voss, H.; Votruba, V.; Voutsinas, S.; Walmsley, G.;
Weiler, M.; Wertz, O.; Wevers, T.; Wyrzykowski, Ł.; Yoldas, A.;
Žerjal, M.; Ziaeepour, H.; Zorec, J.; Zschocke, S.; Zucker, S.;
Zurbach, C.; Zwitter, T.
Bibcode: 2018A&A...616A..10G
Altcode: 2018arXiv180409378G
Context. Gaia Data Release 2 provides high-precision astrometry and
three-band photometry for about 1.3 billion sources over the full
sky. The precision, accuracy, and homogeneity of both astrometry and
photometry are unprecedented.
Aims: We highlight the power of
the Gaia DR2 in studying many fine structures of the Hertzsprung-Russell
diagram (HRD). Gaia allows us to present many different HRDs, depending
in particular on stellar population selections. We do not aim here
for completeness in terms of types of stars or stellar evolutionary
aspects. Instead, we have chosen several illustrative examples.
Methods: We describe some of the selections that can be made in Gaia
DR2 to highlight the main structures of the Gaia HRDs. We select both
field and cluster (open and globular) stars, compare the observations
with previous classifications and with stellar evolutionary tracks,
and we present variations of the Gaia HRD with age, metallicity, and
kinematics. Late stages of stellar evolution such as hot subdwarfs,
post-AGB stars, planetary nebulae, and white dwarfs are also analysed,
as well as low-mass brown dwarf objects.
Results: The Gaia HRDs
are unprecedented in both precision and coverage of the various Milky
Way stellar populations and stellar evolutionary phases. Many fine
structures of the HRDs are presented. The clear split of the white
dwarf sequence into hydrogen and helium white dwarfs is presented
for the first time in an HRD. The relation between kinematics and the
HRD is nicely illustrated. Two different populations in a classical
kinematic selection of the halo are unambiguously identified in the
HRD. Membership and mean parameters for a selected list of open
clusters are provided. They allow drawing very detailed cluster
sequences, highlighting fine structures, and providing extremely
precise empirical isochrones that will lead to more insight in
stellar physics.
Conclusions: Gaia DR2 demonstrates the
potential of combining precise astrometry and photometry for large
samples for studies in stellar evolution and stellar population
and opens an entire new area for HRD-based studies. The full
Table A.1 is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/616/A10
Title: Gaia Data Release 2. The astrometric solution
Authors: Lindegren, L.; Hernández, J.; Bombrun, A.; Klioner, S.;
Bastian, U.; Ramos-Lerate, M.; de Torres, A.; Steidelmüller, H.;
Stephenson, C.; Hobbs, D.; Lammers, U.; Biermann, M.; Geyer, R.;
Hilger, T.; Michalik, D.; Stampa, U.; McMillan, P. J.; Castañeda,
J.; Clotet, M.; Comoretto, G.; Davidson, M.; Fabricius, C.; Gracia,
G.; Hambly, N. C.; Hutton, A.; Mora, A.; Portell, J.; van Leeuwen,
F.; Abbas, U.; Abreu, A.; Altmann, M.; Andrei, A.; Anglada, E.;
Balaguer-Núñez, L.; Barache, C.; Becciani, U.; Bertone, S.; Bianchi,
L.; Bouquillon, S.; Bourda, G.; Brüsemeister, T.; Bucciarelli, B.;
Busonero, D.; Buzzi, R.; Cancelliere, R.; Carlucci, T.; Charlot, P.;
Cheek, N.; Crosta, M.; Crowley, C.; de Bruijne, J.; de Felice, F.;
Drimmel, R.; Esquej, P.; Fienga, A.; Fraile, E.; Gai, M.; Garralda,
N.; González-Vidal, J. J.; Guerra, R.; Hauser, M.; Hofmann, W.;
Holl, B.; Jordan, S.; Lattanzi, M. G.; Lenhardt, H.; Liao, S.;
Licata, E.; Lister, T.; Löffler, W.; Marchant, J.; Martin-Fleitas,
J. -M.; Messineo, R.; Mignard, F.; Morbidelli, R.; Poggio, E.; Riva,
A.; Rowell, N.; Salguero, E.; Sarasso, M.; Sciacca, E.; Siddiqui,
H.; Smart, R. L.; Spagna, A.; Steele, I.; Taris, F.; Torra, J.;
van Elteren, A.; van Reeven, W.; Vecchiato, A.
Bibcode: 2018A&A...616A...2L
Altcode: 2018arXiv180409366L
Context. Gaia Data Release 2 (Gaia DR2) contains results for 1693
million sources in the magnitude range 3 to 21 based on observations
collected by the European Space Agency Gaia satellite during the
first 22 months of its operational phase.
Aims: We describe the
input data, models, and processing used for the astrometric content
of Gaia DR2, and the validation of these resultsperformed within the
astrometry task.
Methods: Some 320 billion centroid positions
from the pre-processed astrometric CCD observations were used to
estimate the five astrometric parameters (positions, parallaxes, and
proper motions) for 1332 million sources, and approximate positions
at the reference epoch J2015.5 for an additional 361 million mostly
faint sources. These data were calculated in two steps. First, the
satellite attitude and the astrometric calibration parameters of the
CCDs were obtained in an astrometric global iterative solution for
16 million selected sources, using about 1% of the input data. This
primary solution was tied to the extragalactic International Celestial
Reference System (ICRS) by means of quasars. The resulting attitude and
calibration were then used to calculate the astrometric parameters of
all the sources. Special validation solutions were used to characterise
the random and systematic errors in parallax and proper motion.
Results: For the sources with five-parameter astrometric solutions,
the median uncertainty in parallax and position at the reference
epoch J2015.5 is about 0.04 mas for bright (G < 14 mag) sources,
0.1 mas at G = 17 mag, and 0.7 masat G = 20 mag. In the proper motion
components the corresponding uncertainties are 0.05, 0.2, and 1.2
mas yr-1, respectively.The optical reference frame defined
by Gaia DR2 is aligned with ICRS and is non-rotating with respect to
the quasars to within 0.15 mas yr-1. From the quasars and
validation solutions we estimate that systematics in the parallaxes
depending on position, magnitude, and colour are generally below
0.1 mas, but the parallaxes are on the whole too small by about 0.03
mas. Significant spatial correlations of up to 0.04 mas in parallax
and 0.07 mas yr-1 in proper motion are seen on small (<
1 deg) and intermediate (20 deg) angular scales. Important statistics
and information for the users of the Gaia DR2 astrometry are given in
the appendices.
Title: Gaia Data Release 2. Kinematics of globular clusters and
dwarf galaxies around the Milky Way
Authors: Gaia Collaboration; Helmi, A.; van Leeuwen, F.; McMillan,
P. J.; Massari, D.; Antoja, T.; Robin, A. C.; Lindegren, L.;
Bastian, U.; Arenou, F.; Babusiaux, C.; Biermann, M.; Breddels,
M. A.; Hobbs, D.; Jordi, C.; Pancino, E.; Reylé, C.; Veljanoski,
J.; Brown, A. G. A.; Vallenari, A.; Prusti, T.; de Bruijne,
J. H. J.; Bailer-Jones, C. A. L.; Evans, D. W.; Eyer, L.; Jansen,
F.; Klioner, S. A.; Lammers, U.; Luri, X.; Mignard, F.; Panem,
C.; Pourbaix, D.; Randich, S.; Sartoretti, P.; Siddiqui, H. I.;
Soubiran, C.; Walton, N. A.; Cropper, M.; Drimmel, R.; Katz, D.;
Lattanzi, M. G.; Bakker, J.; Cacciari, C.; Castañeda, J.; Chaoul,
L.; Cheek, N.; De Angeli, F.; Fabricius, C.; Guerra, R.; Holl, B.;
Masana, E.; Messineo, R.; Mowlavi, N.; Nienartowicz, K.; Panuzzo,
P.; Portell, J.; Riello, M.; Seabroke, G. M.; Tanga, P.; Thévenin,
F.; Gracia-Abril, G.; Comoretto, G.; Garcia-Reinaldos, M.; Teyssier,
D.; Altmann, M.; Andrae, R.; Audard, M.; Bellas-Velidis, I.; Benson,
K.; Berthier, J.; Blomme, R.; Burgess, P.; Busso, G.; Carry, B.;
Cellino, A.; Clementini, G.; Clotet, M.; Creevey, O.; Davidson,
M.; De Ridder, J.; Delchambre, L.; Dell'Oro, A.; Ducourant, C.;
Fernández-Hernández, J.; Fouesneau, M.; Frémat, Y.; Galluccio, L.;
García-Torres, M.; González-Núñez, J.; González-Vidal, J. J.;
Gosset, E.; Guy, L. P.; Halbwachs, J. -L.; Hambly, N. C.; Harrison,
D. L.; Hernández, J.; Hestroffer, D.; Hodgkin, S. T.; Hutton, A.;
Jasniewicz, G.; Jean-Antoine-Piccolo, A.; Jordan, S.; Korn, A. J.;
Krone-Martins, A.; Lanzafame, A. C.; Lebzelter, T.; Löffler, W.;
Manteiga, M.; Marrese, P. M.; Martín-Fleitas, J. M.; Moitinho, A.;
Mora, A.; Muinonen, K.; Osinde, J.; Pauwels, T.; Petit, J. -M.;
Recio-Blanco, A.; Richards, P. J.; Rimoldini, L.; Sarro, L. M.;
Siopis, C.; Smith, M.; Sozzetti, A.; Süveges, M.; Torra, J.; van
Reeven, W.; Abbas, U.; Abreu Aramburu, A.; Accart, S.; Aerts, C.;
Altavilla, G.; Álvarez, M. A.; Alvarez, R.; Alves, J.; Anderson,
R. I.; Andrei, A. H.; Anglada Varela, E.; Antiche, E.; Arcay, B.;
Astraatmadja, T. L.; Bach, N.; Baker, S. G.; Balaguer-Núñez, L.;
Balm, P.; Barache, C.; Barata, C.; Barbato, D.; Barblan, F.; Barklem,
P. S.; Barrado, D.; Barros, M.; Barstow, M. A.; Bartholomé Muñoz,
S.; Bassilana, J. -L.; Becciani, U.; Bellazzini, M.; Berihuete, A.;
Bertone, S.; Bianchi, L.; Bienaymé, O.; Blanco-Cuaresma, S.; Boch,
T.; Boeche, C.; Bombrun, A.; Borrachero, R.; Bossini, D.; Bouquillon,
S.; Bourda, G.; Bragaglia, A.; Bramante, L.; Bressan, A.; Brouillet,
N.; Brüsemeister, T.; Brugaletta, E.; Bucciarelli, B.; Burlacu, A.;
Busonero, D.; Butkevich, A. G.; Buzzi, R.; Caffau, E.; Cancelliere,
R.; Cannizzaro, G.; Cantat-Gaudin, T.; Carballo, R.; Carlucci, T.;
Carrasco, J. M.; Casamiquela, L.; Castellani, M.; Castro-Ginard, A.;
Charlot, P.; Chemin, L.; Chiavassa, A.; Cocozza, G.; Costigan, G.;
Cowell, S.; Crifo, F.; Crosta, M.; Crowley, C.; Cuypers, J.; Dafonte,
C.; Damerdji, Y.; Dapergolas, A.; David, P.; David, M.; de Laverny,
P.; De Luise, F.; De March, R.; de Martino, D.; de Souza, R.; de
Torres, A.; Debosscher, J.; del Pozo, E.; Delbo, M.; Delgado, A.;
Delgado, H. E.; Di Matteo, P.; Diakite, S.; Diener, C.; Distefano,
E.; Dolding, C.; Drazinos, P.; Durán, J.; Edvardsson, B.; Enke, H.;
Eriksson, K.; Esquej, P.; Eynard Bontemps, G.; Fabre, C.; Fabrizio,
M.; Faigler, S.; Falcão, A. J.; Farràs Casas, M.; Federici, L.;
Fedorets, G.; Fernique, P.; Figueras, F.; Filippi, F.; Findeisen, K.;
Fonti, A.; Fraile, E.; Fraser, M.; Frézouls, B.; Gai, M.; Galleti, S.;
Garabato, D.; García-Sedano, F.; Garofalo, A.; Garralda, N.; Gavel,
A.; Gavras, P.; Gerssen, J.; Geyer, R.; Giacobbe, P.; Gilmore, G.;
Girona, S.; Giuffrida, G.; Glass, F.; Gomes, M.; Granvik, M.; Gueguen,
A.; Guerrier, A.; Guiraud, J.; Gutiérrez-Sánchez, R.; Hofmann,
W.; Holland, G.; Huckle, H. E.; Hypki, A.; Icardi, V.; Janßen, K.;
Jevardat de Fombelle, G.; Jonker, P. G.; Juhász, Á. L.; Julbe,
F.; Karampelas, A.; Kewley, A.; Klar, J.; Kochoska, A.; Kohley, R.;
Kolenberg, K.; Kontizas, M.; Kontizas, E.; Koposov, S. E.; Kordopatis,
G.; Kostrzewa-Rutkowska, Z.; Koubsky, P.; Lambert, S.; Lanza, A. F.;
Lasne, Y.; Lavigne, J. -B.; Le Fustec, Y.; Le Poncin-Lafitte, C.;
Lebreton, Y.; Leccia, S.; Leclerc, N.; Lecoeur-Taibi, I.; Lenhardt,
H.; Leroux, F.; Liao, S.; Licata, E.; Lindstrøm, H. E. P.; Lister,
T. A.; Livanou, E.; Lobel, A.; López, M.; Managau, S.; Mann, R. G.;
Mantelet, G.; Marchal, O.; Marchant, J. M.; Marconi, M.; Marinoni,
S.; Marschalkó, G.; Marshall, D. J.; Martino, M.; Marton, G.; Mary,
N.; Matijevič, G.; Mazeh, T.; Messina, S.; Michalik, D.; Millar,
N. R.; Molina, D.; Molinaro, R.; Molnár, L.; Montegriffo, P.; Mor,
R.; Morbidelli, R.; Morel, T.; Morris, D.; Mulone, A. F.; Muraveva,
T.; Musella, I.; Nelemans, G.; Nicastro, L.; Noval, L.; O'Mullane, W.;
Ordénovic, C.; Ordóñez-Blanco, D.; Osborne, P.; Pagani, C.; Pagano,
I.; Pailler, F.; Palacin, H.; Palaversa, L.; Panahi, A.; Pawlak, M.;
Piersimoni, A. M.; Pineau, F. -X.; Plachy, E.; Plum, G.; Poggio, E.;
Poujoulet, E.; Prša, A.; Pulone, L.; Racero, E.; Ragaini, S.; Rambaux,
N.; Ramos-Lerate, M.; Regibo, S.; Riclet, F.; Ripepi, V.; Riva, A.;
Rivard, A.; Rixon, G.; Roegiers, T.; Roelens, M.; Romero-Gómez, M.;
Rowell, N.; Royer, F.; Ruiz-Dern, L.; Sadowski, G.; Sagristà Sellés,
T.; Sahlmann, J.; Salgado, J.; Salguero, E.; Sanna, N.; Santana-Ros,
T.; Sarasso, M.; Savietto, H.; Schultheis, M.; Sciacca, E.; Segol,
M.; Segovia, J. C.; Ségransan, D.; Shih, I. -C.; Siltala, L.; Silva,
A. F.; Smart, R. L.; Smith, K. W.; Solano, E.; Solitro, F.; Sordo,
R.; Soria Nieto, S.; Souchay, J.; Spagna, A.; Spoto, F.; Stampa,
U.; Steele, I. A.; Steidelmüller, H.; Stephenson, C. A.; Stoev, H.;
Suess, F. F.; Surdej, J.; Szabados, L.; Szegedi-Elek, E.; Tapiador,
D.; Taris, F.; Tauran, G.; Taylor, M. B.; Teixeira, R.; Terrett, D.;
Teyssandier, P.; Thuillot, W.; Titarenko, A.; Torra Clotet, F.;
Turon, C.; Ulla, A.; Utrilla, E.; Uzzi, S.; Vaillant, M.; Valentini,
G.; Valette, V.; van Elteren, A.; Van Hemelryck, E.; van Leeuwen,
M.; Vaschetto, M.; Vecchiato, A.; Viala, Y.; Vicente, D.; Vogt, S.;
von Essen, C.; Voss, H.; Votruba, V.; Voutsinas, S.; Walmsley, G.;
Weiler, M.; Wertz, O.; Wevems, T.; Wyrzykowski, Ł.; Yoldas, A.;
Žerjal, M.; Ziaeepour, H.; Zorec, J.; Zschocke, S.; Zucker, S.;
Zurbach, C.; Zwitter, T.
Bibcode: 2018A&A...616A..12G
Altcode: 2018arXiv180409381G
Note to the Readers: Following the publication of the corrigendum,
the article was corrected on 15 May 2020. Context.
Aims:
The goal of this paper is to demonstrate the outstanding quality
of the second data release of the Gaia mission and its power for
constraining many different aspects of the dynamics of the satellites
of the Milky Way. We focus here on determining the proper motions of
75 Galactic globular clusters, nine dwarf spheroidal galaxies, one
ultra-faint system, and the Large and Small Magellanic Clouds.
Methods: Using data extracted from the Gaia archive, we derived
the proper motions and parallaxes for these systems, as well as
their uncertainties. We demonstrate that the errors, statistical
and systematic, are relatively well understood. We integrated the
orbits of these objects in three different Galactic potentials, and
characterised their properties. We present the derived proper motions,
space velocities, and characteristic orbital parameters in various
tables to facilitate their use by the astronomical community.
Results: Our limited and straightforward analyses have allowed us
for example to (i) determine absolute and very precise proper motions
for globular clusters; (ii) detect clear rotation signatures in the
proper motions of at least five globular clusters; (iii) show that
the satellites of the Milky Way are all on high-inclination orbits,
but that they do not share a single plane of motion; (iv) derive a lower
limit for the mass of the Milky Way of 9.1-2.6+6.2
× 1011 M⊙ based on the assumption that the Leo
I dwarf spheroidal is bound; (v) derive a rotation curve for the Large
Magellanic Cloud based solely on proper motions that is competitive
with line-of-sight velocity curves, now using many orders of magnitude
more sources; and (vi) unveil the dynamical effect of the bar on the
motions of stars in the Large Magellanic Cloud.
Conclusions: All
these results highlight the incredible power of the Gaia astrometric
mission, and in particular of its second data release. Full
Table D.3 is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/616/A12
Title: Gaia Data Release 2. Summary of the contents and survey
properties
Authors: Gaia Collaboration; Brown, A. G. A.; Vallenari, A.; Prusti,
T.; de Bruijne, J. H. J.; Babusiaux, C.; Bailer-Jones, C. A. L.;
Biermann, M.; Evans, D. W.; Eyer, L.; Jansen, F.; Jordi, C.; Klioner,
S. A.; Lammers, U.; Lindegren, L.; Luri, X.; Mignard, F.; Panem,
C.; Pourbaix, D.; Randich, S.; Sartoretti, P.; Siddiqui, H. I.;
Soubiran, C.; van Leeuwen, F.; Walton, N. A.; Arenou, F.; Bastian,
U.; Cropper, M.; Drimmel, R.; Katz, D.; Lattanzi, M. G.; Bakker,
J.; Cacciari, C.; Castañeda, J.; Chaoul, L.; Cheek, N.; De Angeli,
F.; Fabricius, C.; Guerra, R.; Holl, B.; Masana, E.; Messineo, R.;
Mowlavi, N.; Nienartowicz, K.; Panuzzo, P.; Portell, J.; Riello,
M.; Seabroke, G. M.; Tanga, P.; Thévenin, F.; Gracia-Abril, G.;
Comoretto, G.; Garcia-Reinaldos, M.; Teyssier, D.; Altmann, M.;
Andrae, R.; Audard, M.; Bellas-Velidis, I.; Benson, K.; Berthier,
J.; Blomme, R.; Burgess, P.; Busso, G.; Carry, B.; Cellino, A.;
Clementini, G.; Clotet, M.; Creevey, O.; Davidson, M.; De Ridder, J.;
Delchambre, L.; Dell'Oro, A.; Ducourant, C.; Fernández-Hernández,
J.; Fouesneau, M.; Frémat, Y.; Galluccio, L.; García-Torres,
M.; González-Núñez, J.; González-Vidal, J. J.; Gosset, E.; Guy,
L. P.; Halbwachs, J. -L.; Hambly, N. C.; Harrison, D. L.; Hernández,
J.; Hestroffer, D.; Hodgkin, S. T.; Hutton, A.; Jasniewicz, G.;
Jean-Antoine-Piccolo, A.; Jordan, S.; Korn, A. J.; Krone-Martins, A.;
Lanzafame, A. C.; Lebzelter, T.; Löffler, W.; Manteiga, M.; Marrese,
P. M.; Martín-Fleitas, J. M.; Moitinho, A.; Mora, A.; Muinonen, K.;
Osinde, J.; Pancino, E.; Pauwels, T.; Petit, J. -M.; Recio-Blanco, A.;
Richards, P. J.; Rimoldini, L.; Robin, A. C.; Sarro, L. M.; Siopis,
C.; Smith, M.; Sozzetti, A.; Süveges, M.; Torra, J.; van Reeven, W.;
Abbas, U.; Abreu Aramburu, A.; Accart, S.; Aerts, C.; Altavilla, G.;
Álvarez, M. A.; Alvarez, R.; Alves, J.; Anderson, R. I.; Andrei,
A. H.; Anglada Varela, E.; Antiche, E.; Antoja, T.; Arcay, B.;
Astraatmadja, T. L.; Bach, N.; Baker, S. G.; Balaguer-Núñez, L.;
Balm, P.; Barache, C.; Barata, C.; Barbato, D.; Barblan, F.; Barklem,
P. S.; Barrado, D.; Barros, M.; Barstow, M. A.; Bartholomé Muñoz,
S.; Bassilana, J. -L.; Becciani, U.; Bellazzini, M.; Berihuete, A.;
Bertone, S.; Bianchi, L.; Bienaymé, O.; Blanco-Cuaresma, S.; Boch,
T.; Boeche, C.; Bombrun, A.; Borrachero, R.; Bossini, D.; Bouquillon,
S.; Bourda, G.; Bragaglia, A.; Bramante, L.; Breddels, M. A.; Bressan,
A.; Brouillet, N.; Brüsemeister, T.; Brugaletta, E.; Bucciarelli,
B.; Burlacu, A.; Busonero, D.; Butkevich, A. G.; Buzzi, R.; Caffau,
E.; Cancelliere, R.; Cannizzaro, G.; Cantat-Gaudin, T.; Carballo,
R.; Carlucci, T.; Carrasco, J. M.; Casamiquela, L.; Castellani, M.;
Castro-Ginard, A.; Charlot, P.; Chemin, L.; Chiavassa, A.; Cocozza, G.;
Costigan, G.; Cowell, S.; Crifo, F.; Crosta, M.; Crowley, C.; Cuypers,
J.; Dafonte, C.; Damerdji, Y.; Dapergolas, A.; David, P.; David, M.;
de Laverny, P.; De Luise, F.; De March, R.; de Martino, D.; de Souza,
R.; de Torres, A.; Debosscher, J.; del Pozo, E.; Delbo, M.; Delgado,
A.; Delgado, H. E.; Di Matteo, P.; Diakite, S.; Diener, C.; Distefano,
E.; Dolding, C.; Drazinos, P.; Durán, J.; Edvardsson, B.; Enke, H.;
Eriksson, K.; Esquej, P.; Eynard Bontemps, G.; Fabre, C.; Fabrizio,
M.; Faigler, S.; Falcão, A. J.; Farràs Casas, M.; Federici, L.;
Fedorets, G.; Fernique, P.; Figueras, F.; Filippi, F.; Findeisen, K.;
Fonti, A.; Fraile, E.; Fraser, M.; Frézouls, B.; Gai, M.; Galleti, S.;
Garabato, D.; García-Sedano, F.; Garofalo, A.; Garralda, N.; Gavel,
A.; Gavras, P.; Gerssen, J.; Geyer, R.; Giacobbe, P.; Gilmore, G.;
Girona, S.; Giuffrida, G.; Glass, F.; Gomes, M.; Granvik, M.; Gueguen,
A.; Guerrier, A.; Guiraud, J.; Gutiérrez-Sánchez, R.; Haigron, R.;
Hatzidimitriou, D.; Hauser, M.; Haywood, M.; Heiter, U.; Helmi, A.;
Heu, J.; Hilger, T.; Hobbs, D.; Hofmann, W.; Holland, G.; Huckle,
H. E.; Hypki, A.; Icardi, V.; Janßen, K.; Jevardat de Fombelle, G.;
Jonker, P. G.; Juhász, Á. L.; Julbe, F.; Karampelas, A.; Kewley,
A.; Klar, J.; Kochoska, A.; Kohley, R.; Kolenberg, K.; Kontizas, M.;
Kontizas, E.; Koposov, S. E.; Kordopatis, G.; Kostrzewa-Rutkowska, Z.;
Koubsky, P.; Lambert, S.; Lanza, A. F.; Lasne, Y.; Lavigne, J. -B.;
Le Fustec, Y.; Le Poncin-Lafitte, C.; Lebreton, Y.; Leccia, S.;
Leclerc, N.; Lecoeur-Taibi, I.; Lenhardt, H.; Leroux, F.; Liao, S.;
Licata, E.; Lindstrøm, H. E. P.; Lister, T. A.; Livanou, E.; Lobel,
A.; López, M.; Managau, S.; Mann, R. G.; Mantelet, G.; Marchal, O.;
Marchant, J. M.; Marconi, M.; Marinoni, S.; Marschalkó, G.; Marshall,
D. J.; Martino, M.; Marton, G.; Mary, N.; Massari, D.; Matijevič,
G.; Mazeh, T.; McMillan, P. J.; Messina, S.; Michalik, D.; Millar,
N. R.; Molina, D.; Molinaro, R.; Molnár, L.; Montegriffo, P.; Mor,
R.; Morbidelli, R.; Morel, T.; Morris, D.; Mulone, A. F.; Muraveva,
T.; Musella, I.; Nelemans, G.; Nicastro, L.; Noval, L.; O'Mullane,
W.; Ordénovic, C.; Ordóñez-Blanco, D.; Osborne, P.; Pagani, C.;
Pagano, I.; Pailler, F.; Palacin, H.; Palaversa, L.; Panahi, A.;
Pawlak, M.; Piersimoni, A. M.; Pineau, F. -X.; Plachy, E.; Plum,
G.; Poggio, E.; Poujoulet, E.; Prša, A.; Pulone, L.; Racero, E.;
Ragaini, S.; Rambaux, N.; Ramos-Lerate, M.; Regibo, S.; Reylé, C.;
Riclet, F.; Ripepi, V.; Riva, A.; Rivard, A.; Rixon, G.; Roegiers,
T.; Roelens, M.; Romero-Gómez, M.; Rowell, N.; Royer, F.; Ruiz-Dern,
L.; Sadowski, G.; Sagristà Sellés, T.; Sahlmann, J.; Salgado, J.;
Salguero, E.; Sanna, N.; Santana-Ros, T.; Sarasso, M.; Savietto, H.;
Schultheis, M.; Sciacca, E.; Segol, M.; Segovia, J. C.; Ségransan, D.;
Shih, I. -C.; Siltala, L.; Silva, A. F.; Smart, R. L.; Smith, K. W.;
Solano, E.; Solitro, F.; Sordo, R.; Soria Nieto, S.; Souchay, J.;
Spagna, A.; Spoto, F.; Stampa, U.; Steele, I. A.; Steidelmüller, H.;
Stephenson, C. A.; Stoev, H.; Suess, F. F.; Surdej, J.; Szabados, L.;
Szegedi-Elek, E.; Tapiador, D.; Taris, F.; Tauran, G.; Taylor,
M. B.; Teixeira, R.; Terrett, D.; Teyssandier, P.; Thuillot, W.;
Titarenko, A.; Torra Clotet, F.; Turon, C.; Ulla, A.; Utrilla, E.;
Uzzi, S.; Vaillant, M.; Valentini, G.; Valette, V.; van Elteren,
A.; Van Hemelryck, E.; van Leeuwen, M.; Vaschetto, M.; Vecchiato,
A.; Veljanoski, J.; Viala, Y.; Vicente, D.; Vogt, S.; von Essen, C.;
Voss, H.; Votruba, V.; Voutsinas, S.; Walmsley, G.; Weiler, M.; Wertz,
O.; Wevers, T.; Wyrzykowski, Ł.; Yoldas, A.; Žerjal, M.; Ziaeepour,
H.; Zorec, J.; Zschocke, S.; Zucker, S.; Zurbach, C.; Zwitter, T.
Bibcode: 2018A&A...616A...1G
Altcode: 2018arXiv180409365G
Context. We present the second Gaia data release, Gaia DR2, consisting
of astrometry, photometry, radial velocities, and information on
astrophysical parameters and variability, for sources brighter than
magnitude 21. In addition epoch astrometry and photometry are provided
for a modest sample of minor planets in the solar system.
Aims: A summary of the contents of Gaia DR2 is presented, accompanied
by a discussion on the differences with respect to Gaia DR1 and
an overview of the main limitations which are still present in
the survey. Recommendations are made on the responsible use of
Gaia DR2 results.
Methods: The raw data collected with the
Gaia instruments during the first 22 months of the mission have
been processed by the Gaia Data Processing and Analysis Consortium
(DPAC) and turned into this second data release, which represents
a major advance with respect to Gaia DR1 in terms of completeness,
performance, and richness of the data products.
Results: Gaia
DR2 contains celestial positions and the apparent brightness in G for
approximately 1.7 billion sources. For 1.3 billion of those sources,
parallaxes and proper motions are in addition available. The sample
of sources for which variability information is provided is expanded
to 0.5 million stars. This data release contains four new elements:
broad-band colour information in the form of the apparent brightness
in the GBP (330-680 nm) and GRP (630-1050 nm)
bands is available for 1.4 billion sources; median radial velocities for
some 7 million sources are presented; for between 77 and 161 million
sources estimates are provided of the stellar effective temperature,
extinction, reddening, and radius and luminosity; and for a pre-selected
list of 14 000 minor planets in the solar system epoch astrometry
and photometry are presented. Finally, Gaia DR2 also represents a
new materialisation of the celestial reference frame in the optical,
the Gaia-CRF2, which is the first optical reference frame based solely
on extragalactic sources. There are notable changes in the photometric
system and the catalogue source list with respect to Gaia DR1, and we
stress the need to consider the two data releases as independent.
Conclusions: Gaia DR2 represents a major achievement for the Gaia
mission, delivering on the long standing promise to provide parallaxes
and proper motions for over 1 billion stars, and representing a first
step in the availability of complementary radial velocity and source
astrophysical information for a sample of stars in the Gaia survey
which covers a very substantial fraction of the volume of our galaxy.
Title: VizieR Online Data Catalog: 46 open clusters GaiaDR2 HR
diagrams (Gaia Collaboration, 2018)
Authors: Gaia Collaboration; Babusiaux, C.; van Leeuwen, F.;
Barstow; M., A.; Jordi, C.; Vallenari, A.; Bossini, A.; Bressan,
A.; Cantat-Gaudin, T.; van Leeuwen, M.; Brown, A. G. A.; Prusti,
T.; de Bruijne, J. H. J.; Bailer-Jones, C. A. L.; Biermann, M.;
Evans, D. W.; Eyer, L.; Jansen, F.; Klioner, S. A.; Lammers, U.;
Lindegren, L.; Luri, X.; Mignard, F.; Panem, C.; Pourbaix, D.;
Randich, S.; Sartoretti, P.; Siddiqui, H. I.; Soubiran, C.; Walton,
N. A.; Arenou, F.; Bastian, U.; Cropper, M.; Drimmel, R.; Katz, D.;
Lattanzi, M. G.; Bakker, J.; Cacciari, C.; Castaneda, J.; Chaoul,
L.; Cheek, N.; de Angeli, F.; Fabricius, C.; Guerra, R.; Holl, B.;
Masana, E.; Messineo, R.; Mowlavi, N.; Nienartowicz, K.; Panuzzo,
P.; Portell, J.; Riello, M.; Seabroke, G. M.; Tanga, P.; Thevenin,
F.; Gracia-Abril, G.; Comoretto, G.; Garcia-Reinaldos, M.; Teyssier,
D.; Altmann, M.; Andrae, R.; Audard, M.; Bellas-Velidis, I.; Benson,
K.; Berthier, J.; Blomme, R.; Burgess, P.; Busso, G.; Carry, B.;
Cellino, A.; Clementini, G.; Clotet, M.; Creevey, O.; Davidson,
M.; De Ridder, J.; Delchambre, L.; Dell'Oro, A.; Ducourant, C.;
Fernandez-Hernandez, J.; Fouesneau, M.; Fremat, Y.; Galluccio, L.;
Garcia-Torres, M.; Gonzalez-Nunez, J.; Gonzalez-Vidal, J. J.; Gosset,
E.; Guy, L. P.; Halbwachs, J. -L.; Hambly, N. C.; Harrison, D. L.;
Hernandez, J.; Hestroer, D.; Hodgkin, S. T.; Hutton, A.; Jasniewicz,
G.; Jean-Antoine-Piccolo, A.; Jordan, S.; Korn, A. J.; Krone-Martins,
A.; Lanzafame, A. C.; Lebzelter, T.; Loeer, W.; Manteiga, M.; Marrese,
P. M.; Martin-Fleitas, J. M.; Moitinho, A.; Mora, A.; Muinonen, K.;
Osinde, J.; Pancino, E.; Pauwels, T.; Petit, J. -M.; Recio-Blanco, A.;
Richards, P. J.; Rimoldini, L.; Robin, A. C.; Sarro, L. M.; Siopis,
C.; Smith, M.; Sozzetti, A.; Sueveges, M.; Torra, J.; van Reeven, W.;
Abbas, U.; Abreu Aramburu, A.; Accart, S.; Aerts, C.; Altavilla, G.;
Alvarez, M. A.; Alvarez, R.; Alves, J.; Anderson, R. I.; Andrei, A. H.;
Anglada Varela, E.; Antiche, E.; Antoja, T.; Arcay, B.; Astraatmadja,
T. L.; Bach, N.; Baker, S. G.; Balaguer-Nunez, L.; Balm, P.; Barache,
C.; Barata, C.; Barbato, D.; Barblan, F.; Barklem, P. S.; Barrado,
D.; Barros, M.; Bartholome Munoz, S.; Bassilana, J. -L.; Becciani, U.;
Bellazzini, M.; Berihuete, A.; Bertone, S.; Bianchi, L.; Bienayme, O.;
Blanco-Cuaresma, S.; Boch, T.; Boeche, C.; Bombrun, A.; Borrachero,
R.; Bouquillon, S.; Bourda, G.; Bragaglia, A.; Bramante, L.; Breddels,
M. A.; Brouillet, N.; Bruesemeister, T.; Brugaletta, E.; Bucciarelli,
B.; Burlacu, A.; Busonero, D.; Butkevich, A. G.; Buzzi, R.; Caau,
E.; Cancelliere, R.; Cannizzaro, G.; Carballo, R.; Carlucci, T.;
Carrasco, J. M.; Casamiquela, L.; Castellani, M.; Castro-Ginard,
A.; Charlot, P.; Chemin, L.; Chiavassa, A.; Cocozza, G.; Costigan,
G.; Cowell, S.; Crifo, F.; Crosta, M.; Crowley, C.; Cuypersy, J.;
Dafonte, C.; Damerdji, Y.; Dapergolas, A.; David, P.; David, M.; de
Laverny, P.; de Luise, F.; de March, R.; de Martino, D.; de Souza,
R.; de Torres, A.; Debosscher, J.; Del Pozo, E.; Delbo, M.; Delgado,
A.; Delgado, H. E.; Diakite, S.; Diener, C.; Distefano, E.; Dolding,
C.; Drazinos, P.; Duran, J.; Edvardsson, B.; Enke, H.; Eriksson, K.;
Esquej, P.; Eynard Bontemps, G.; Fabre, C.; Fabrizio, M.; Faigler,
S.; Falcao, A. J.; Farras Casas, M.; Federici, L.; Fedorets, G.;
Fernique, P.; Figueras, F.; Filippi, F.; Findeisen, K.; Fonti, A.;
Fraile, E.; Fraser, M.; Frezouls, B.; Gai, M.; Galleti, S.; Garabato,
D.; Garcia-Sedano, F.; Garofalo, A.; Garralda, N.; Gavel, A.; Gavras,
P.; Gerssen, J.; Geyer, R.; Giacobbe, P.; Gilmore, G.; Girona, S.;
Giurida, G.; Glass, F.; Gomes, M.; Granvik, M.; Gueguen, A.; Guerrier,
A.; Guiraud, J.; Gutierrez-Sanchez, R.; Haigron, R.; Hatzidimitriou,
D.; Hauser, M.; Haywood, M.; Heiter, U.; Helmi, A.; Heu, J.; Hilger,
T.; Hobbs, D.; Hofmann, W.; Holland, G.; Huckle, H. E.; Hypki, A.;
Icardi, V.; Janssen, K.; Jevardat de Fombelle, G.; Jonker, P. G.;
Juhasz, A. L.; Julbe, F.; Karampelas, A.; Kewley, A.; Klar, J.;
Kochoska, A.; Kohley, R.; Kolenberg, K.; Kontizas, M.; Kontizas, E.;
Koposov, S. E.; Kordopatis, G.; Kostrzewa-Rutkowska, Z.; Koubsky, P.;
Lambert, S.; Lanza, A. F.; Lasne, Y.; Lavigne, J. -B.; Le Fustec,
Y.; Le Poncin-Lafitte, C.; Lebreton, Y.; Leccia, S.; Leclerc, N.;
Lecoeur-Taibi, I.; Lenhardt, H.; Leroux, F.; Liao, S.; Licata, E.;
Lindstrom, H. E. P.; Lister, T. A.; Livanou, E.; Lobel, A.; Lopez, M.;
Managau, S.; Mann, R. G.; Mantelet, G.; Marchal, O.; Marchant, J. M.;
Marconi, M.; Marinoni, S.; Marschalko, G.; Marshall, D. J.; Martino,
M.; Marton, G.; Mary, N.; Massari, D.; Matijevi?C, G.; Mazeh, T.;
McMillan, P. J.; Messina, S.; Michalik, D.; Millar, N. R.; Molina,
D.; Molinaro, R.; Molnar, L.; Montegrio, P.; Mor, R.; Morbidelli,
R.; Morel, T.; Morris, D.; Mulone, A. F.; Muraveva, T.; Musella, I.;
Nelemans, G.; Nicastro, L.; Noval, L.; O'Mullane, W.; Ordenovic, C.;
Ordonez-Blanco, D.; Osborne, P.; Pagani, C.; Pagano, I.; Pailler, F.;
Palacin, H.; Palaversa, L.; Panahi, A.; Pawlak, M.; Piersimoni, A. M.;
Pineau, F. -X.; Plachy, E.; Plum, G.; Poggio, E.; Poujoulet, E.; Prsa,
A.; Pulone, L.; Racero, E.; Ragaini, S.; Rambaux, N.; Ramos-Lerate,
M.; Regibo, S.; Reyle, C.; Riclet, F.; Ripepi, V.; Riva, A.; Rivard,
A.; Rixon, G.; Roegiers, T.; Roelens, M.; Romero-Gomez, M.; Rowell,
N.; Royer, F.; Ruiz-Dern, L.; Sadowski, G.; Sagrista Selles, T.;
Sahlmann, J.; Salgado, J.; Salguero, E.; Sanna, N.; Santana-Ros,
T.; Sarasso, M.; Savietto, H.; Schultheis, M.; Sciacca, E.; Segol,
M.; Segovia, J. C.; Segransan, D.; Shih, I. -C.; Siltala, L.; Silva,
A. F.; Smart, R. L.; Smith, K. W.; Solano, E.; Solitro, F.; Sordo,
R.; Soria Nieto, S.; Souchay, J.; Spagna, A.; Spoto, F.; Stampa,
U.; Steele, I. A.; Steidelmueller, H.; Stephenson, C. A.; Stoev, H.;
Suess, F. F.; Surdej, J.; Szabados, L.; Szegedi-Elek, E.; Tapiador,
D.; Taris, F.; Tauran, G.; Taylor, M. B.; Teixeira, R.; Terrett, D.;
Teyssandier, P.; Thuillot, W.; Titarenko, A.; Torra Clotet, F.; Turon,
C.; Ulla, A.; Utrilla, E.; Uzzi, S.; Vaillant, M.; Valentini, G.;
Valette, V.; van Elteren, A.; van Hemelryck, E.; Vaschetto, M.;
Vecchiato, A.; Veljanoski, J.; Viala, Y.; Vicente, D.; Vogt, S.;
von Essen, C.; Voss, H.; Votruba, V.; Voutsinas, S.; Walmsley, G.;
Weiler, M.; Wertz, O.; Wevers, T.; Wyrzykowski, L.; Yoldas, A.; Zerjal,
M.; Ziaeepour, H.; Zorec, J.; Zschocke, S.; Zucker, S.; Zurbach, C.;
Zwitter, T.
Bibcode: 2018yCat..36160010G
Altcode:
We have determined the membership of 46 open clusters. For the nine
clusters within 250pc we determined optimised parallaxes based on
the combined information extracted from the measured parallax and
proper motion values. These clusters are : in Tables A1a & A3:
alphaPer, Blanco1, ComaBer, Hyades, IC2391, IC2602, NGC2451A, Pleiades,
Praesepe. The remaining 37 clusters are in Table A1b & A4: Coll140,
IC4651, IC4665, IC4725, IC4756, NGC0188, NGC0752, NGC0869, NGC0884,
NGC1039, NGC1901, NGC2158, NGC2168, NGC2232, NGC2323, NGC2360, NGC2422,
NGC2423, NGC2437, NGC2447, NGC2516, NGC2547, NGC2548, NGC2682, NGC3228,
NGC3532, NGC6025, NGC6281, NGC6405, NGC6475, NGC6633, NGC6774, NGC6793,
NGC7092, Stock2, Trump02, Trump10. (4 data files).
Title: White dwarfs in the Gaia era
Authors: Tremblay, P. -E.; Gentile-Fusillo, N.; Cummings, J.; Jordan,
S.; Gänsicke, B. T.; Kalirai, J. S.
Bibcode: 2018IAUS..330..317T
Altcode:
The vast majority of stars will become white dwarfs at the end of the
stellar life cycle. These remnants are precise cosmic clocks owing to
their well constrained cooling rates. Gaia Data Release 2 is expected
to discover hundreds of thousands of white dwarfs, which can then
be observed spectroscopically with WEAVE and 4MOST. By employing
spectroscopically derived atmospheric parameters combined with Gaia
parallaxes, white dwarfs can constrain the stellar formation history
in the early developing phases of the Milky Way, the initial mass
function in the 1.5 to 8 M ⊙ range, and the stellar
mass loss as well as the state of planetary systems during the post
main-sequence evolution.
Title: VizieR Online Data Catalog: Gaia DR2 sources in GC and dSph
(Gaia Collaboration+, 2018)
Authors: Gaia Collaboration; Helmi, A.; van Leeuwen, F.; Mc
Millan, P. J.; Massari, D.; Antoja, T.; Robin, A. C.; Lindegren,
L.; Bastian, U.; Arenou, F.; Babusiaux, C.; Biermann, M.; Breddels,
M. A.; Hobbs, D.; Jordi, C.; Pancino, E.; Reyle, C.; Veljanoski, J.;
Brown, A. G. A.; Vallenari, A.; Prusti, T.; de Bruijne, J. H. J.;
Bailer-Jones, C. A. L.; Evans, D. W.; Eyer, L.; Jansen, F.; Klioner,
S. A.; Lammers, U.; Luri, X.; Mignard, F.; Panem, C.; Pourbaix, D.;
Randich, S.; Sartoretti, P.; Siddiqui, H. I.; Soubiran, C.; Walton,
N. A.; Cropper, M.; Drimmel, R.; Katz, D.; Lattanzi, M. G.; Bakker,
J.; Cacciari, C.; Castaneda, J.; Chaoul, L.; Cheek, N.; de Angeli,
F.; Fabricius, C.; Guerra, R.; Holl, B.; Masana, E.; Messineo, R.;
Mowlavi, N.; Nienartowicz, K.; Panuzzo, P.; Portell, J.; Riello, M.;
Seabroke, G. M.; Tanga, P.; Thevenin, F.; Gracia-Abril, G.; Comoretto,
G.; Garcia-Reinaldos, M.; Teyssier, D.; Altmann, M.; Andrae, R.;
Audard, M.; Bellas-Velidis, I.; Benson, K.; Berthier, J.; Blomme,
R.; Burgess, P.; Busso, G.; Carry, B.; Cellino, A.; Clementini, G.;
Clotet, M.; ! Creevey, O.; Davidson, M.; De Ridder, J.; Delchambre,
L.; Dell'Oro, A.; Ducourant, C.; Fernandez-Hernandez, J.; Fouesneau,
M.; Fremat, Y.; Galluccio, L.; Garcia-Torres, M.; Gonzalez-Nunez,
J.; Gonzalez-Vidal, J. J.; Gosset, E.; Guy, L. P.; Halbwachs, J. -L.;
Hambly, N. C.; Harrison, D. L.; Hernandez, J.; Hestroffer, D.; Hodgkin,
S. T.; Hutton, A.; Jasniewicz, G.; Jean-Antoine-Piccolo, A.; Jordan,
S.; Korn, A. J.; Krone-Martins, A.; Lanzafame, A. C.; Lebzelter, T.;
Loeffler, W.; Manteiga, M.; Marrese, P. M.; Martin-Fleitas, J. M.;
Moitinho, A.; Mora, A.; Muinonen, K.; Osinde, J.; Pauwels, T.; Petit,
J. -M.; Recio-Blanco, A.; Richards, P. J.; Rimoldini, L.; Sarro,
L. M.; Siopis, C.; Smith, M.; Sozzetti, A.; Sueveges, M.; Torra, J.;
van Reeven, W.; Abbas, U.; Abreu Aramburu, A.; Accart, S.; Aerts,
C.; Altavilla, G.; Alvarez, M. A.; Alvarez, R.; Alves, J.; Anderson,
R. I.; Andrei, A. H.; Anglada Varela, E.; Antiche, E.; Arcay, B.;
Astraatmadja, T. L.; Bach, N.; Baker, S. G.; Balaguer-Nunez, L.;
Balm, P.; Barache, C.; Barata, C.; Barbato, D.; Barblan, F.; Barklem,
P. S.; Barra! Do, D.; Ba Rros, M.; Barstow, M. A.; Bartholome Munoz,
S.; Bassilana, J. -L.; Becciani, U.; Bellazzini, M.; Berihuete,
A.; Bertone, S.; Bianchi, L.; Bienayme, O.; Blanco-Cuaresma, S.;
Boch, T.; Boeche, C.; Bombrun, A.; Borrachero, R.; Bossini, D.;
Bouquillon, S.; Bourda, G.; Bragaglia, A.; Bramante, L.; Bressan,
A.; Brouillet, N.; Bruesemeister, T.; Brugaletta, E.; Bucciarelli,
B.; Burlacu, A.; Busonero, D.; Butkevich, A. G.; Buzzi, R.; Caffau,
E.; Cancelliere, R.; Cannizzaro, G.; Cantat-Gaudin, T.; Carballo,
R.; Carlucci, T.; Carrasco, J. M.; Casamiquela, L.; Castellani, M.;
Castro-Ginard, A.; Charlot, P.; Chemin, L.; Chiavassa, A.; Cocozza,
G.; Costigan, G.; Cowell, S.; Crifo, F.; Crosta, M.; Crowley, C.;
Cuypers, J.; Dafonte, C.; Damerdji, Y.; Dapergolas, A.; David, P.;
David, M.; de Laverny, P.; de Luise, F.; de March, R.; de Martino,
D.; de Souza, R.; de Torres, A.; Debosscher, J.; Del Pozo, E.; Delbo,
M.; Delgado, A.; Delgado, H. E.; Di Matteo, P.; Diakite, S.; Diener,
C.; Distefano, E.; Dolding, C.; Drazinos, P.; Duran, J.; Edvardsson,
B.; Enke, H.; Eriks! Son, K.; E Squej, P.; Eynard Bontemps, G.;
Fabre, C.; Fabrizio, M.; Faigler, S.; Falcao, A. J.; Farras Casas,
M.; Federici, L.; Fedorets, G.; Fernique, P.; Figueras, F.; Filippi,
F.; Findeisen, K.; Fonti, A.; Fraile, E.; Fraser, M.; Frezouls, B.;
Gai, M.; Galleti, S.; Garabato, D.; Garcia-Sedano, F.; Garofalo,
A.; Garralda, N.; Gavel, A.; Gavras, P.; Gerssen, J.; Geyer, R.;
Giacobbe, P.; Gilmore, G.; Girona, S.; Giuffrida, G.; Glass, F.;
Gomes, M.; Granvik, M.; Gueguen, A.; Guerrier, A.; Guiraud, J.;
Gutierrez-Sanchez, R.; Hofmann, W.; Holland, G.; Huckle, H. E.;
Hypki, A.; Icardi, V.; Janssen, K.; Jevardat de Fombelle, G.; Jonker,
P. G.; Juhasz, A. L.; Julbe, F.; Karampelas, A.; Kewley, A.; Klar,
J.; Kochoska, A.; Kohley, R.; Kolenberg, K.; Kontizas, M.; Kontizas,
E.; Koposov, S. E.; Kordopatis, G.; Kostrzewa-Rutkowska, Z.; Koubsky,
P.; Lambert, S.; Lanza, A. F.; Lasne, Y.; Lavigne, J. -B.; Le Fustec,
Y.; Le Poncin-Lafitte, C.; Lebreton, Y.; Leccia, S.; Leclerc, N.;
Lecoeur-Taibi, I.; Lenhardt, H.; Leroux, F.; Liao, S.; Licata, E.;
Lindstrom, H. E. P.; Lister, T. A.; ! Livanou, E.; Lobel, A.; Lopez,
M.; Managau, S.; Mann, R. G.; Mantelet, G.; Marchal, O.; Marchant,
J. M.; Marconi, M.; Marinoni, S.; Marschalko, G.; Marshall, D. J.;
Martino, M.; Marton, G.; Mary, N.; Matijevic, G.; Mazeh, T.; Messina,
S.; Michalik, D.; Millar, N. R.; Molina, D.; Molinaro, R.; Molnar,
L.; Montegriffo, P.; Mor, R.; Morbidelli, R.; Morel, T.; Morris, D.;
Mulone, A. F.; Muraveva, T.; Musella, I.; Nelemans, G.; Nicastro, L.;
Noval, L.; O'Mullane, W.; Ordenovic, C.; Ordonez-Blanco, D.; Osborne,
P.; Pagani, C.; Pagano, I.; Pailler, F.; Palacin, H.; Palaversa, L.;
Panahi, A.; Pawlak, M.; Piersimoni, A. M.; Pineau, F. -X.; Plachy, E.;
Plum, G.; Poggio, E.; Poujoulet, E.; Prsa, A.; Pulone, L.; Racero, E.;
Ragaini, S.; Rambaux, N.; Ramos-Lerate, M.; Regibo, S.; Riclet, F.;
Ripepi, V.; Riva, A.; Rivard, A.; Rixon, G.; Roegiers, T.; Roelens,
M.; Romero-Gomez, M.; Rowell, N.; Royer, F.; Ruiz-Dern, L.; Sadowski,
G.; Sagrista Selles, T.; Sahlmann, J.; Salgado, J.; Salguero, E.;
Sanna, N.; Santana-Ros, T.; Sarasso, M.; Savietto, H.; Schultheis,
M.; Sciacca, E.; Segol !, M.; Segov, Ia J. C.; Segransan, D.; Shih,
I. -C.; Siltala, L.; Silva, A. F.; Smart, R. L.; Smith, K. W.;
Solano, E.; Solitro, F.; Sordo, R.; Soria Nieto, S.; Souchay, J.;
Spagna, A.; Spoto, F.; Stampa, U.; Steele, I. A.; Steidelmueller, H.;
Stephenson, C. A.; Stoev, H.; Suess, F. F.; Surdej, J.; Szabados, L.;
Szegedi-Elek, E.; Tapiador, D.; Taris, F.; Tauran, G.; Taylor, M. B.;
Teixeira, R.; Terrett, D.; Teyssandier, P.; Thuillot, W.; Titarenko,
A.; Torra Clotet, F.; Turon, C.; Ulla, A.; Utrilla, E.; Uzzi,
S.; Vaillant, M.; Valentini, G.; Valette, V.; van Elteren, A.;
van Hemelryck, E.; van Leeuwen, M.; Vaschetto, M.; Vecchiato, A.;
Viala, Y.; Vicente, D.; Vogt, S.; von Essen, C.; Voss, H.; Votruba,
V.; Voutsinas, S.; Walmsley, G.; Weiler, M.; Wertz, O.; Wevems, T.;
Wyrzykowski, L.; Yoldas, A.; Zerjal, M.; Ziaeepour, H.; Zorec, J.;
Zschocke, S.; Zucker, S.; Zurbach, C.; Zwitter, T.
Bibcode: 2018yCat..36160012G
Altcode:
The files contains lists of possible members of each of the objects
(75 globular clusters, 9 dwarf spheroidal galaxies, the Bootes I UFD,
the LMC and SMC). The stars in these lists have been selected and used
to determine the astrometric parameters of the corresponding objects
following either the procedures described in Sec. 2.1 (for the clusters
and dwarfs) or in Sec. 2.2 (for the LMC and SMC). The first column is
the "source_id" as given by Gaia, the ra and declination of the star in
degrees, and its G-band magnitude (known as "photgmean_mag"
in the Gaia archive). (2 data files).
Title: Can magnetic fields suppress convection in the atmosphere of
cool white dwarfs? A case study on WD2105-820
Authors: Gentile Fusillo, N. P.; Tremblay, P. -E.; Jordan, S.;
Gänsicke, B. T.; Kalirai, J. S.; Cummings, J.
Bibcode: 2018MNRAS.473.3693G
Altcode: 2017arXiv171002151G; 2017arXiv171002151P
Around 10 per cent of white dwarfs exhibit global magnetic structures
with fields ranging from 1 kG to hundreds of MG. Recently, the first
radiation magnetohydrodynamics simulations of the atmosphere of white
dwarfs showed that convection should be suppressed in their photospheres
for magnetic fields with strengths B ≳ 50 kG. These predictions
are in agreement with our knowledge of stellar physics (e.g. energy
transfer in strong magnetic field regions of the solar photosphere),
but have yet to be directly confirmed from white dwarf observations. We
obtained Cosmic Origins Spectrograph (COS) far-ultraviolet (FUV)
spectroscopy of the weakly magnetic, hydrogen-atmosphere, white dwarf
WD2105-820 and of three additional non-magnetic, convective remnants
(all in the Teff range 9000-11 000 K). We fitted both the
COS and the already available optical spectra with convective and
radiative atmospheric models. As expected, we find that for two of the
non-magnetic comparison stars only convective model fits predicted
consistent Teff values from both the optical and the FUV
spectra. In contrast, for WD2105-820 only the best-fitting radiative
model produced consistent results.
Title: Gaia Data Release 1. The archive visualisation service
Authors: Moitinho, A.; Krone-Martins, A.; Savietto, H.; Barros,
M.; Barata, C.; Falcão, A. J.; Fernandes, T.; Alves, J.; Silva,
A. F.; Gomes, M.; Bakker, J.; Brown, A. G. A.; González-Núñez, J.;
Gracia-Abril, G.; Gutiérrez-Sánchez, R.; Hernández, J.; Jordan, S.;
Luri, X.; Merin, B.; Mignard, F.; Mora, A.; Navarro, V.; O'Mullane,
W.; Sagristà Sellés, T.; Salgado, J.; Segovia, J. C.; Utrilla,
E.; Arenou, F.; de Bruijne, J. H. J.; Jansen, F.; McCaughrean, M.;
O'Flaherty, K. S.; Taylor, M. B.; Vallenari, A.
Bibcode: 2017A&A...605A..52M
Altcode: 2017arXiv170800195M
Context. The first Gaia data release (DR1) delivered a catalogue
of astrometry and photometry for over a billion astronomical
sources. Within the panoplyof methods used for data exploration,
visualisation is often the starting point and even the guiding
reference for scientific thought. However, this is a volume of data
that cannot be efficiently explored using traditional tools, techniques,
and habits.
Aims: We aim to provide a global visual exploration
service for the Gaia archive, something that is not possible out of the
box for most people. The service has two main goals. The first is to
provide a software platform for interactive visual exploration of the
archive contents, using common personal computers and mobile devices
available to most users. The second aim is to produce intelligible and
appealing visual representations of the enormous information content
of the archive.
Methods: The interactive exploration service
follows a client-server design. The server runs close to the data,
at the archive, and is responsible for hiding as far as possible
the complexity and volume of the Gaia data from the client. This
is achieved by serving visual detail on demand. Levels of detail are
pre-computed using data aggregation and subsampling techniques. For DR1,
the client is a web application that provides an interactive multi-panel
visualisation workspace as well as a graphical user interface.
Results: The Gaia archive Visualisation Service offers a web-based
multi-panel interactive visualisation desktop in a browser tab. It
currently provides highly configurable 1D histograms and 2D scatter
plots of Gaia DR1 and the Tycho-Gaia Astrometric Solution (TGAS) with
linked views. An innovative feature is the creation of ADQL queries from
visually defined regions in plots. These visual queries are ready for
use in the Gaia Archive Search/data retrieval service. In addition,
regions around user-selected objects can be further examined with
automatically generated SIMBAD searches. Integration of the Aladin Lite
and JS9 applications add support to the visualisation of HiPS and FITS
maps. The production of the all-sky source density map that became the
iconic image of Gaia DR1 is described in detail.
Conclusions:
On the day of DR1, over seven thousand users accessed the Gaia Archive
visualisation portal. The system, running on a single machine, proved
robust and did not fail while enabling thousands of users to visualise
and explore the over one billion sources in DR1. There are still several
limitations, most noticeably that users may only choose from a list of
pre-computed visualisations. Thus, other visualisation applications that
can complement the archive service are examined. Finally, development
plans for Data Release 2 are presented.
Title: Gaia Data Release 1. Testing parallaxes with local Cepheids
and RR Lyrae stars
Authors: Gaia Collaboration; Clementini, G.; Eyer, L.; Ripepi, V.;
Marconi, M.; Muraveva, T.; Garofalo, A.; Sarro, L. M.; Palmer, M.;
Luri, X.; Molinaro, R.; Rimoldini, L.; Szabados, L.; Musella, I.;
Anderson, R. I.; Prusti, T.; de Bruijne, J. H. J.; Brown, A. G. A.;
Vallenari, A.; Babusiaux, C.; Bailer-Jones, C. A. L.; Bastian, U.;
Biermann, M.; Evans, D. W.; Jansen, F.; Jordi, C.; Klioner, S. A.;
Lammers, U.; Lindegren, L.; Mignard, F.; Panem, C.; Pourbaix,
D.; Randich, S.; Sartoretti, P.; Siddiqui, H. I.; Soubiran, C.;
Valette, V.; van Leeuwen, F.; Walton, N. A.; Aerts, C.; Arenou,
F.; Cropper, M.; Drimmel, R.; Høg, E.; Katz, D.; Lattanzi, M. G.;
O'Mullane, W.; Grebel, E. K.; Holland, A. D.; Huc, C.; Passot,
X.; Perryman, M.; Bramante, L.; Cacciari, C.; Castañeda, J.;
Chaoul, L.; Cheek, N.; De Angeli, F.; Fabricius, C.; Guerra, R.;
Hernández, J.; Jean-Antoine-Piccolo, A.; Masana, E.; Messineo,
R.; Mowlavi, N.; Nienartowicz, K.; Ordóñez-Blanco, D.; Panuzzo,
P.; Portell, J.; Richards, P. J.; Riello, M.; Seabroke, G. M.;
Tanga, P.; Thévenin, F.; Torra, J.; Els, S. G.; Gracia-Abril, G.;
Comoretto, G.; Garcia-Reinaldos, M.; Lock, T.; Mercier, E.; Altmann,
M.; Andrae, R.; Astraatmadja, T. L.; Bellas-Velidis, I.; Benson,
K.; Berthier, J.; Blomme, R.; Busso, G.; Carry, B.; Cellino, A.;
Cowell, S.; Creevey, O.; Cuypers, J.; Davidson, M.; De Ridder, J.;
de Torres, A.; Delchambre, L.; Dell'Oro, A.; Ducourant, C.; Frémat,
Y.; García-Torres, M.; Gosset, E.; Halbwachs, J. -L.; Hambly, N. C.;
Harrison, D. L.; Hauser, M.; Hestroffer, D.; Hodgkin, S. T.; Huckle,
H. E.; Hutton, A.; Jasniewicz, G.; Jordan, S.; Kontizas, M.; Korn,
A. J.; Lanzafame, A. C.; Manteiga, M.; Moitinho, A.; Muinonen, K.;
Osinde, J.; Pancino, E.; Pauwels, T.; Petit, J. -M.; Recio-Blanco,
A.; Robin, A. C.; Siopis, C.; Smith, M.; Smith, K. W.; Sozzetti, A.;
Thuillot, W.; van Reeven, W.; Viala, Y.; Abbas, U.; Abreu Aramburu,
A.; Accart, S.; Aguado, J. J.; Allan, P. M.; Allasia, W.; Altavilla,
G.; Álvarez, M. A.; Alves, J.; Andrei, A. H.; Anglada Varela, E.;
Antiche, E.; Antoja, T.; Antón, S.; Arcay, B.; Bach, N.; Baker,
S. G.; Balaguer-Núñez, L.; Barache, C.; Barata, C.; Barbier, A.;
Barblan, F.; Barrado y Navascués, D.; Barros, M.; Barstow, M. A.;
Becciani, U.; Bellazzini, M.; Bello García, A.; Belokurov, V.;
Bendjoya, P.; Berihuete, A.; Bianchi, L.; Bienaymé, O.; Billebaud,
F.; Blagorodnova, N.; Blanco-Cuaresma, S.; Boch, T.; Bombrun, A.;
Borrachero, R.; Bouquillon, S.; Bourda, G.; Bragaglia, A.; Breddels,
M. A.; Brouillet, N.; Brüsemeister, T.; Bucciarelli, B.; Burgess,
P.; Burgon, R.; Burlacu, A.; Busonero, D.; Buzzi, R.; Caffau,
E.; Cambras, J.; Campbell, H.; Cancelliere, R.; Cantat-Gaudin, T.;
Carlucci, T.; Carrasco, J. M.; Castellani, M.; Charlot, P.; Charnas,
J.; Chiavassa, A.; Clotet, M.; Cocozza, G.; Collins, R. S.; Costigan,
G.; Crifo, F.; Cross, N. J. G.; Crosta, M.; Crowley, C.; Dafonte,
C.; Damerdji, Y.; Dapergolas, A.; David, P.; David, M.; De Cat, P.;
de Felice, F.; de Laverny, P.; De Luise, F.; De March, R.; de Souza,
R.; Debosscher, J.; del Pozo, E.; Delbo, M.; Delgado, A.; Delgado,
H. E.; Di Matteo, P.; Diakite, S.; Distefano, E.; Dolding, C.; Dos
Anjos, S.; Drazinos, P.; Durán, J.; Dzigan, Y.; Edvardsson, B.;
Enke, H.; Evans, N. W.; Eynard Bontemps, G.; Fabre, C.; Fabrizio,
M.; Falcão, A. J.; Farràs Casas, M.; Federici, L.; Fedorets,
G.; Fernández-Hernández, J.; Fernique, P.; Fienga, A.; Figueras,
F.; Filippi, F.; Findeisen, K.; Fonti, A.; Fouesneau, M.; Fraile,
E.; Fraser, M.; Fuchs, J.; Gai, M.; Galleti, S.; Galluccio, L.;
Garabato, D.; García-Sedano, F.; Garralda, N.; Gavras, P.; Gerssen,
J.; Geyer, R.; Gilmore, G.; Girona, S.; Giuffrida, G.; Gomes, M.;
González-Marcos, A.; González-Núñez, J.; González-Vidal, J. J.;
Granvik, M.; Guerrier, A.; Guillout, P.; Guiraud, J.; Gúrpide, A.;
Gutiérrez-Sánchez, R.; Guy, L. P.; Haigron, R.; Hatzidimitriou, D.;
Haywood, M.; Heiter, U.; Helmi, A.; Hobbs, D.; Hofmann, W.; Holl, B.;
Holland, G.; Hunt, J. A. S.; Hypki, A.; Icardi, V.; Irwin, M.; Jevardat
de Fombelle, G.; Jofré, P.; Jonker, P. G.; Jorissen, A.; Julbe, F.;
Karampelas, A.; Kochoska, A.; Kohley, R.; Kolenberg, K.; Kontizas,
E.; Koposov, S. E.; Kordopatis, G.; Koubsky, P.; Krone-Martins, A.;
Kudryashova, M.; Bachchan, R. K.; Lacoste-Seris, F.; Lanza, A. F.;
Lavigne, J. -B.; Le Poncin-Lafitte, C.; Lebreton, Y.; Lebzelter, T.;
Leccia, S.; Leclerc, N.; Lecoeur-Taibi, I.; Lemaitre, V.; Lenhardt,
H.; Leroux, F.; Liao, S.; Licata, E.; Lindstrøm, H. E. P.; Lister,
T. A.; Livanou, E.; Lobel, A.; Löffler, W.; López, M.; Lorenz, D.;
MacDonald, I.; Magalhães Fernandes, T.; Managau, S.; Mann, R. G.;
Mantelet, G.; Marchal, O.; Marchant, J. M.; Marinoni, S.; Marrese,
P. M.; Marschalkó, G.; Marshall, D. J.; Martín-Fleitas, J. M.;
Martino, M.; Mary, N.; Matijevič, G.; McMillan, P. J.; Messina,
S.; Michalik, D.; Millar, N. R.; Miranda, B. M. H.; Molina, D.;
Molinaro, M.; Molnár, L.; Moniez, M.; Montegriffo, P.; Mor, R.;
Mora, A.; Morbidelli, R.; Morel, T.; Morgenthaler, S.; Morris, D.;
Mulone, A. F.; Narbonne, J.; Nelemans, G.; Nicastro, L.; Noval, L.;
Ordénovic, C.; Ordieres-Meré, J.; Osborne, P.; Pagani, C.; Pagano,
I.; Pailler, F.; Palacin, H.; Palaversa, L.; Parsons, P.; Pecoraro,
M.; Pedrosa, R.; Pentikäinen, H.; Pichon, B.; Piersimoni, A. M.;
Pineau, F. -X.; Plachy, E.; Plum, G.; Poujoulet, E.; Prša, A.;
Pulone, L.; Ragaini, S.; Rago, S.; Rambaux, N.; Ramos-Lerate, M.;
Ranalli, P.; Rauw, G.; Read, A.; Regibo, S.; Reylé, C.; Ribeiro,
R. A.; Riva, A.; Rixon, G.; Roelens, M.; Romero-Gómez, M.; Rowell,
N.; Royer, F.; Ruiz-Dern, L.; Sadowski, G.; Sagristà Sellés, T.;
Sahlmann, J.; Salgado, J.; Salguero, E.; Sarasso, M.; Savietto, H.;
Schultheis, M.; Sciacca, E.; Segol, M.; Segovia, J. C.; Segransan,
D.; Shih, I. -C.; Smareglia, R.; Smart, R. L.; Solano, E.; Solitro,
F.; Sordo, R.; Soria Nieto, S.; Souchay, J.; Spagna, A.; Spoto, F.;
Stampa, U.; Steele, I. A.; Steidelmüller, H.; Stephenson, C. A.;
Stoev, H.; Suess, F. F.; Süveges, M.; Surdej, J.; Szegedi-Elek, E.;
Tapiador, D.; Taris, F.; Tauran, G.; Taylor, M. B.; Teixeira, R.;
Terrett, D.; Tingley, B.; Trager, S. C.; Turon, C.; Ulla, A.; Utrilla,
E.; Valentini, G.; van Elteren, A.; Van Hemelryck, E.; van Leeuwen, M.;
Varadi, M.; Vecchiato, A.; Veljanoski, J.; Via, T.; Vicente, D.; Vogt,
S.; Voss, H.; Votruba, V.; Voutsinas, S.; Walmsley, G.; Weiler, M.;
Weingrill, K.; Wevers, T.; Wyrzykowski, Ł.; Yoldas, A.; Žerjal, M.;
Zucker, S.; Zurbach, C.; Zwitter, T.; Alecu, A.; Allen, M.; Allende
Prieto, C.; Amorim, A.; Anglada-Escudé, G.; Arsenijevic, V.; Azaz,
S.; Balm, P.; Beck, M.; Bernstein, H. -H.; Bigot, L.; Bijaoui, A.;
Blasco, C.; Bonfigli, M.; Bono, G.; Boudreault, S.; Bressan, A.;
Brown, S.; Brunet, P. -M.; Bunclark, P.; Buonanno, R.; Butkevich,
A. G.; Carret, C.; Carrion, C.; Chemin, L.; Chéreau, F.; Corcione,
L.; Darmigny, E.; de Boer, K. S.; de Teodoro, P.; de Zeeuw, P. T.;
Delle Luche, C.; Domingues, C. D.; Dubath, P.; Fodor, F.; Frézouls,
B.; Fries, A.; Fustes, D.; Fyfe, D.; Gallardo, E.; Gallegos, J.;
Gardiol, D.; Gebran, M.; Gomboc, A.; Gómez, A.; Grux, E.; Gueguen,
A.; Heyrovsky, A.; Hoar, J.; Iannicola, G.; Isasi Parache, Y.;
Janotto, A. -M.; Joliet, E.; Jonckheere, A.; Keil, R.; Kim, D. -W.;
Klagyivik, P.; Klar, J.; Knude, J.; Kochukhov, O.; Kolka, I.; Kos,
J.; Kutka, A.; Lainey, V.; LeBouquin, D.; Liu, C.; Loreggia, D.;
Makarov, V. V.; Marseille, M. G.; Martayan, C.; Martinez-Rubi, O.;
Massart, B.; Meynadier, F.; Mignot, S.; Munari, U.; Nguyen, A. -T.;
Nordlander, T.; O'Flaherty, K. S.; Ocvirk, P.; Olias Sanz, A.; Ortiz,
P.; Osorio, J.; Oszkiewicz, D.; Ouzounis, A.; Park, P.; Pasquato, E.;
Peltzer, C.; Peralta, J.; Péturaud, F.; Pieniluoma, T.; Pigozzi, E.;
Poels, J.; Prat, G.; Prod'homme, T.; Raison, F.; Rebordao, J. M.;
Risquez, D.; Rocca-Volmerange, B.; Rosen, S.; Ruiz-Fuertes, M. I.;
Russo, F.; Serraller Vizcaino, I.; Short, A.; Siebert, A.; Silva, H.;
Sinachopoulos, D.; Slezak, E.; Soffel, M.; Sosnowska, D.; Straižys,
V.; ter Linden, M.; Terrell, D.; Theil, S.; Tiede, C.; Troisi, L.;
Tsalmantza, P.; Tur, D.; Vaccari, M.; Vachier, F.; Valles, P.; Van
Hamme, W.; Veltz, L.; Virtanen, J.; Wallut, J. -M.; Wichmann, R.;
Wilkinson, M. I.; Ziaeepour, H.; Zschocke, S.
Bibcode: 2017A&A...605A..79G
Altcode: 2017arXiv170500688G; 2017A&A...605A..79.
Context. Parallaxes for 331 classical Cepheids, 31 Type II Cepheids,
and 364 RR Lyrae stars in common between Gaia and the HIPPARCOS and
Tycho-2 catalogues are published in Gaia Data Release 1 (DR1) as part
of the Tycho-Gaia Astrometric Solution (TGAS).
Aims: In order to
test these first parallax measurements of the primary standard candles
of the cosmological distance ladder, which involve astrometry collected
by Gaia during the initial 14 months of science operation, we compared
them with literature estimates and derived new period-luminosity (PL),
period-Wesenheit (PW) relations for classical and Type II Cepheids and
infrared PL, PL-metallicity (PLZ), and optical luminosity-metallicity
(MV-[Fe/H]) relations for the RR Lyrae stars, with zero
points based on TGAS.
Methods: Classical Cepheids were carefully
selected in order to discard known or suspected binary systems. The
final sample comprises 102 fundamental mode pulsators with periods
ranging from 1.68 to 51.66 days (of which 33 with σϖ/ϖ<
0.5). The Type II Cepheids include a total of 26 W Virginis and BL
Herculis stars spanning the period range from 1.16 to 30.00 days
(of which only 7 with σϖ/ϖ< 0.5). The RR Lyrae stars
include 200 sources with pulsation period ranging from 0.27 to 0.80
days (of which 112 with σϖ/ϖ< 0.5). The new relations
were computed using multi-band (V,I,J,Ks) photometry
and spectroscopic metal abundances available in the literature, and
by applying three alternative approaches: (i) linear least-squares
fitting of the absolute magnitudes inferred from direct transformation
of the TGAS parallaxes; (ii) adopting astrometry-based luminosities;
and (iii) using a Bayesian fitting approach. The last two methods work
in parallax space where parallaxes are used directly, thus maintaining
symmetrical errors and allowing negative parallaxes to be used. The
TGAS-based PL,PW,PLZ, and MV- [Fe/H] relations are discussed
by comparing the distance to the Large Magellanic Cloud provided by
different types of pulsating stars and alternative fitting methods.
Results: Good agreement is found from direct comparison of the
parallaxes of RR Lyrae stars for which both TGAS and HST measurements
are available. Similarly, very good agreement is found between the
TGAS values and the parallaxes inferred from the absolute magnitudes
of Cepheids and RR Lyrae stars analysed with the Baade-Wesselink
method. TGAS values also compare favourably with the parallaxes inferred
by theoretical model fitting of the multi-band light curves for two
of the three classical Cepheids and one RR Lyrae star, which were
analysed with this technique in our samples. The K-band PL relations
show the significant improvement of the TGAS parallaxes for Cepheids
and RR Lyrae stars with respect to the HIPPARCOS measurements. This
is particularly true for the RR Lyrae stars for which improvement
in quality and statistics is impressive.
Conclusions: TGAS
parallaxes bring a significant added value to the previous HIPPARCOS
estimates. The relations presented in this paper represent the first
Gaia-calibrated relations and form a work-in-progress milestone report
in the wait for Gaia-only parallaxes of which a first solution will
become available with Gaia Data Release 2 (DR2) in 2018. Full
Tables A.1-A.3 are only available at the CDS via anonymous ftp to
http://cdsarc.u-strasbg.fr
(http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/605/A79
Title: VizieR Online Data Catalog: SDSS magnetic white dwarf stars
(Kepler+, 2013)
Authors: Kepler, S. O.; Pelisoli, I.; Jordan, S.; Kleinman, S. J.;
Koester, D.; Kulebi, B.; Pecanha, V.; Castanheira, B. G.; Nitta, A.;
Costa, J. E. S.; Winget, D. E.; Kanaan, A.; Fraga, L.
Bibcode: 2017yCat..74292934K
Altcode:
We classified more than 48000 spectra, selected as possible white dwarf
stars from the SDSS DR7 by their colours, through visual inspection and
detected Zeeman splittings in 521 DA stars. Table 1 shows the estimated
values for the magnetic fields for the 521 spectra we measured. (1 data file).
Title: Gaia Data Release 1. Open cluster astrometry: performance,
limitations, and future prospects
Authors: Gaia Collaboration; van Leeuwen, F.; Vallenari, A.; Jordi,
C.; Lindegren, L.; Bastian, U.; Prusti, T.; de Bruijne, J. H. J.;
Brown, A. G. A.; Babusiaux, C.; Bailer-Jones, C. A. L.; Biermann,
M.; Evans, D. W.; Eyer, L.; Jansen, F.; Klioner, S. A.; Lammers,
U.; Luri, X.; Mignard, F.; Panem, C.; Pourbaix, D.; Randich, S.;
Sartoretti, P.; Siddiqui, H. I.; Soubiran, C.; Valette, V.; Walton,
N. A.; Aerts, C.; Arenou, F.; Cropper, M.; Drimmel, R.; Høg, E.; Katz,
D.; Lattanzi, M. G.; O'Mullane, W.; Grebel, E. K.; Holland, A. D.; Huc,
C.; Passot, X.; Perryman, M.; Bramante, L.; Cacciari, C.; Castañeda,
J.; Chaoul, L.; Cheek, N.; De Angeli, F.; Fabricius, C.; Guerra, R.;
Hernández, J.; Jean-Antoine-Piccolo, A.; Masana, E.; Messineo, R.;
Mowlavi, N.; Nienartowicz, K.; Ordóñez-Blanco, D.; Panuzzo, P.;
Portell, J.; Richards, P. J.; Riello, M.; Seabroke, G. M.; Tanga, P.;
Thévenin, F.; Torra, J.; Els, S. G.; Gracia-Abril, G.; Comoretto,
G.; Garcia-Reinaldos, M.; Lock, T.; Mercier, E.; Altmann, M.; Andrae,
R.; Astraatmadja, T. L.; Bellas-Velidis, I.; Benson, K.; Berthier,
J.; Blomme, R.; Busso, G.; Carry, B.; Cellino, A.; Clementini, G.;
Cowell, S.; Creevey, O.; Cuypers, J.; Davidson, M.; De Ridder, J.;
de Torres, A.; Delchambre, L.; Dell'Oro, A.; Ducourant, C.; Frémat,
Y.; García-Torres, M.; Gosset, E.; Halbwachs, J. -L.; Hambly, N. C.;
Harrison, D. L.; Hauser, M.; Hestroffer, D.; Hodgkin, S. T.; Huckle,
H. E.; Hutton, A.; Jasniewicz, G.; Jordan, S.; Kontizas, M.; Korn,
A. J.; Lanzafame, A. C.; Manteiga, M.; Moitinho, A.; Muinonen, K.;
Osinde, J.; Pancino, E.; Pauwels, T.; Petit, J. -M.; Recio-Blanco,
A.; Robin, A. C.; Sarro, L. M.; Siopis, C.; Smith, M.; Smith, K. W.;
Sozzetti, A.; Thuillot, W.; van Reeven, W.; Viala, Y.; Abbas, U.;
Abreu Aramburu, A.; Accart, S.; Aguado, J. J.; Allan, P. M.; Allasia,
W.; Altavilla, G.; Álvarez, M. A.; Alves, J.; Anderson, R. I.; Andrei,
A. H.; Anglada Varela, E.; Antiche, E.; Antoja, T.; Antón, S.; Arcay,
B.; Bach, N.; Baker, S. G.; Balaguer-Núñez, L.; Barache, C.; Barata,
C.; Barbier, A.; Barblan, F.; Barrado y Navascués, D.; Barros, M.;
Barstow, M. A.; Becciani, U.; Bellazzini, M.; Bello García, A.;
Belokurov, V.; Bendjoya, P.; Berihuete, A.; Bianchi, L.; Bienaymé,
O.; Billebaud, F.; Blagorodnova, N.; Blanco-Cuaresma, S.; Boch, T.;
Bombrun, A.; Borrachero, R.; Bouquillon, S.; Bourda, G.; Bouy, H.;
Bragaglia, A.; Breddels, M. A.; Brouillet, N.; Brüsemeister, T.;
Bucciarelli, B.; Burgess, P.; Burgon, R.; Burlacu, A.; Busonero, D.;
Buzzi, R.; Caffau, E.; Cambras, J.; Campbell, H.; Cancelliere, R.;
Cantat-Gaudin, T.; Carlucci, T.; Carrasco, J. M.; Castellani, M.;
Charlot, P.; Charnas, J.; Chiavassa, A.; Clotet, M.; Cocozza, G.;
Collins, R. S.; Costigan, G.; Crifo, F.; Cross, N. J. G.; Crosta, M.;
Crowley, C.; Dafonte, C.; Damerdji, Y.; Dapergolas, A.; David, P.;
David, M.; De Cat, P.; de Felice, F.; de Laverny, P.; De Luise, F.;
De March, R.; de Martino, D.; de Souza, R.; Debosscher, J.; del Pozo,
E.; Delbo, M.; Delgado, A.; Delgado, H. E.; Di Matteo, P.; Diakite, S.;
Distefano, E.; Dolding, C.; Dos Anjos, S.; Drazinos, P.; Durán, J.;
Dzigan, Y.; Edvardsson, B.; Enke, H.; Evans, N. W.; Eynard Bontemps,
G.; Fabre, C.; Fabrizio, M.; Faigler, S.; Falcão, A. J.; Farràs
Casas, M.; Federici, L.; Fedorets, G.; Fernández-Hernández, J.;
Fernique, P.; Fienga, A.; Figueras, F.; Filippi, F.; Findeisen, K.;
Fonti, A.; Fouesneau, M.; Fraile, E.; Fraser, M.; Fuchs, J.; Gai, M.;
Galleti, S.; Galluccio, L.; Garabato, D.; García-Sedano, F.; Garofalo,
A.; Garralda, N.; Gavras, P.; Gerssen, J.; Geyer, R.; Gilmore,
G.; Girona, S.; Giuffrida, G.; Gomes, M.; González-Marcos, A.;
González-Núñez, J.; González-Vidal, J. J.; Granvik, M.; Guerrier,
A.; Guillout, P.; Guiraud, J.; Gúrpide, A.; Gutiérrez-Sánchez,
R.; Guy, L. P.; Haigron, R.; Hatzidimitriou, D.; Haywood, M.; Heiter,
U.; Helmi, A.; Hobbs, D.; Hofmann, W.; Holl, B.; Holland, G.; Hunt,
J. A. S.; Hypki, A.; Icardi, V.; Irwin, M.; Jevardat de Fombelle,
G.; Jofré, P.; Jonker, P. G.; Jorissen, A.; Julbe, F.; Karampelas,
A.; Kochoska, A.; Kohley, R.; Kolenberg, K.; Kontizas, E.; Koposov,
S. E.; Kordopatis, G.; Koubsky, P.; Krone-Martins, A.; Kudryashova, M.;
Kull, I.; Bachchan, R. K.; Lacoste-Seris, F.; Lanza, A. F.; Lavigne,
J. -B.; Le Poncin-Lafitte, C.; Lebreton, Y.; Lebzelter, T.; Leccia, S.;
Leclerc, N.; Lecoeur-Taibi, I.; Lemaitre, V.; Lenhardt, H.; Leroux, F.;
Liao, S.; Licata, E.; Lindstrøm, H. E. P.; Lister, T. A.; Livanou,
E.; Lobel, A.; Löffler, W.; López, M.; Lorenz, D.; MacDonald, I.;
Magalhães Fernandes, T.; Managau, S.; Mann, R. G.; Mantelet, G.;
Marchal, O.; Marchant, J. M.; Marconi, M.; Marinoni, S.; Marrese,
P. M.; Marschalkó, G.; Marshall, D. J.; Martín-Fleitas, J. M.;
Martino, M.; Mary, N.; Matijevič, G.; Mazeh, T.; McMillan, P. J.;
Messina, S.; Michalik, D.; Millar, N. R.; Miranda, B. M. H.; Molina,
D.; Molinaro, R.; Molinaro, M.; Molnár, L.; Moniez, M.; Montegriffo,
P.; Mor, R.; Mora, A.; Morbidelli, R.; Morel, T.; Morgenthaler, S.;
Morris, D.; Mulone, A. F.; Muraveva, T.; Musella, I.; Narbonne, J.;
Nelemans, G.; Nicastro, L.; Noval, L.; Ordénovic, C.; Ordieres-Meré,
J.; Osborne, P.; Pagani, C.; Pagano, I.; Pailler, F.; Palacin, H.;
Palaversa, L.; Parsons, P.; Pecoraro, M.; Pedrosa, R.; Pentikäinen,
H.; Pichon, B.; Piersimoni, A. M.; Pineau, F. -X.; Plachy, E.;
Plum, G.; Poujoulet, E.; Prša, A.; Pulone, L.; Ragaini, S.; Rago,
S.; Rambaux, N.; Ramos-Lerate, M.; Ranalli, P.; Rauw, G.; Read, A.;
Regibo, S.; Reylé, C.; Ribeiro, R. A.; Rimoldini, L.; Ripepi, V.;
Riva, A.; Rixon, G.; Roelens, M.; Romero-Gómez, M.; Rowell, N.; Royer,
F.; Ruiz-Dern, L.; Sadowski, G.; Sagristà Sellés, T.; Sahlmann, J.;
Salgado, J.; Salguero, E.; Sarasso, M.; Savietto, H.; Schultheis, M.;
Sciacca, E.; Segol, M.; Segovia, J. C.; Segransan, D.; Shih, I. -C.;
Smareglia, R.; Smart, R. L.; Solano, E.; Solitro, F.; Sordo, R.;
Soria Nieto, S.; Souchay, J.; Spagna, A.; Spoto, F.; Stampa, U.;
Steele, I. A.; Steidelmüller, H.; Stephenson, C. A.; Stoev, H.;
Suess, F. F.; Süveges, M.; Surdej, J.; Szabados, L.; Szegedi-Elek,
E.; Tapiador, D.; Taris, F.; Tauran, G.; Taylor, M. B.; Teixeira, R.;
Terrett, D.; Tingley, B.; Trager, S. C.; Turon, C.; Ulla, A.; Utrilla,
E.; Valentini, G.; van Elteren, A.; Van Hemelryck, E.; vanLeeuwen,
M.; Varadi, M.; Vecchiato, A.; Veljanoski, J.; Via, T.; Vicente, D.;
Vogt, S.; Voss, H.; Votruba, V.; Voutsinas, S.; Walmsley, G.; Weiler,
M.; Weingrill, K.; Wevers, T.; Wyrzykowski, Ł.; Yoldas, A.; Žerjal,
M.; Zucker, S.; Zurbach, C.; Zwitter, T.; Alecu, A.; Allen, M.; Allende
Prieto, C.; Amorim, A.; Anglada-Escudé, G.; Arsenijevic, V.; Azaz, S.;
Balm, P.; Beck, M.; Bernstein, H. -H.; Bigot, L.; Bijaoui, A.; Blasco,
C.; Bonfigli, M.; Bono, G.; Boudreault, S.; Bressan, A.; Brown, S.;
Brunet, P. -M.; Bunclark, P.; Buonanno, R.; Butkevich, A. G.; Carret,
C.; Carrion, C.; Chemin, L.; Chéreau, F.; Corcione, L.; Darmigny,
E.; de Boer, K. S.; de Teodoro, P.; de Zeeuw, P. T.; Delle Luche,
C.; Domingues, C. D.; Dubath, P.; Fodor, F.; Frézouls, B.; Fries,
A.; Fustes, D.; Fyfe, D.; Gallardo, E.; Gallegos, J.; Gardiol, D.;
Gebran, M.; Gomboc, A.; Gómez, A.; Grux, E.; Gueguen, A.; Heyrovsky,
A.; Hoar, J.; Iannicola, G.; Isasi Parache, Y.; Janotto, A. -M.;
Joliet, E.; Jonckheere, A.; Keil, R.; Kim, D. -W.; Klagyivik, P.;
Klar, J.; Knude, J.; Kochukhov, O.; Kolka, I.; Kos, J.; Kutka, A.;
Lainey, V.; LeBouquin, D.; Liu, C.; Loreggia, D.; Makarov, V. V.;
Marseille, M. G.; Martayan, C.; Martinez-Rubi, O.; Massart, B.;
Meynadier, F.; Mignot, S.; Munari, U.; Nguyen, A. -T.; Nordlander,
T.; O'Flaherty, K. S.; Ocvirk, P.; Olias Sanz, A.; Ortiz, P.; Osorio,
J.; Oszkiewicz, D.; Ouzounis, A.; Palmer, M.; Park, P.; Pasquato, E.;
Peltzer, C.; Peralta, J.; Péturaud, F.; Pieniluoma, T.; Pigozzi, E.;
Poels, J.; Prat, G.; Prod'homme, T.; Raison, F.; Rebordao, J. M.;
Risquez, D.; Rocca-Volmerange, B.; Rosen, S.; Ruiz-Fuertes, M. I.;
Russo, F.; Sembay, S.; Serraller Vizcaino, I.; Short, A.; Siebert,
A.; Silva, H.; Sinachopoulos, D.; Slezak, E.; Soffel, M.; Sosnowska,
D.; Straižys, V.; ter Linden, M.; Terrell, D.; Theil, S.; Tiede,
C.; Troisi, L.; Tsalmantza, P.; Tur, D.; Vaccari, M.; Vachier, F.;
Valles, P.; Van Hamme, W.; Veltz, L.; Virtanen, J.; Wallut, J. -M.;
Wichmann, R.; Wilkinson, M. I.; Ziaeepour, H.; Zschocke, S.
Bibcode: 2017A&A...601A..19G
Altcode: 2017arXiv170301131G
Context. The first Gaia Data Release contains the Tycho-Gaia Astrometric
Solution (TGAS). This is a subset of about 2 million stars for which,
besides the position and photometry, the proper motion and parallax are
calculated using HIPPARCOS and Tycho-2 positions in 1991.25 as prior
information.
Aims: We investigate the scientific potential
and limitations of the TGAS component by means of the astrometric
data for open clusters.
Methods: Mean cluster parallax and
proper motion values are derived taking into account the error
correlations within the astrometric solutions for individual stars,
an estimate of the internal velocity dispersion in the cluster, and,
where relevant, the effects of the depth of the cluster along the line
of sight. Internal consistency of the TGAS data is assessed.
Results: Values given for standard uncertainties are still inaccurate
and may lead to unrealistic unit-weight standard deviations of least
squares solutions for cluster parameters. Reconstructed mean cluster
parallax and proper motion values are generally in very good agreement
with earlier HIPPARCOS-based determination, although the Gaia mean
parallax for the Pleiades is a significant exception. We have no current
explanation for that discrepancy. Most clusters are observed to extend
to nearly 15 pc from the cluster centre, and it will be up to future
Gaia releases to establish whether those potential cluster-member stars
are still dynamically bound to the clusters.
Conclusions: The
Gaia DR1 provides the means to examine open clusters far beyond their
more easily visible cores, and can provide membership assessments
based on proper motions and parallaxes. A combined HR diagram shows
the same features as observed before using the HIPPARCOS data, with
clearly increased luminosities for older A and F dwarfs. Tables
D.1 to D.19 are also available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr
(http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/601/A19
Title: VizieR Online Data Catalog: Gaia DR1 open cluster members
(Gaia Collaboration+, 2017)
Authors: Gaia Collaboration; van Leeuwen F.; Vallenari, A.; Jordi,
C.; Lindegren, L.; Bastian, U.; Prusti, T.; de Bruijne, J. H. J.;
Brown, A. G. A.; Babusiaux, C.; Bailer-Jones, C. A. L.; Biermann,
M.; Evans, D. W.; Eyer, L.; Jansen, F.; Klioner, S. A.; Lammers,
U.; Luri, X.; Mignard, F.; Panem, C.; Pourbaix, D.; Randich, S.;
Sartoretti, P.; Siddiqui, H. I.; Soubiran, C.; Valette, V.; Walton,
N. A.; Aerts, C.; Arenou, F.; Cropper, M.; Drimmel, R.; Hog, E.; Katz,
D.; Lattanzi, M. G.; O'Mullane, W.; Grebel, E. K.; Holland, A. D.; Huc,
C.; Passot, X.; Perryman, M.; Bramante, L.; Cacciari, C.; Castaneda,
J.; Chaoul, L.; Cheek, N.; de Angeli, F.; Fabricius, C.; Guerra,
R.; Hernandez, J.; Jean-Antoine-Piccolo, A.; Masana, E.; Messineo,
R.; Mowlavi, N.; Nienartowicz, K.; Ordonez-Blanco, D.; Panuzzo, P.;
Portell, J.; Richards, P. J.; Riello, M.; Seabroke, G. M.; Tanga, P.;
Thevenin, F.; Torra, J.; Els, S. G.; Gracia-Abril, G.; Comoretto, G.;
Garcia-Reinaldos, M.; Lock, T.; Mercier, E.; Altmann, M.; Andrae,
R.; Astraatmadja, T. L.; Bellas-Velidis, I.; Benson, K.; Berthier,
J.; Blomme, R.; Busso, G.; Carry, B.; Cellino, A.; Clementini, G.;
Cowell, S.; Creevey, O.; Cuypers, J.; Davidson, M.; De Ridder, J.;
de Torres, A.; Delchambre, L.; Dell'Oro, A.; Ducourant, C.; Fremat,
Y.; Garcia-Torres, M.; Gosset, E.; Halbwachs, J. -L.; Hambly, N. C.;
Harrison, D. L.; Hauser, M.; Hestroffer, D.; Hodgkin, S. T.; Huckle,
H. E.; Hutton, A.; Jasniewicz, G.; Jordan, S.; Kontizas, M.; Korn,
A. J.; Lanzafame, A. C.; Manteiga, M.; Moitinho, A.; Muinonen, K.;
Osinde, J.; Pancino, E.; Pauwels, T.; Petit, J. -M.; Recio-Blanco,
A.; Robin, A. C.; Sarro, L. M.; Siopis, C.; Smith, M.; Smith, K. W.;
Sozzetti, A.; Thuillot, W.; van Reeven, W.; Viala, Y.; Abbas, U.;
Abreu Aramburu, A.; Accart, S.; Aguado, J. J.; Allan, P. M.; Allasia,
W.; Altavilla, G.; Alvarez, M. A.; Alves, J.; Anderson, R. I.; Andrei,
A. H.; Anglada Varela, E.; Antiche, E.; Antoja, T.; Anton, S.; Arcay,
B.; Bach, N.; Baker, S. G.; Balaguer-Nunez, L.; Barache, C.; Barata,
C.; Barbier, A.; Barblan, F.; Barrado, Y. Navascues D.; Barros,
M.; Barstow, M. A.; Becciani, U.; Bellazzini, M.; Bello Garcia, A.;
Belokuro, V. V.; Ben Djoya, P.; Berihuete, A.; Bianchi, L.; Bienayme,
O.; Billebaud, F.; Blagorodnova, N.; Blanco-Cuaresma, S.; Boch, T.;
Bombrun, A.; Borrachero, R.; Bouquillon, S.; Bourda, G.; Bouy, H.;
Bragaglia, A.; Breddels, M. A.; Brouillet, N.; Bruesemeister, T.;
Bucciarelli, B.; Burgess, P.; Burgon, R.; Burlacu, A.; Busonero, D.;
Buzzi, R.; Caffau, E.; Cambras, J.; Campbell, H.; Cancelliere, R.;
Cantat-Gaudin, T.; Carlucci, T.; Carrasco, J. M.; Castellani, M.;
Charlot, P.; Charnas, J.; Chiavassa, A.; Clotet, M.; Cocozza, G.;
Collins, R. S.; Costigan, G.; Crifo, F.; Cross, N. J. G.; Crosta,
M.; Crowley, C.; Dafonte, C.; Damerdji, Y.; Dapergolas, A.; David,
P.; David, M.; De Cat, P.; de Felice, F.; de Laverny, P.; de Luise,
F.; de March, R.; de Martino, D.; de Souza, R.; Debosscher, J.;
Del Pozo, E.; Delbo, M.; Delgado, A.; Delgado, H. E.; Di Matteo, P.;
Diakite, S.; Distefano, E.; Dolding, C.; Dos Anjos, S.; Drazinos, P.;
Duran, J.; Dzigan, Y.; Edvardsson, B.; Enke, H.; Evans, N. W.; Eynard
Bontemps, G.; Fabre, C.; Fabrizio, M.; Faigler, S.; Falcao, A. J.;
Farras Casas, M.; Federici, L.; Fedorets, G.; Fernandez-Hernandez,
J.; Fernique, P.; Fienga, A.; Figueras, F.; Filippi, F.; Findeisen,
K.; Fonti, A.; Fouesneau, M.; Fraile, E.; Fraser, M.; Fuchs, J.;
Gai, M.; Galleti, S.; Galluccio, L.; Garabato, D.; Garcia-Sedano,
F.; Garofalo, A.; Garralda, N.; Gavras, P.; Gerssen, J.; Geyer, R.;
Gilmore, G.; Girona, S.; Giuffrida, G.; Gomes, M.; Gonzalez-Marcos,
A.; Gonzalez-Nunez, J.; Gonzalez-Vidal, J. J.; Granvik, M.; Guerrier,
A.; Guillout, P.; Guiraud, J.; Gurpide, A.; Gutierrez-Sanchez, R.;
Guy, L. P.; Haigron, R.; Hatzidimitriou, D.; Haywood, M.; Heiter,
U.; Helmi, A.; Hobbs, D.; Hofmann, W.; Holl, B.; Holland, G.; Hunt,
J. A. S.; Hypki, A.; Icardi, V.; Irwin, M.; Jevardat de Fombelle,
G.; Jofre, P.; Jonker, P. G.; Jorissen, A.; Julbe, F.; Karampelas,
A.; Kochoska, A.; Kohley, R.; Kolenberg, K.; Kontizas, E.; Koposov,
S. E.; Kordopatis, G.; Koubsky, P.; Krone-Martins, A.; Kudryashova, M.;
Kull, I.; Bachchan, R. K.; Lacoste-Seris, F.; Lanza, A. F.; Lavigne,
J. -B.; Le Poncin-Lafitte, C.; Lebreton, Y.; Lebzelter, T.; Leccia, S.;
Lecler, C. N.; Lecoeur-Taibi, I.; Lemaitre, V.; Lenhardt, H.; Leroux,
F.; Liao, S.; Licata, E.; Lindstrom, H. E. P.; Lister, T. A.; Livanou,
E.; Lobel, A.; Loeffler, W.; Lopez, M.; Lorenz, D.; MacDonald, I.;
Magalhaes Fernandes, T.; Managau, S.; Mann, R. G.; Mantelet, G.;
Marchal, O.; Marchant, J. M.; Marconi, M.; Marinoni, S.; Marrese,
P. M.; Marschalko, G.; Marshall, D. J.; Martin-Fleitas, J. M.; Martino,
M.; Mary, N.; Matijevic, G.; Mazeh, T.; McMillan, P. J.; Messina, S.;
Michalik, D.; Millar, N. R.; Miranda, B. M. H.; Molina, D.; Molinaro,
R.; Molinaro, M.; Molnar, L.; Moniez, M.; Montegriffo, P.; Mor, R.;
Mora, A.; Morbidelli, R.; Morel, T.; Morgenthaler, S.; Morris, D.;
Mulone, A. F.; Muraveva, T.; Musella, I.; Narbonne, J.; Nelemans, G.;
Nicastro, L.; Noval, L.; Ordenovic, C.; Ordieres-Mere, J.; Osborne,
P.; Pagani, C.; Pagano, I.; Pailler, F.; Palacin, H.; Palaversa, L.;
Parsons, P.; Pecoraro, M.; Pedrosa, R.; Pentikaeinen, H.; Pichon, B.;
Piersimoni, A. M.; Pineau, F. -X.; Plachy, E.; Plum, G.; Poujoulet, E.;
Prsa, A.; Pulone, L.; Ragaini, S.; Rago, S.; Rambaux, N.; Ramos-Lerate,
M.; Ranalli, P.; Rauw, G.; Read, A.; Regibo, S.; Reyle, C.; Ribeiro,
R. A.; Rimoldini, L.; Ripepi, V.; Riva, A.; Rixon, G.; Roelens, M.;
Romero-Gomez, M.; Rowell, N.; Royer, F.; Ruiz-Dern, L.; Sadowski,
G.; Sagrista Selles, T.; Sahlmann, J.; Salgado, J.; Salguero, E.;
Sarasso, M.; Savietto, H.; Schultheis, M.; Sciacca, E.; Segol, M.;
Segovia, J. C.; Segransan, D.; Shih, I. -C.; Smareglia, R.; Smart,
R. L.; Solano, E.; Solitro, F.; Sordo, R.; Soria Nieto, S.; Souchay,
J.; Spagna, A.; Spoto, F.; Stampa, U.; Steele, I. A.; Steidelmueller,
H.; Stephenson, C. A.; Stoev, H.; Suess, F. F.; Sueveges, M.; Surdej,
J.; Szabados, L.; Szegedi-Elek, E.; Tapiador, D.; Taris, F.; Tauran,
G.; Taylor, M. B.; Teixeira, R.; Terrett, D.; Tingley, B.; Trager,
S. C.; Turon, C.; Ulla, A.; Utrilla, E.; Valentini, G.; van Elteren,
A.; van Hemelryck, E.; Vanleeuwen, M.; Varadi, M.; Vecchiato, A.;
Veljanoski, J.; Via, T.; Vicente, D.; Vogt, S.; Voss, H.; Votruba,
V.; Voutsinas, S.; Walmsley, G.; Weiler, M.; Weingrill, K.; Wevers,
T.; Wyrzykowski, L.; Yoldas, A.; Zerjal, M.; Zucker, S.; Zurbach,
C.; Zwitter, T.; Alecu, A.; Allen, M.; Allende Prieto, C.; Amorim,
A.; Anglada-Escude, G.; Arsenijevic, V.; Azaz, S.; Balm, P.; Beck,
M.; Bernstein, H. -H.; Bigot, L.; Bijaoui, A.; Blasco, C.; Bonfigli,
M.; Bono, G.; Boudreault, S.; Bressan, A.; Brown, S.; Brunet, P. -M.;
Bunclark, P.; Buonanno, R.; Butkevich, A. G.; Carret, C.; Carrion, C.;
Chemin, L.; Chereau, F.; Corcione, L.; Darmigny, E.; de Boer, K. S.;
de Teodoro, P.; de Zeeuw, P. T.; Delle Luche, C.; Domingues, C. D.;
Dubath, P.; Fodor, F.; Frezouls, B.; Fries, A.; Fustes, D.; Fyfe,
D.; Gallardo, E.; Gallegos, J.; Gardiol, D.; Gebran, M.; Gomboc, A.;
Gomez, A.; Grux, E.; Gueguen, A.; Heyrovsky, A.; Hoar, J.; Iannicola,
G.; Isasi Parache, Y.; Janotto, A. -M.; Joliet, E.; Jonckheere, A.;
Keil, R.; Kim, D. -W.; Klagyivik, P.; Klar, J.; Knude, J.; Kochukhov,
O.; Kolka, I.; Kos, J.; Kutka, A.; Lainey, V.; Lebouquin, D.; Liu,
C.; Loreggia, D.; Makarov, V. V.; Marseille, M. G.; Martayan, C.;
Martinez-Rubi, O.; Massart, B.; Meynadier, F.; Mignot, S.; Munari,
U.; Nguyen, A. -T.; Nordlander, T.; O'Flaherty, K. S.; Ocvirk, P.;
Olias Sanz, A.; Ortiz, P.; Osorio, J.; Oszkiewicz, D.; Ouzounis, A.;
Palmer, M.; Park, P.; Pasquato, E.; Peltzer, C.; Peralta, J.; Peturaud,
F.; Pieniluoma, T.; Pigozzi, E.; Poels, J.; Prat, G.; Prod'homme, T.;
Raison, F.; Rebordao, J. M.; Risquez, D.; Rocca-Volmerange, B.; Rosen,
S.; Ruiz-Fuertes, M. I.; Russo, F.; Sembay, S.; Serraller Vizcaino,
I.; Short, A.; Siebert, A.; Silva, H.; Sinachopoulos, D.; Slezak, E.;
Soffel, M.; Sosnowska, D.; Straizys, V.; Ter Linden, M.; Terrell, D.;
Theil, S.; Tiede, C.; Troisi, L.; Tsalmantza, P.; Tur, D.; Vaccari,
M.; Vachier, F.; Valles, P.; van Hamme, W.; Veltz, L.; Virtanen,
J.; Wallut, J. -M.; Wichmann, R.; Wilkinson, M. I.; Ziaeepour, H.;
Zschocke, S.
Bibcode: 2017yCat..36010019G
Altcode:
We have determined and examined the astrometric data for 19 open
clusters, ranging from the Hyades at just under 47pc to NGC 2422
at nearly 440pc. The clusters are : the Hyades, Coma Berenices, the
Pleiades, Praesepe, alpha Per, IC 2391, IC 2602, Blanco 1, NGC 2451,
NGC 6475, NGC 7092, NGC 2516, NGC 2232, IC 4665, NGC 6633, Collinder
140, NGC 2422, NGC 3532 and NGC 2547. (2 data files).
Title: White Dwarfs in Gaia Data Release 1
Authors: Jordan, S.
Bibcode: 2017ASPC..509....9J
Altcode:
On September 14, the Gaia archives opened for access to the Gaia
DR1. The catalogue with more than one billion star positions and more
than two million parallaxes and proper motions will have enormous
influence on many topics in astronomy. However, due to their extremely
blue colour, parallaxes and proper motions of only six white dwarfs
were directly measured. Tremblay et al. used these data and those
for 46 white dwarfs in binaries in order to construct an empirical
mass-radius relation. As it was the case for Hipparcos, the precision
of the data does not allow for the characterisation of hydrogen
envelope masses. With Gaia DR2 coming in late 2017 the prospects for
white dwarf research are much better.
Title: Magnetic White Dwarfs with Heavy Elements
Authors: Hardy, F.; Dufour, P.; Jordan, S.
Bibcode: 2017ASPC..509..205H
Altcode: 2016arXiv161001522H
Using our newly developed model atmosphere code appropriate for
magnetic white dwarfs with metal lines in the Paschen-Back regime, we
study various magnetic white dwarfs and explore the effects of various
parameters such as the field geometry and the convective efficiency.
Title: The Gaia DR1 mass-radius relation for white dwarfs
Authors: Tremblay, P. -E.; Gentile-Fusillo, N.; Raddi, R.; Jordan,
S.; Besson, C.; Gänsicke, B. T.; Parsons, S. G.; Koester, D.; Marsh,
T.; Bohlin, R.; Kalirai, J.; Deustua, S.
Bibcode: 2017MNRAS.465.2849T
Altcode: 2016arXiv161100629T
The Gaia Data Release 1 (DR1) sample of white dwarf parallaxes is
presented, including six directly observed degenerates and 46 white
dwarfs in wide binaries. This data set is combined with spectroscopic
atmospheric parameters to study the white dwarf mass-radius relationship
(MRR). Gaia parallaxes and G magnitudes are used to derive model
atmosphere-dependent white dwarf radii, which can then be compared to
the predictions of a theoretical MRR. We find a good agreement between
Gaia DR1 parallaxes, published effective temperatures (Teff)
and surface gravities (log g), and theoretical MRRs. As it was the
case for Hipparcos, the precision of the data does not allow for the
characterization of hydrogen envelope masses. The uncertainties on
the spectroscopic atmospheric parameters are found to dominate the
error budget and current error estimates for well-known and bright
white dwarfs may be slightly optimistic. With the much larger Gaia
DR2 white dwarf sample, it will be possible to explore the MRR over
a much wider range of mass, Teff, and spectral types.
Title: Gaia Data Release 1. Astrometry: one billion positions,
two million proper motions and parallaxes
Authors: Lindegren, L.; Lammers, U.; Bastian, U.; Hernández, J.;
Klioner, S.; Hobbs, D.; Bombrun, A.; Michalik, D.; Ramos-Lerate,
M.; Butkevich, A.; Comoretto, G.; Joliet, E.; Holl, B.; Hutton, A.;
Parsons, P.; Steidelmüller, H.; Abbas, U.; Altmann, M.; Andrei, A.;
Anton, S.; Bach, N.; Barache, C.; Becciani, U.; Berthier, J.; Bianchi,
L.; Biermann, M.; Bouquillon, S.; Bourda, G.; Brüsemeister, T.;
Bucciarelli, B.; Busonero, D.; Carlucci, T.; Castañeda, J.; Charlot,
P.; Clotet, M.; Crosta, M.; Davidson, M.; de Felice, F.; Drimmel,
R.; Fabricius, C.; Fienga, A.; Figueras, F.; Fraile, E.; Gai, M.;
Garralda, N.; Geyer, R.; González-Vidal, J. J.; Guerra, R.; Hambly,
N. C.; Hauser, M.; Jordan, S.; Lattanzi, M. G.; Lenhardt, H.; Liao,
S.; Löffler, W.; McMillan, P. J.; Mignard, F.; Mora, A.; Morbidelli,
R.; Portell, J.; Riva, A.; Sarasso, M.; Serraller, I.; Siddiqui, H.;
Smart, R.; Spagna, A.; Stampa, U.; Steele, I.; Taris, F.; Torra, J.;
van Reeven, W.; Vecchiato, A.; Zschocke, S.; de Bruijne, J.; Gracia,
G.; Raison, F.; Lister, T.; Marchant, J.; Messineo, R.; Soffel, M.;
Osorio, J.; de Torres, A.; O'Mullane, W.
Bibcode: 2016A&A...595A...4L
Altcode: 2016arXiv160904303L
Context. Gaia Data Release 1 (DR1) contains astrometric results
for more than 1 billion stars brighter than magnitude 20.7 based
on observations collected by the Gaia satellite during the first 14
months of its operational phase.
Aims: We give a brief overview
of the astrometric content of the data release and of the model
assumptions, data processing, and validation of the results.
Methods: For stars in common with the Hipparcos and Tycho-2 catalogues,
complete astrometric single-star solutions are obtained by incorporating
positional information from the earlier catalogues. For other stars only
their positions are obtained, essentially by neglecting their proper
motions and parallaxes. The results are validated by an analysis of
the residuals, through special validation runs, and by comparison with
external data.
Results: For about two million of the brighter
stars (down to magnitude 11.5) we obtain positions, parallaxes, and
proper motions to Hipparcos-type precision or better. For these stars,
systematic errors depending for example on position and colour are at
a level of ± 0.3 milliarcsecond (mas). For the remaining stars we
obtain positions at epoch J2015.0 accurate to 10 mas. Positions and
proper motions are given in a reference frame that is aligned with the
International Celestial Reference Frame (ICRF) to better than 0.1 mas at
epoch J2015.0, and non-rotating with respect to ICRF to within 0.03 mas
yr-1. The Hipparcos reference frame is found to rotate with
respect to the Gaia DR1 frame at a rate of 0.24 mas yr-1.
Conclusions: Based on less than a quarter of the nominal mission
length and on very provisional and incomplete calibrations, the quality
and completeness of the astrometric data in Gaia DR1 are far from
what is expected for the final mission products. The present results
nevertheless represent a huge improvement in the available fundamental
stellar data and practical definition of the optical reference frame.
Title: Gaia Data Release 1. Pre-processing and source list creation
Authors: Fabricius, C.; Bastian, U.; Portell, J.; Castañeda,
J.; Davidson, M.; Hambly, N. C.; Clotet, M.; Biermann, M.; Mora,
A.; Busonero, D.; Riva, A.; Brown, A. G. A.; Smart, R.; Lammers,
U.; Torra, J.; Drimmel, R.; Gracia, G.; Löffler, W.; Spagna, A.;
Lindegren, L.; Klioner, S.; Andrei, A.; Bach, N.; Bramante, L.;
Brüsemeister, T.; Busso, G.; Carrasco, J. M.; Gai, M.; Garralda, N.;
González-Vidal, J. J.; Guerra, R.; Hauser, M.; Jordan, S.; Jordi,
C.; Lenhardt, H.; Mignard, F.; Messineo, R.; Mulone, A.; Serraller,
I.; Stampa, U.; Tanga, P.; van Elteren, A.; van Reeven, W.; Voss,
H.; Abbas, U.; Allasia, W.; Altmann, M.; Anton, S.; Barache, C.;
Becciani, U.; Berthier, J.; Bianchi, L.; Bombrun, A.; Bouquillon, S.;
Bourda, G.; Bucciarelli, B.; Butkevich, A.; Buzzi, R.; Cancelliere,
R.; Carlucci, T.; Charlot, P.; Collins, R.; Comoretto, G.; Cross,
N.; Crosta, M.; de Felice, F.; Fienga, A.; Figueras, F.; Fraile, E.;
Geyer, R.; Hernandez, J.; Hobbs, D.; Hofmann, W.; Liao, S.; Licata, E.;
Martino, M.; McMillan, P. J.; Michalik, D.; Morbidelli, R.; Parsons,
P.; Pecoraro, M.; Ramos-Lerate, M.; Sarasso, M.; Siddiqui, H.; Steele,
I.; Steidelmüller, H.; Taris, F.; Vecchiato, A.; Abreu, A.; Anglada,
E.; Boudreault, S.; Cropper, M.; Holl, B.; Cheek, N.; Crowley, C.;
Fleitas, J. M.; Hutton, A.; Osinde, J.; Rowell, N.; Salguero, E.;
Utrilla, E.; Blagorodnova, N.; Soffel, M.; Osorio, J.; Vicente, D.;
Cambras, J.; Bernstein, H. -H.
Bibcode: 2016A&A...595A...3F
Altcode: 2016arXiv160904273F
Context. The first data release from the Gaia mission contains accurate
positions and magnitudes for more than a billion sources, and proper
motions and parallaxes for the majority of the 2.5 million Hipparcos
and Tycho-2 stars.
Aims: We describe three essential elements
of the initial data treatment leading to this catalogue: the image
analysis, the construction of a source list, and the near real-time
monitoring of the payload health. We also discuss some weak points
that set limitations for the attainable precision at the present stage
of the mission.
Methods: Image parameters for point sources
are derived from one-dimensional scans, using a maximum likelihood
method, under the assumption of a line spread function constant
in time, and a complete modelling of bias and background. These
conditions are, however, not completely fulfilled. The Gaia source
list is built starting from a large ground-based catalogue, but even
so a significant number of new entries have been added, and a large
number have been removed. The autonomous onboard star image detection
will pick up many spurious images, especially around bright sources,
and such unwanted detections must be identified. Another key step
of the source list creation consists in arranging the more than
1010 individual detections in spatially isolated groups
that can be analysed individually.
Results: Complete software
systems have been built for the Gaia initial data treatment, that
manage approximately 50 million focal plane transits daily, giving
transit times and fluxes for 500 million individual CCD images to
the astrometric and photometric processing chains. The software also
carries out a successful and detailed daily monitoring of Gaia health.
Title: The Gaia mission
Authors: Gaia Collaboration; Prusti, T.; de Bruijne, J. H. J.; Brown,
A. G. A.; Vallenari, A.; Babusiaux, C.; Bailer-Jones, C. A. L.;
Bastian, U.; Biermann, M.; Evans, D. W.; Eyer, L.; Jansen, F.; Jordi,
C.; Klioner, S. A.; Lammers, U.; Lindegren, L.; Luri, X.; Mignard, F.;
Milligan, D. J.; Panem, C.; Poinsignon, V.; Pourbaix, D.; Randich, S.;
Sarri, G.; Sartoretti, P.; Siddiqui, H. I.; Soubiran, C.; Valette,
V.; van Leeuwen, F.; Walton, N. A.; Aerts, C.; Arenou, F.; Cropper,
M.; Drimmel, R.; Høg, E.; Katz, D.; Lattanzi, M. G.; O'Mullane, W.;
Grebel, E. K.; Holland, A. D.; Huc, C.; Passot, X.; Bramante, L.;
Cacciari, C.; Castañeda, J.; Chaoul, L.; Cheek, N.; De Angeli, F.;
Fabricius, C.; Guerra, R.; Hernández, J.; Jean-Antoine-Piccolo,
A.; Masana, E.; Messineo, R.; Mowlavi, N.; Nienartowicz, K.;
Ordóñez-Blanco, D.; Panuzzo, P.; Portell, J.; Richards, P. J.;
Riello, M.; Seabroke, G. M.; Tanga, P.; Thévenin, F.; Torra, J.;
Els, S. G.; Gracia-Abril, G.; Comoretto, G.; Garcia-Reinaldos, M.;
Lock, T.; Mercier, E.; Altmann, M.; Andrae, R.; Astraatmadja, T. L.;
Bellas-Velidis, I.; Benson, K.; Berthier, J.; Blomme, R.; Busso,
G.; Carry, B.; Cellino, A.; Clementini, G.; Cowell, S.; Creevey, O.;
Cuypers, J.; Davidson, M.; De Ridder, J.; de Torres, A.; Delchambre,
L.; Dell'Oro, A.; Ducourant, C.; Frémat, Y.; García-Torres, M.;
Gosset, E.; Halbwachs, J. -L.; Hambly, N. C.; Harrison, D. L.;
Hauser, M.; Hestroffer, D.; Hodgkin, S. T.; Huckle, H. E.; Hutton,
A.; Jasniewicz, G.; Jordan, S.; Kontizas, M.; Korn, A. J.; Lanzafame,
A. C.; Manteiga, M.; Moitinho, A.; Muinonen, K.; Osinde, J.; Pancino,
E.; Pauwels, T.; Petit, J. -M.; Recio-Blanco, A.; Robin, A. C.; Sarro,
L. M.; Siopis, C.; Smith, M.; Smith, K. W.; Sozzetti, A.; Thuillot,
W.; van Reeven, W.; Viala, Y.; Abbas, U.; Abreu Aramburu, A.; Accart,
S.; Aguado, J. J.; Allan, P. M.; Allasia, W.; Altavilla, G.; Álvarez,
M. A.; Alves, J.; Anderson, R. I.; Andrei, A. H.; Anglada Varela, E.;
Antiche, E.; Antoja, T.; Antón, S.; Arcay, B.; Atzei, A.; Ayache, L.;
Bach, N.; Baker, S. G.; Balaguer-Núñez, L.; Barache, C.; Barata,
C.; Barbier, A.; Barblan, F.; Baroni, M.; Barrado y Navascués, D.;
Barros, M.; Barstow, M. A.; Becciani, U.; Bellazzini, M.; Bellei, G.;
Bello García, A.; Belokurov, V.; Bendjoya, P.; Berihuete, A.; Bianchi,
L.; Bienaymé, O.; Billebaud, F.; Blagorodnova, N.; Blanco-Cuaresma,
S.; Boch, T.; Bombrun, A.; Borrachero, R.; Bouquillon, S.; Bourda, G.;
Bouy, H.; Bragaglia, A.; Breddels, M. A.; Brouillet, N.; Brüsemeister,
T.; Bucciarelli, B.; Budnik, F.; Burgess, P.; Burgon, R.; Burlacu,
A.; Busonero, D.; Buzzi, R.; Caffau, E.; Cambras, J.; Campbell, H.;
Cancelliere, R.; Cantat-Gaudin, T.; Carlucci, T.; Carrasco, J. M.;
Castellani, M.; Charlot, P.; Charnas, J.; Charvet, P.; Chassat, F.;
Chiavassa, A.; Clotet, M.; Cocozza, G.; Collins, R. S.; Collins, P.;
Costigan, G.; Crifo, F.; Cross, N. J. G.; Crosta, M.; Crowley, C.;
Dafonte, C.; Damerdji, Y.; Dapergolas, A.; David, P.; David, M.; De
Cat, P.; de Felice, F.; de Laverny, P.; De Luise, F.; De March, R.;
de Martino, D.; de Souza, R.; Debosscher, J.; del Pozo, E.; Delbo, M.;
Delgado, A.; Delgado, H. E.; di Marco, F.; Di Matteo, P.; Diakite, S.;
Distefano, E.; Dolding, C.; Dos Anjos, S.; Drazinos, P.; Durán, J.;
Dzigan, Y.; Ecale, E.; Edvardsson, B.; Enke, H.; Erdmann, M.; Escolar,
D.; Espina, M.; Evans, N. W.; Eynard Bontemps, G.; Fabre, C.; Fabrizio,
M.; Faigler, S.; Falcão, A. J.; Farràs Casas, M.; Faye, F.; Federici,
L.; Fedorets, G.; Fernández-Hernández, J.; Fernique, P.; Fienga, A.;
Figueras, F.; Filippi, F.; Findeisen, K.; Fonti, A.; Fouesneau, M.;
Fraile, E.; Fraser, M.; Fuchs, J.; Furnell, R.; Gai, M.; Galleti, S.;
Galluccio, L.; Garabato, D.; García-Sedano, F.; Garé, P.; Garofalo,
A.; Garralda, N.; Gavras, P.; Gerssen, J.; Geyer, R.; Gilmore,
G.; Girona, S.; Giuffrida, G.; Gomes, M.; González-Marcos, A.;
González-Núñez, J.; González-Vidal, J. J.; Granvik, M.; Guerrier,
A.; Guillout, P.; Guiraud, J.; Gúrpide, A.; Gutiérrez-Sánchez,
R.; Guy, L. P.; Haigron, R.; Hatzidimitriou, D.; Haywood, M.; Heiter,
U.; Helmi, A.; Hobbs, D.; Hofmann, W.; Holl, B.; Holland, G.; Hunt,
J. A. S.; Hypki, A.; Icardi, V.; Irwin, M.; Jevardat de Fombelle,
G.; Jofré, P.; Jonker, P. G.; Jorissen, A.; Julbe, F.; Karampelas,
A.; Kochoska, A.; Kohley, R.; Kolenberg, K.; Kontizas, E.; Koposov,
S. E.; Kordopatis, G.; Koubsky, P.; Kowalczyk, A.; Krone-Martins, A.;
Kudryashova, M.; Kull, I.; Bachchan, R. K.; Lacoste-Seris, F.; Lanza,
A. F.; Lavigne, J. -B.; Le Poncin-Lafitte, C.; Lebreton, Y.; Lebzelter,
T.; Leccia, S.; Leclerc, N.; Lecoeur-Taibi, I.; Lemaitre, V.; Lenhardt,
H.; Leroux, F.; Liao, S.; Licata, E.; Lindstrøm, H. E. P.; Lister,
T. A.; Livanou, E.; Lobel, A.; Löffler, W.; López, M.; Lopez-Lozano,
A.; Lorenz, D.; Loureiro, T.; MacDonald, I.; Magalhães Fernandes, T.;
Managau, S.; Mann, R. G.; Mantelet, G.; Marchal, O.; Marchant, J. M.;
Marconi, M.; Marie, J.; Marinoni, S.; Marrese, P. M.; Marschalkó,
G.; Marshall, D. J.; Martín-Fleitas, J. M.; Martino, M.; Mary, N.;
Matijevič, G.; Mazeh, T.; McMillan, P. J.; Messina, S.; Mestre, A.;
Michalik, D.; Millar, N. R.; Miranda, B. M. H.; Molina, D.; Molinaro,
R.; Molinaro, M.; Molnár, L.; Moniez, M.; Montegriffo, P.; Monteiro,
D.; Mor, R.; Mora, A.; Morbidelli, R.; Morel, T.; Morgenthaler, S.;
Morley, T.; Morris, D.; Mulone, A. F.; Muraveva, T.; Musella, I.;
Narbonne, J.; Nelemans, G.; Nicastro, L.; Noval, L.; Ordénovic, C.;
Ordieres-Meré, J.; Osborne, P.; Pagani, C.; Pagano, I.; Pailler, F.;
Palacin, H.; Palaversa, L.; Parsons, P.; Paulsen, T.; Pecoraro, M.;
Pedrosa, R.; Pentikäinen, H.; Pereira, J.; Pichon, B.; Piersimoni,
A. M.; Pineau, F. -X.; Plachy, E.; Plum, G.; Poujoulet, E.; Prša,
A.; Pulone, L.; Ragaini, S.; Rago, S.; Rambaux, N.; Ramos-Lerate,
M.; Ranalli, P.; Rauw, G.; Read, A.; Regibo, S.; Renk, F.; Reylé,
C.; Ribeiro, R. A.; Rimoldini, L.; Ripepi, V.; Riva, A.; Rixon, G.;
Roelens, M.; Romero-Gómez, M.; Rowell, N.; Royer, F.; Rudolph, A.;
Ruiz-Dern, L.; Sadowski, G.; Sagristà Sellés, T.; Sahlmann, J.;
Salgado, J.; Salguero, E.; Sarasso, M.; Savietto, H.; Schnorhk, A.;
Schultheis, M.; Sciacca, E.; Segol, M.; Segovia, J. C.; Segransan,
D.; Serpell, E.; Shih, I. -C.; Smareglia, R.; Smart, R. L.; Smith,
C.; Solano, E.; Solitro, F.; Sordo, R.; Soria Nieto, S.; Souchay, J.;
Spagna, A.; Spoto, F.; Stampa, U.; Steele, I. A.; Steidelmüller, H.;
Stephenson, C. A.; Stoev, H.; Suess, F. F.; Süveges, M.; Surdej, J.;
Szabados, L.; Szegedi-Elek, E.; Tapiador, D.; Taris, F.; Tauran, G.;
Taylor, M. B.; Teixeira, R.; Terrett, D.; Tingley, B.; Trager, S. C.;
Turon, C.; Ulla, A.; Utrilla, E.; Valentini, G.; van Elteren, A.; Van
Hemelryck, E.; van Leeuwen, M.; Varadi, M.; Vecchiato, A.; Veljanoski,
J.; Via, T.; Vicente, D.; Vogt, S.; Voss, H.; Votruba, V.; Voutsinas,
S.; Walmsley, G.; Weiler, M.; Weingrill, K.; Werner, D.; Wevers, T.;
Whitehead, G.; Wyrzykowski, Ł.; Yoldas, A.; Žerjal, M.; Zucker, S.;
Zurbach, C.; Zwitter, T.; Alecu, A.; Allen, M.; Allende Prieto, C.;
Amorim, A.; Anglada-Escudé, G.; Arsenijevic, V.; Azaz, S.; Balm,
P.; Beck, M.; Bernstein, H. -H.; Bigot, L.; Bijaoui, A.; Blasco,
C.; Bonfigli, M.; Bono, G.; Boudreault, S.; Bressan, A.; Brown, S.;
Brunet, P. -M.; Bunclark, P.; Buonanno, R.; Butkevich, A. G.; Carret,
C.; Carrion, C.; Chemin, L.; Chéreau, F.; Corcione, L.; Darmigny,
E.; de Boer, K. S.; de Teodoro, P.; de Zeeuw, P. T.; Delle Luche,
C.; Domingues, C. D.; Dubath, P.; Fodor, F.; Frézouls, B.; Fries,
A.; Fustes, D.; Fyfe, D.; Gallardo, E.; Gallegos, J.; Gardiol, D.;
Gebran, M.; Gomboc, A.; Gómez, A.; Grux, E.; Gueguen, A.; Heyrovsky,
A.; Hoar, J.; Iannicola, G.; Isasi Parache, Y.; Janotto, A. -M.;
Joliet, E.; Jonckheere, A.; Keil, R.; Kim, D. -W.; Klagyivik, P.;
Klar, J.; Knude, J.; Kochukhov, O.; Kolka, I.; Kos, J.; Kutka, A.;
Lainey, V.; LeBouquin, D.; Liu, C.; Loreggia, D.; Makarov, V. V.;
Marseille, M. G.; Martayan, C.; Martinez-Rubi, O.; Massart, B.;
Meynadier, F.; Mignot, S.; Munari, U.; Nguyen, A. -T.; Nordlander,
T.; Ocvirk, P.; O'Flaherty, K. S.; Olias Sanz, A.; Ortiz, P.; Osorio,
J.; Oszkiewicz, D.; Ouzounis, A.; Palmer, M.; Park, P.; Pasquato, E.;
Peltzer, C.; Peralta, J.; Péturaud, F.; Pieniluoma, T.; Pigozzi, E.;
Poels, J.; Prat, G.; Prod'homme, T.; Raison, F.; Rebordao, J. M.;
Risquez, D.; Rocca-Volmerange, B.; Rosen, S.; Ruiz-Fuertes, M. I.;
Russo, F.; Sembay, S.; Serraller Vizcaino, I.; Short, A.; Siebert,
A.; Silva, H.; Sinachopoulos, D.; Slezak, E.; Soffel, M.; Sosnowska,
D.; Straižys, V.; ter Linden, M.; Terrell, D.; Theil, S.; Tiede,
C.; Troisi, L.; Tsalmantza, P.; Tur, D.; Vaccari, M.; Vachier, F.;
Valles, P.; Van Hamme, W.; Veltz, L.; Virtanen, J.; Wallut, J. -M.;
Wichmann, R.; Wilkinson, M. I.; Ziaeepour, H.; Zschocke, S.
Bibcode: 2016A&A...595A...1G
Altcode: 2016arXiv160904153G
Gaia is a cornerstone mission in the science programme of the
EuropeanSpace Agency (ESA). The spacecraft construction was approved
in 2006, following a study in which the original interferometric
concept was changed to a direct-imaging approach. Both the spacecraft
and the payload were built by European industry. The involvement
of the scientific community focusses on data processing for which
the international Gaia Data Processing and Analysis Consortium
(DPAC) was selected in 2007. Gaia was launched on 19 December 2013
and arrived at its operating point, the second Lagrange point of
the Sun-Earth-Moon system, a few weeks later. The commissioning
of the spacecraft and payload was completed on 19 July 2014. The
nominal five-year mission started with four weeks of special,
ecliptic-pole scanning and subsequently transferred into full-sky
scanning mode. We recall the scientific goals of Gaia and give a
description of the as-built spacecraft that is currently (mid-2016)
being operated to achieve these goals. We pay special attention to
the payload module, the performance of which is closely related to
the scientific performance of the mission. We provide a summary of
the commissioning activities and findings, followed by a description
of the routine operational mode. We summarise scientific performance
estimates on the basis of in-orbit operations. Several intermediate
Gaia data releases are planned and the data can be retrieved from the
Gaia Archive, which is available through the Gaia home page. http://www.cosmos.esa.int/gaia
Title: Gaia Data Release 1. Summary of the astrometric, photometric,
and survey properties
Authors: Gaia Collaboration; Brown, A. G. A.; Vallenari, A.; Prusti,
T.; de Bruijne, J. H. J.; Mignard, F.; Drimmel, R.; Babusiaux, C.;
Bailer-Jones, C. A. L.; Bastian, U.; Biermann, M.; Evans, D. W.;
Eyer, L.; Jansen, F.; Jordi, C.; Katz, D.; Klioner, S. A.; Lammers,
U.; Lindegren, L.; Luri, X.; O'Mullane, W.; Panem, C.; Pourbaix, D.;
Randich, S.; Sartoretti, P.; Siddiqui, H. I.; Soubiran, C.; Valette,
V.; van Leeuwen, F.; Walton, N. A.; Aerts, C.; Arenou, F.; Cropper,
M.; Høg, E.; Lattanzi, M. G.; Grebel, E. K.; Holland, A. D.; Huc,
C.; Passot, X.; Perryman, M.; Bramante, L.; Cacciari, C.; Castañeda,
J.; Chaoul, L.; Cheek, N.; De Angeli, F.; Fabricius, C.; Guerra, R.;
Hernández, J.; Jean-Antoine-Piccolo, A.; Masana, E.; Messineo, R.;
Mowlavi, N.; Nienartowicz, K.; Ordóñez-Blanco, D.; Panuzzo, P.;
Portell, J.; Richards, P. J.; Riello, M.; Seabroke, G. M.; Tanga, P.;
Thévenin, F.; Torra, J.; Els, S. G.; Gracia-Abril, G.; Comoretto,
G.; Garcia-Reinaldos, M.; Lock, T.; Mercier, E.; Altmann, M.; Andrae,
R.; Astraatmadja, T. L.; Bellas-Velidis, I.; Benson, K.; Berthier,
J.; Blomme, R.; Busso, G.; Carry, B.; Cellino, A.; Clementini, G.;
Cowell, S.; Creevey, O.; Cuypers, J.; Davidson, M.; De Ridder, J.;
de Torres, A.; Delchambre, L.; Dell'Oro, A.; Ducourant, C.; Frémat,
Y.; García-Torres, M.; Gosset, E.; Halbwachs, J. -L.; Hambly, N. C.;
Harrison, D. L.; Hauser, M.; Hestroffer, D.; Hodgkin, S. T.; Huckle,
H. E.; Hutton, A.; Jasniewicz, G.; Jordan, S.; Kontizas, M.; Korn,
A. J.; Lanzafame, A. C.; Manteiga, M.; Moitinho, A.; Muinonen, K.;
Osinde, J.; Pancino, E.; Pauwels, T.; Petit, J. -M.; Recio-Blanco,
A.; Robin, A. C.; Sarro, L. M.; Siopis, C.; Smith, M.; Smith, K. W.;
Sozzetti, A.; Thuillot, W.; van Reeven, W.; Viala, Y.; Abbas, U.;
Abreu Aramburu, A.; Accart, S.; Aguado, J. J.; Allan, P. M.; Allasia,
W.; Altavilla, G.; Álvarez, M. A.; Alves, J.; Anderson, R. I.; Andrei,
A. H.; Anglada Varela, E.; Antiche, E.; Antoja, T.; Antón, S.; Arcay,
B.; Bach, N.; Baker, S. G.; Balaguer-Núñez, L.; Barache, C.; Barata,
C.; Barbier, A.; Barblan, F.; Barrado y Navascués, D.; Barros, M.;
Barstow, M. A.; Becciani, U.; Bellazzini, M.; Bello García, A.;
Belokurov, V.; Bendjoya, P.; Berihuete, A.; Bianchi, L.; Bienaymé,
O.; Billebaud, F.; Blagorodnova, N.; Blanco-Cuaresma, S.; Boch, T.;
Bombrun, A.; Borrachero, R.; Bouquillon, S.; Bourda, G.; Bouy, H.;
Bragaglia, A.; Breddels, M. A.; Brouillet, N.; Brüsemeister, T.;
Bucciarelli, B.; Burgess, P.; Burgon, R.; Burlacu, A.; Busonero, D.;
Buzzi, R.; Caffau, E.; Cambras, J.; Campbell, H.; Cancelliere, R.;
Cantat-Gaudin, T.; Carlucci, T.; Carrasco, J. M.; Castellani, M.;
Charlot, P.; Charnas, J.; Chiavassa, A.; Clotet, M.; Cocozza, G.;
Collins, R. S.; Costigan, G.; Crifo, F.; Cross, N. J. G.; Crosta, M.;
Crowley, C.; Dafonte, C.; Damerdji, Y.; Dapergolas, A.; David, P.;
David, M.; De Cat, P.; de Felice, F.; de Laverny, P.; De Luise, F.;
De March, R.; de Martino, D.; de Souza, R.; Debosscher, J.; del Pozo,
E.; Delbo, M.; Delgado, A.; Delgado, H. E.; Di Matteo, P.; Diakite, S.;
Distefano, E.; Dolding, C.; Dos Anjos, S.; Drazinos, P.; Duran, J.;
Dzigan, Y.; Edvardsson, B.; Enke, H.; Evans, N. W.; Eynard Bontemps,
G.; Fabre, C.; Fabrizio, M.; Faigler, S.; Falcão, A. J.; Farràs
Casas, M.; Federici, L.; Fedorets, G.; Fernández-Hernández, J.;
Fernique, P.; Fienga, A.; Figueras, F.; Filippi, F.; Findeisen, K.;
Fonti, A.; Fouesneau, M.; Fraile, E.; Fraser, M.; Fuchs, J.; Gai, M.;
Galleti, S.; Galluccio, L.; Garabato, D.; García-Sedano, F.; Garofalo,
A.; Garralda, N.; Gavras, P.; Gerssen, J.; Geyer, R.; Gilmore,
G.; Girona, S.; Giuffrida, G.; Gomes, M.; González-Marcos, A.;
González-Núñez, J.; González-Vidal, J. J.; Granvik, M.; Guerrier,
A.; Guillout, P.; Guiraud, J.; Gúrpide, A.; Gutiérrez-Sánchez,
R.; Guy, L. P.; Haigron, R.; Hatzidimitriou, D.; Haywood, M.; Heiter,
U.; Helmi, A.; Hobbs, D.; Hofmann, W.; Holl, B.; Holland, G.; Hunt,
J. A. S.; Hypki, A.; Icardi, V.; Irwin, M.; Jevardat de Fombelle,
G.; Jofré, P.; Jonker, P. G.; Jorissen, A.; Julbe, F.; Karampelas,
A.; Kochoska, A.; Kohley, R.; Kolenberg, K.; Kontizas, E.; Koposov,
S. E.; Kordopatis, G.; Koubsky, P.; Krone-Martins, A.; Kudryashova, M.;
Kull, I.; Bachchan, R. K.; Lacoste-Seris, F.; Lanza, A. F.; Lavigne,
J. -B.; Le Poncin-Lafitte, C.; Lebreton, Y.; Lebzelter, T.; Leccia, S.;
Leclerc, N.; Lecoeur-Taibi, I.; Lemaitre, V.; Lenhardt, H.; Leroux, F.;
Liao, S.; Licata, E.; Lindstrøm, H. E. P.; Lister, T. A.; Livanou,
E.; Lobel, A.; Löffler, W.; López, M.; Lorenz, D.; MacDonald, I.;
Magalhães Fernandes, T.; Managau, S.; Mann, R. G.; Mantelet, G.;
Marchal, O.; Marchant, J. M.; Marconi, M.; Marinoni, S.; Marrese,
P. M.; Marschalkó, G.; Marshall, D. J.; Martín-Fleitas, J. M.;
Martino, M.; Mary, N.; Matijevič, G.; Mazeh, T.; McMillan, P. J.;
Messina, S.; Michalik, D.; Millar, N. R.; Miranda, B. M. H.; Molina,
D.; Molinaro, R.; Molinaro, M.; Molnár, L.; Moniez, M.; Montegriffo,
P.; Mor, R.; Mora, A.; Morbidelli, R.; Morel, T.; Morgenthaler, S.;
Morris, D.; Mulone, A. F.; Muraveva, T.; Musella, I.; Narbonne, J.;
Nelemans, G.; Nicastro, L.; Noval, L.; Ordénovic, C.; Ordieres-Meré,
J.; Osborne, P.; Pagani, C.; Pagano, I.; Pailler, F.; Palacin, H.;
Palaversa, L.; Parsons, P.; Pecoraro, M.; Pedrosa, R.; Pentikäinen,
H.; Pichon, B.; Piersimoni, A. M.; Pineau, F. -X.; Plachy, E.;
Plum, G.; Poujoulet, E.; Prša, A.; Pulone, L.; Ragaini, S.; Rago,
S.; Rambaux, N.; Ramos-Lerate, M.; Ranalli, P.; Rauw, G.; Read, A.;
Regibo, S.; Reylé, C.; Ribeiro, R. A.; Rimoldini, L.; Ripepi, V.;
Riva, A.; Rixon, G.; Roelens, M.; Romero-Gómez, M.; Rowell, N.; Royer,
F.; Ruiz-Dern, L.; Sadowski, G.; Sagristà Sellés, T.; Sahlmann, J.;
Salgado, J.; Salguero, E.; Sarasso, M.; Savietto, H.; Schultheis, M.;
Sciacca, E.; Segol, M.; Segovia, J. C.; Segransan, D.; Shih, I. -C.;
Smareglia, R.; Smart, R. L.; Solano, E.; Solitro, F.; Sordo, R.;
Soria Nieto, S.; Souchay, J.; Spagna, A.; Spoto, F.; Stampa, U.;
Steele, I. A.; Steidelmüller, H.; Stephenson, C. A.; Stoev, H.;
Suess, F. F.; Süveges, M.; Surdej, J.; Szabados, L.; Szegedi-Elek,
E.; Tapiador, D.; Taris, F.; Tauran, G.; Taylor, M. B.; Teixeira, R.;
Terrett, D.; Tingley, B.; Trager, S. C.; Turon, C.; Ulla, A.; Utrilla,
E.; Valentini, G.; van Elteren, A.; Van Hemelryck, E.; van Leeuwen,
M.; Varadi, M.; Vecchiato, A.; Veljanoski, J.; Via, T.; Vicente, D.;
Vogt, S.; Voss, H.; Votruba, V.; Voutsinas, S.; Walmsley, G.; Weiler,
M.; Weingrill, K.; Wevers, T.; Wyrzykowski, Ł.; Yoldas, A.; Žerjal,
M.; Zucker, S.; Zurbach, C.; Zwitter, T.; Alecu, A.; Allen, M.; Allende
Prieto, C.; Amorim, A.; Anglada-Escudé, G.; Arsenijevic, V.; Azaz, S.;
Balm, P.; Beck, M.; Bernstein, H. -H.; Bigot, L.; Bijaoui, A.; Blasco,
C.; Bonfigli, M.; Bono, G.; Boudreault, S.; Bressan, A.; Brown, S.;
Brunet, P. -M.; Bunclark, P.; Buonanno, R.; Butkevich, A. G.; Carret,
C.; Carrion, C.; Chemin, L.; Chéreau, F.; Corcione, L.; Darmigny,
E.; de Boer, K. S.; de Teodoro, P.; de Zeeuw, P. T.; Delle Luche,
C.; Domingues, C. D.; Dubath, P.; Fodor, F.; Frézouls, B.; Fries,
A.; Fustes, D.; Fyfe, D.; Gallardo, E.; Gallegos, J.; Gardiol, D.;
Gebran, M.; Gomboc, A.; Gómez, A.; Grux, E.; Gueguen, A.; Heyrovsky,
A.; Hoar, J.; Iannicola, G.; Isasi Parache, Y.; Janotto, A. -M.;
Joliet, E.; Jonckheere, A.; Keil, R.; Kim, D. -W.; Klagyivik, P.;
Klar, J.; Knude, J.; Kochukhov, O.; Kolka, I.; Kos, J.; Kutka, A.;
Lainey, V.; LeBouquin, D.; Liu, C.; Loreggia, D.; Makarov, V. V.;
Marseille, M. G.; Martayan, C.; Martinez-Rubi, O.; Massart, B.;
Meynadier, F.; Mignot, S.; Munari, U.; Nguyen, A. -T.; Nordlander,
T.; Ocvirk, P.; O'Flaherty, K. S.; Olias Sanz, A.; Ortiz, P.; Osorio,
J.; Oszkiewicz, D.; Ouzounis, A.; Palmer, M.; Park, P.; Pasquato, E.;
Peltzer, C.; Peralta, J.; Péturaud, F.; Pieniluoma, T.; Pigozzi, E.;
Poels, J.; Prat, G.; Prod'homme, T.; Raison, F.; Rebordao, J. M.;
Risquez, D.; Rocca-Volmerange, B.; Rosen, S.; Ruiz-Fuertes, M. I.;
Russo, F.; Sembay, S.; Serraller Vizcaino, I.; Short, A.; Siebert,
A.; Silva, H.; Sinachopoulos, D.; Slezak, E.; Soffel, M.; Sosnowska,
D.; Straižys, V.; ter Linden, M.; Terrell, D.; Theil, S.; Tiede,
C.; Troisi, L.; Tsalmantza, P.; Tur, D.; Vaccari, M.; Vachier, F.;
Valles, P.; Van Hamme, W.; Veltz, L.; Virtanen, J.; Wallut, J. -M.;
Wichmann, R.; Wilkinson, M. I.; Ziaeepour, H.; Zschocke, S.
Bibcode: 2016A&A...595A...2G
Altcode: 2016arXiv160904172G
Context. At about 1000 days after the launch of Gaia we present
the first Gaia data release, Gaia DR1, consisting of astrometry and
photometry for over 1 billion sources brighter than magnitude 20.7.
Aims: A summary of Gaia DR1 is presented along with illustrations
of the scientific quality of the data, followed by a discussion of
the limitations due to the preliminary nature of this release.
Methods: The raw data collected by Gaia during the first 14 months of
the mission have been processed by the Gaia Data Processing and Analysis
Consortium (DPAC) and turned into an astrometric and photometric
catalogue.
Results: Gaia DR1 consists of three components: a
primary astrometric data set which contains the positions, parallaxes,
and mean proper motions for about 2 million of the brightest stars
in common with the Hipparcos and Tycho-2 catalogues - a realisation
of the Tycho-Gaia Astrometric Solution (TGAS) - and a secondary
astrometric data set containing the positions for an additional 1.1
billion sources. The second component is the photometric data set,
consisting of mean G-band magnitudes for all sources. The G-band light
curves and the characteristics of 3000 Cepheid and RR Lyrae stars,
observed at high cadence around the south ecliptic pole, form the third
component. For the primary astrometric data set the typical uncertainty
is about 0.3 mas for the positions and parallaxes, and about 1 mas
yr-1 for the proper motions. A systematic component of 0.3
mas should be added to the parallax uncertainties. For the subset of
94 000 Hipparcos stars in the primary data set, the proper motions are
much more precise at about 0.06 mas yr-1. For the secondary
astrometric data set, the typical uncertainty of the positions is 10
mas. The median uncertainties on the mean G-band magnitudes range from
the mmag level to 0.03 mag over the magnitude range 5 to 20.7.
Conclusions: Gaia DR1 is an important milestone ahead of the next Gaia
data release, which will feature five-parameter astrometry for all
sources. Extensive validation shows that Gaia DR1 represents a major
advance in the mapping of the heavens and the availability of basic
stellar data that underpin observational astrophysics. Nevertheless,
the very preliminary nature of this first Gaia data release does lead
to a number of important limitations to the data quality which should
be carefully considered before drawing conclusions from the data.
Title: Stellar Archaeology with Gaia: The Galactic White Dwarf
Population
Authors: Gänsicke, B.; Tremblay, P.; Barstow, M.; Bono, G.; Burleigh,
M.; Casewell, S.; Dhillon, V.; Farihi, J.; Garcia-Berro, E.; Geier,
S.; Gentile-Fusillo, N.; Hermes, J.; Hollands, M.; Istrate, A.; Jordan,
S.; Knigge, C.; Manser, C.; Marsh, T.; Nelemans, G.; Pala, A.; Raddi,
R.; Tauris, T.; Toloza, O.; Veras, D.; Werner, K.; Wilson, D.
Bibcode: 2016ASPC..507..159G
Altcode:
Gaia will identify several 105 white dwarfs, most of
which will be in the solar neighborhood at distances of a few hundred
parsecs. Ground-based optical follow-up spectroscopy of this sample
of stellar remnants is essential to unlock the enormous scientific
potential it holds for our understanding of stellar evolution, and
the Galactic formation history of both stars and planets.
Title: VizieR Online Data Catalog: New white dwarf stars in SDSS DR10
(Kepler+, 2015)
Authors: Kepler, S. O.; Pelisoli, I.; Koester, D.; Ourique, G.;
Kleinman, S. J.; Romero, A. D.; Nitta, A.; Eisenstein, D. J.;
Costa, J. E. S.; Kulebi, B.; Jordan, S.; Dufour, P.; Giommi, P.;
Rebassa-mansergas, A.
Bibcode: 2015yCat..74464078K
Altcode:
The targeted white dwarfs were required to be point sources with clean
photometry, and to have USNO-B Catalog counterparts (Monet et al.. 2003,
Cat. I/284). They were also restricted to regions inside the DR7 imaging
footprint and required to have colours within the ranges g<19.2,
(u-r)<0.4, -1<(u-g)<0.3, -1<(g-r)<0.5 and to have
low Galactic extinction Ar<0.5mag. Additionally, targets that did
not have (u-r)<-0.1 and (g-r)<-0.1 were required to have USNO
proper motions larger than 2 arcsec per century. Objects satisfying the
selection criteria that had not been observed previously by the SDSS
were denoted by the WHITEDWARF_NEW target flag, while those with prior
SDSS spectra are assigned the WHITEDWARF_SDSS flag. Some of the latter
were re-observed with BOSS in order to obtain the extended wavelength
coverage that the BOSS spectrograph offers. (1 data file).
Title: New White Dwarfs in the SDSS DR10
Authors: Kepler, S. O.; Pelisoli, I.; Koester, D.; Ourique, G.;
Kleinman, S. J.; Romero, A. D.; Nitta, A.; Eisenstein, D. J.;
Costa, J. E. S.; Külebi, B.; Jordan, S.; Dufour, P.; Giommi, P.;
Rebassa-Mansergas, A.
Bibcode: 2015ASPC..493..449K
Altcode:
We report the discovery of 8 991 new spectroscopically confirmed white
dwarfs and subdwarfs in the Sloan Digital Sky Survey Data Release
10. We obtain Teff, log g and mass for hydrogen atmosphere
white dwarf stars (DAs) and helium atmosphere white dwarf stars (DBs),
and estimate the calcium/helium abundances for the white dwarf stars
with metallic lines (DZs) and carbon/helium for cool carbon dominated
spectra DQs. We found 2 new oxygen dominated spectra white dwarfs, 69
DQs, 42 hot DO/PG1159s, 175 white dwarf+main sequence star binaries,
206 magnetic DAHs, 325 continuum dominated DCs, 397 metal polluted
white dwarfs, 450 helium dominated white dwarfs, 636 subdwarfs and
6796 new hydrogen dominated white dwarf stars.
Title: Magnetic Atmosphere Models for White Dwarfs with Heavy Elements
Authors: Dufour, Patrick; Jordan, S.; Blouin, S.; Tardif, F.; Groulx,
J.; Kilic, M.; Gianninas, A.; Barber, S. D.; Gilligan, C.
Bibcode: 2015ASPC..493...37D
Altcode:
We present selected results from our new code developed to produce
synthetic spectra for highly magnetic white dwarfs with heavy
elements. We solve the polarized radiative transfer equations and
include line splitting of heavy elements (C, O, Ca, Mg and Na in
particular) in the Paschen-Back (PB) regime for various magnetic
field geometries. Application to magnetic Hot DQ and DZ white dwarfs
are presented.
Title: New white dwarf stars in the Sloan Digital Sky Survey Data
Release 10
Authors: Kepler, S. O.; Pelisoli, I.; Koester, D.; Ourique, G.;
Kleinman, S. J.; Romero, A. D.; Nitta, A.; Eisenstein, D. J.;
Costa, J. E. S.; Külebi, B.; Jordan, S.; Dufour, P.; Giommi, Paolo;
Rebassa-Mansergas, Alberto
Bibcode: 2015MNRAS.446.4078K
Altcode: 2014arXiv1411.4149K
We report the discovery of 9088 new spectroscopically confirmed
white dwarfs and subdwarfs in the Sloan Digital Sky Survey Data
Release 10. We obtain Teff, log g and mass for hydrogen
atmosphere white dwarf stars (DAs) and helium atmosphere white dwarf
stars (DBs), and estimate the calcium/helium abundances for the
white dwarf stars with metallic lines (DZs) and carbon/helium for
carbon-dominated spectra DQs. We found 1 central star of a planetary
nebula, 2 new oxygen spectra on helium atmosphere white dwarfs, 71
DQs, 42 hot DO/PG1159s, 171 white dwarf+main-sequence star binaries,
206 magnetic DAHs, 327 continuum-dominated DCs, 397 metal-polluted
white dwarfs, 450 helium-dominated white dwarfs, 647 subdwarfs and
6887 new hydrogen-dominated white dwarf stars.
Title: White paper: Gaia and the end states of stellar evolution
Authors: Barstow, M. A; Casewell, S. L.; Catalan, S.; Copperwheat, C.;
Gaensicke, B.; Garcia-Berro, E.; Hambly, N.; Heber, U.; Holberg, J.;
Isern, J.; Jeffery, S.; Jordan, S.; Lawrie, K. A.; Lynas-Gray, A. E.;
Maccarone, T.; Marsh, T.; Parsons, S.; Silvotti, R.; Subasavage, J.;
Torres, S.; Wheatley, P.
Bibcode: 2014arXiv1407.6163B
Altcode:
This is the product of a Gaia GREAT workshop on "Gaia and the end states
of stellar evolution" held at the University of Leicester in April 2011.
Title: De Sitter universe from causal dynamical triangulations
without preferred foliation
Authors: Jordan, S.; Loll, R.
Bibcode: 2013PhRvD..88d4055J
Altcode: 2013arXiv1307.5469J
We present a detailed analysis of a recently introduced version of
causal dynamical triangulations that does not rely on a distinguished
time slicing. Focusing on the case of 2+1 spacetime dimensions, we
analyze its geometric and causal properties, present details of the
numerical setup, and explain how to extract “volume profiles.”
Extensive Monte Carlo measurements of the system show the emergence
of a de Sitter universe on large scales from the underlying quantum
ensemble, similar to what was observed previously in standard causal
dynamical triangulation quantum gravity. This provides evidence that
the distinguished time slicing of the latter is not an essential part
of its kinematical setup.
Title: Causal Dynamical Triangulations without preferred foliation
Authors: Jordan, S.; Loll, R.
Bibcode: 2013PhLB..724..155J
Altcode: 2013arXiv1305.4582J
We introduce a generalized version of the Causal Dynamical
Triangulations (CDT) formulation of quantum gravity, in which the
regularized, triangulated path integral histories maintain their causal
properties, but do not have a preferred proper-time foliation. An
extensive numerical study of the associated nonperturbative path
integral in 2 + 1 dimensions shows that it can nevertheless reproduce
the emergence of an extended de Sitter universe on large scales, a
key feature of CDT quantum gravity. This suggests that the preferred
foliation normally used in CDT is not a crucial (albeit convenient)
part of its background structure.
Title: The progenitors of magnetic white dwarfs in open clusters
Authors: Külebi, B.; Kalirai, J.; Jordan, S.; Euchner, F.
Bibcode: 2013A&A...554A..18K
Altcode: 2013arXiv1304.7171K
Context. White dwarfs are the final stages of stellar evolution for
most stars in the galaxy and magnetic white dwarfs (MWDs) represent at
least ten percent of the whole sample. According to the fossil-field
hypothesis magnetic fields are remnants of the previous stages of
evolution. However, population synthesis calculations are unable to
reproduce the MWD sample without binary interaction or inclusion of
a population of progenitor with unobservable small-scale fields.
Aims: One necessary ingredient in population synthesis is the
initial-to-final-mass relation (IFMR) which describes the mass-loss
processes during the stellar evolution. When white dwarfs are members
of open clusters, their evolutionary histories can be assessed through
the use of cluster properties. This enables an independent way of
determining the mass of their progenitors. The discovery of the
magnetic WD 0836+201 in the Praesepe cluster prompted the question
whether magnetic fields affect the IFMR. In this work we investigate
this suggestion through investigations of all three known MWDs in
open clusters.
Methods: We assess the cluster membership by
correlating the proper-motion of MWDs with the cluster proper-motion
and by analyzing the candidates spectroscopically with our magnetic
model spectra in order to estimate the effective temperature and
radii. Furthermore, we use mass-radius relations and evolutionary models
to constrain the histories of the probable cluster members.
Results: We identified SDSS J085523.87+164059.0 to be a proper-motion
member of Praesepe. We also included the data of the formerly identified
cluster members NGC 6819-8, WD 0836+201 and estimated the mass, cooling
age and the progenitor masses of the three probable MWD members of open
clusters. According to our analysis, the newly identified cluster member
SDSS J085523.87+164059.0 is an ultra-massive MWD of mass 1.12 ± 0.11
M⊙.
Conclusions: We increase the sample of MWDs
with known progenitor masses to ten, with the rest of the data coming
from the common proper motion binaries. Our investigations show that,
when effects of the magnetic fields are included in the diagnostics,
the estimated properties of these cluster MWDs do not show evidence
for deviations from the IFMR. Furthermore we estimate the precision
of the magnetic diagnostics which would be necessary to determine
quantitatively whether magnetism has any effect on the mass-loss.
Title: Magnetic white dwarf stars in the Sloan Digital Sky Survey
Authors: Kepler, S. O.; Pelisoli, I.; Jordan, S.; Kleinman, S. J.;
Koester, D.; Külebi, B.; Peçanha, V.; Castanheira, B. G.; Nitta,
A.; Costa, J. E. S.; Winget, D. E.; Kanaan, A.; Fraga, L.
Bibcode: 2013MNRAS.429.2934K
Altcode: 2012arXiv1211.5709K; 2013MNRAS.tmp..506K
To obtain better statistics on the occurrence of magnetism among white
dwarfs, we searched the spectra of the hydrogen atmosphere white dwarf
stars (DAs) in the Data Release 7 of the Sloan Digital Sky Survey
(SDSS) for Zeeman splittings and estimated the magnetic fields. We
found 521 DAs with detectable Zeeman splittings, with fields in the
range from around 1 to 733 MG, which amounts to 4 per cent of all
DAs observed. As the SDSS spectra have low signal-to-noise ratios,
we carefully investigated by simulations with theoretical spectra how
reliable our detection of magnetic field was.
Title: Quantum spacetime, from a practitioner's point of view
Authors: Ambjørn, J.; Jordan, S.; Jurkiewicz, J.; Loll, R.
Bibcode: 2013AIPC.1514...60A
Altcode: 2013arXiv1302.2181A
We argue that theories of quantum gravity constructed with the
help of (Causal) Dynamical Triangulations have given us the most
informative, quantitative models to date of quantum spacetime. Most
importantly, these are derived dynamically from nonperturbative
and background-independent quantum theories of geometry. In the
physically relevant case of four spacetime dimensions, the ansatz
of Causal Dynamical Triangulations produces - from a fairly minimal
set of quantum field-theoretic inputs - an emergent spacetime which
macroscopically looks like a de Sitter universe, and on Planckian scales
possesses unexpected quantum properties. Important in deriving these
results are a regularized version of the theory, in which the quantum
dynamics is well defined, can be studied with the help of numerical
Monte Carlo methods and extrapolated to infinite lattice volumes.
Title: Low Magnetic Fields in White Dwarfs and their Direct
Progenitors?
Authors: Jordan, S.; Bagnulo, S.; Landstreet, J.; Fossati, L.;
Valyavin, G. G.; Monin, D.; Wade, G. A.; Werner, K.; O'Toole, S. J.
Bibcode: 2013ASPC..469..411J
Altcode: 2012arXiv1210.3987J
We have carried out a re-analysis of polarimetric data of central stars
of planetary nebulae, hot subdwarfs, and white dwarfs taken with FORS1
(FOcal Reducer and low dispersion Spectrograph) on the VLT (Very Large
Telescope), and added a large number of new observations in order to
increase the sample. A careful analysis of the observations using only
one wavelength calibration for the polarimetrically analysed spectra
and for all positions of the retarder plate of the spectrograph is
crucial in order to avoid spurious signals. We find that the previous
detections of magnetic fields in subdwarfs and central stars could
not be confirmed while about 10% of the observed white dwarfs have
magnetic fields at the kilogauss level.
Title: The Hubble Exoplanet Classroom
Authors: Stevens, Laura; Carson, J.; Ruwadi, D.; Low, K.; Jordan,
S.; Schneider, G.
Bibcode: 2013AAS...22124605S
Altcode:
We present a status report on the Hubble Exoplanet Classroom,
an interactive website designed to engage 8-12th grade students
in physical science concepts using the exciting field of exoplanet
studies. Addressing national teaching standards, the webpage allows
educators to enhance their physical science, physics, and astronomy
curriculum with student-driven lessons. The webpage records students'
performance on lessons and quizzes and compiles the results, which
can be accessed by the instructor using a secure website.
Title: White Dwarfs Escaping From the Hyades
Authors: Tremblay, P. -E.; Schilbach, E.; Röser, S.; Jordan, S.;
Ludwig, H. -G.; Goldman, B.
Bibcode: 2013ASPC..469..105T
Altcode:
Ten white dwarfs are currently known to be associated with the
Hyades cluster. This number of degenerate objects is too low when
compared to the predictions of numerical simulations. Using the PPMXL
catalog of proper motions and positions, 17 new Hyades white dwarf
candidates have recently been proposed, most of them outside of the
tidal radius. They could potentially explain the discrepancy between
the observed and predicted number of associated objects. We review
the Hyades membership of these candidates by using spectroscopic and
photometric observations, as well as by simulating the contamination
from field white dwarfs. We find that six objects remain candidates,
and three more objects have an uncertain membership status due to
their unknown or imprecise atmospheric parameters.
Title: High-field magnetic white dwarfs as the progeny of early-type
stars?
Authors: Dobbie, P. D.; Külebi, B.; Casewell, S. L.; Burleigh, M. R.;
Parker, Q. A.; Baxter, R.; Lawrie, K. A.; Jordan, S.; Koester, D.
Bibcode: 2013MNRAS.428L..16D
Altcode: 2012MNRAS.tmpL...4D
We present an analysis of the newly resolved components of
two hot, double-degenerate systems, SDSS J074853.07+302543.5 +
J074852.95+302543.4 and SDSS J150813.24+394504.9 + J150813.31+394505.6
(CBS 229). We confirm that each system has widely separated components
(a > 100 au) consisting of a H-rich, non-magnetic white dwarf and
a H-rich, high-field magnetic white dwarf (HFMWD). The masses of the
non-magnetic degenerates are found to be larger than typical of field
white dwarfs. We use these components to estimate the total ages of
the binaries and demonstrate that both magnetic white dwarfs are the
progeny of stars with Minit > 2 M⊙. We
briefly discuss the traits of all known hot, wide, magnetic +
non-magnetic double degenerates in the context of HFMWD formation
theories. These are broadly consistent (chance probability, P ≈ 0.065)
with HFMWDs forming primarily from early-type stars and, in the most
succinct interpretation, link their magnetism to the fields of their
progenitors. Our results do not, however, rule out that HFMWDs can
form through close binary interactions and studies of more young,
wide double degenerates are required to reach firm conclusions on
these formation pathways.
Title: Astrometric Determination of White Dwarf Radial Velocities
with Gaia?
Authors: Jordan, S.; de Bruijne, J.
Bibcode: 2013ASPC..469..257J
Altcode: 2012arXiv1210.3983J
Usually, the determination of radial velocities of stars relies on the
shift of spectral lines by the Doppler effect. Russel & Atkinson
(1931) and Oort (1932) already noted that due to the large proper motion
and parallax of the white dwarf (WD) van Maanen 2, a determination
of the perspective acceleration of the proper motion would provide
a direct astrometric determination of the radial velocity which is
independent of the gravitational redshift. If spectroscopic redshift
measurements of Halpha and Hbeta NLTE cores exist, a purely astrometric
determination would allow disentangling the gravitational redshift
from the Doppler shift. The best instrument for measuring the tiny
perspective acceleration is the Gaia satellite of the European Space
Agency, aiming at absolute astrometric measurements of one billion stars
down to 20th magnitude with unprecedented accuracy. At 15th magnitude,
the predicted angular accuracy of Gaia is about 20 micro-arcseconds. In
this article, we estimate whether it is possible to measure the radial
velocity of WDs astrometrically by the exchange of proper motion
into radial velocity during the 5-year mission of the satellite or by
combining Hipparcos data with the position measurements at the beginning
of the Gaia mission (the Hundred-Thousand-Proper-Motion project HTPM).
Title: Spectroscopic and photometric studies of white dwarfs in
the Hyades
Authors: Tremblay, P. -E.; Schilbach, E.; Röser, S.; Jordan, S.;
Ludwig, H. -G.; Goldman, B.
Bibcode: 2012A&A...547A..99T
Altcode: 2012arXiv1209.4309T
The Hyades cluster is known to harbour ten so-called classical white
dwarf members. Numerous studies through the years have predicted
that more than twice this amount of degenerate stars should be
associated with the cluster. Using the PPMXL Catalog of proper
motions and positions, a recent study proposed 17 new white dwarf
candidates. We review the membership of these candidates by using
published spectroscopic and photometric observations, as well as by
simulating the contamination from field white dwarfs. In addition to
the ten classical Hyades white dwarfs, we find six white dwarfs that
may be of Hyades origin and three more objects that have an uncertain
membership status due to their unknown or imprecise atmospheric
parameters. Among those, two to three are expected as field stars
contamination. Accurate radial velocity measurements will confirm or
reject the candidates. One consequence is that the longstanding problem
that no white dwarf older than ~340 Myr appears to be associated with
the cluster remains unsolved.
Title: On the incidence of weak magnetic fields in DA white dwarfs
Authors: Landstreet, J. D.; Bagnulo, S.; Valyavin, G. G.; Fossati,
L.; Jordan, S.; Monin, D.; Wade, G. A.
Bibcode: 2012A&A...545A..30L
Altcode: 2012arXiv1208.3650L
Context. About 10% of white dwarfs have magnetic fields with strength
in the range between about 105 and 5 × 108 G. It
is not known whether the remaining white dwarfs are not magnetic, or if
they have magnetic fields too weak to be detected with the techniques
adopted in the large surveys. Information is particularly lacking
for the cooler (and generally fainter) white dwarfs.
Aims:
We describe the results of the first survey specifically devised to
clarify the detection frequency of kG-level magnetic fields in cool DA
white dwarfs.
Methods: Using the FORS1 instrument of the ESO VLT,
we have obtained Balmer line circular spectropolarimetric measurements
of a small sample of cool (DA6 - DA8) white dwarfs. Using FORS and
UVES archive data, we have also revised numerous white dwarf field
measurements previously published in the literature.
Results:
We have discovered an apparently constant longitudinal magnetic field of
~9.5 kG in the DA6 white dwarf WD 2105-820. This star
is the first weak-field white dwarf that has been observed sufficiently
to roughly determine the characteristics of its field. The available
data are consistent with a simple dipolar morphology with magnetic
axis nearly parallel to the rotation axis, and a polar strength
of ≃ 56 kG. Our re-evaluation of the FORS archive data for white
dwarfs indicates that longitudinal magnetic fields weaker than 10
kG have previously been correctly identified in at least three white
dwarfs. However, for one of these three weak-field stars (WD
2359-434), UVES archive data show a ~100 kG mean field
modulus. Either at the time of the FORS observations the star's
magnetic field axis was nearly perpendicular to the line of sight,
or the star's magnetic field has rather complex structure.
Conclusions: We find that the probability of detecting a field of kG
strength in a DA white dwarf is of the order of 10% for each of the
cool and hot DA stars. If there is a lower cutoff to field strength
in white dwarfs, or a field below which all white dwarfs are magnetic,
the current precision of measurements is not yet sufficient to reveal
it. Based on observations collected at the European Organisation
for Astronomical Research in the Southern Hemisphere, Chile, under
observing programme 073.D-0516, and obtained from the ESO/ST-ECF
Science Archive Facility.Table 3 is available in electronic form at
http://www.aanda.org
Title: Magnetic fields in central stars of planetary nebulae?
Authors: Jordan, S.; Bagnulo, S.; Werner, K.; O'Toole, S. J.
Bibcode: 2012A&A...542A..64J
Altcode: 2012arXiv1204.2697J
Context. Most planetary nebulae have bipolar or other non-spherically
symmetric shapes. Magnetic fields in the central star may be responsible
for this lack of symmetry, but observational studies published to
date have reported contradictory results.
Aims: We search for
correlations between a magnetic field and departures from the spherical
geometry of the envelopes of planetary nebulae.
Methods: We
determine the magnetic fields from spectropolarimetric observations of
ten central stars of planetary nebulae. The results of the analysis of
the observations of four stars were previously presented and discussed
in the literature, while the observations of six stars, plus additional
measurements of a star previously observed, are presented here for
the first time.
Results: All our determinations of magnetic
field in the central planetary nebulae are consistent with null
results. Our field measurements have a typical error bar of 150-300
G. Previous spurious field detections using data acquired with FORS1
(FOcal Reducer and low dispersion Spectrograph) of the Unit Telescope 1
(UT1) of the Very Large Telescope (VLT) were probably due to the use
of different wavelength calibration solutions for frames obtained at
different position angles of the retarder waveplate.
Conclusions:
There is currently no observational evidence of magnetic fields with
a strength of the order of hundreds Gauss or higher in the central
stars of planetary nebulae. Based on observations collected at
the European Organisation for Astronomical Research in the Southern
Hemisphere, Chile, under programme ID 072.D-0089 (PI = Jordan) and
075.D-0289 (PI = Jordan).
Title: Second- and first-order phase transitions in causal dynamical
triangulations
Authors: Ambjørn, Jan; Jordan, S.; Jurkiewicz, J.; Loll, R.
Bibcode: 2012PhRvD..85l4044A
Altcode: 2012arXiv1205.1229A
Causal dynamical triangulations (CDT) is a proposal for a theory of
quantum gravity, which implements a path-integral quantization of
gravity as the continuum limit of a sum over piecewise flat spacetime
geometries. We use Monte Carlo simulations to analyze the phase
transition lines bordering the physically interesting de Sitter phase
of the four-dimensional CDT model. Using a range of numerical criteria,
we present strong evidence that the so-called A-C transition is first
order, while the B-C transition is second order. The presence of a
second-order transition may be related to an ultraviolet fixed point
of quantum gravity and thus provide the key to probing physics at and
possibly beyond the Planck scale.
Title: The magnetic fields of hot subdwarf stars
Authors: Landstreet, J. D.; Bagnulo, S.; Fossati, L.; Jordan, S.;
O'Toole, S. J.
Bibcode: 2012A&A...541A.100L
Altcode: 2012arXiv1203.6815L
Context. Detection of magnetic fields has been reported in several sdO
and sdB stars. Recent literature has cast doubts on the reliability of
most of these detections. The situation concerning the occurrence and
frequency of magnetic fields in hot subdwarfs is at best confused.
Aims: We revisit data previously published in the literature, and
we present new observations to clarify the question of how common
magnetic fields are in subdwarf stars.
Methods: We consider
a sample of about 40 hot subdwarf stars. About 30 of them have been
observed with the FORS1 and FORS2 instruments of the ESO VLT. Results
have been published for only about half of the hot subdwarfs observed
with FORS. Here we present new FORS1 field measurements for 17 stars,
14 of which have never been observed for magnetic fields before. We also
critically review the measurements already published in the literature,
and in particular we try to explain why previous papers based on the
same FORS1 data have reported contradictory results.
Results:
All new and re-reduced measurements obtained with FORS1 are shown to be
consistent with non-detection of magnetic fields. We explain previous
spurious field detections from data obtained with FORS1 as due to
a non-optimal method of wavelength calibration. Field detections in
other surveys are found to be uncertain or doubtful, and certainly in
need of confirmation.
Conclusions: There is presently no strong
evidence for the occurrence of a magnetic field in any sdB or sdO star,
with typical longitudinal field uncertainties of the order of 2-400
G. It appears that globally simple fields of more than about 1 or 2 kG
in strength occur in at most a few percent of hot subdwarfs. Further
high-precision surveys, both with high-resolution spectropolarimeters
and with instruments similar to FORS1 on large telescopes, would be
very valuable. Based on observations collected at the European
Organisation for Astronomical Research in the Southern Hemisphere,
Chile under observing programmes 072.D-0290 and 075.D-0352, or obtained
from the ESO/ST-ECF Science Archive Facility.
Title: The Gaia-ESO Public Spectroscopic Survey
Authors: Gilmore, G.; Randich, S.; Asplund, M.; Binney, J.; Bonifacio,
P.; Drew, J.; Feltzing, S.; Ferguson, A.; Jeffries, R.; Micela, G.;
Negueruela, I.; Prusti, T.; Rix, H. -W.; Vallenari, A.; Alfaro, E.;
Allende-Prieto, C.; Babusiaux, C.; Bensby, T.; Blomme, R.; Bragaglia,
A.; Flaccomio, E.; François, P.; Irwin, M.; Koposov, S.; Korn, A.;
Lanzafame, A.; Pancino, E.; Paunzen, E.; Recio-Blanco, A.; Sacco,
G.; Smiljanic, R.; Van Eck, S.; Walton, N.; Aden, D.; Aerts, C.;
Affer, L.; Alcala, J. -M.; Altavilla, G.; Alves, J.; Antoja, T.;
Arenou, F.; Argiroffi, C.; Asensio Ramos, A.; Bailer-Jones, C.;
Balaguer-Nunez, L.; Bayo, A.; Barbuy, B.; Barisevicius, G.; Barrado
y Navascues, D.; Battistini, C.; Bellas Velidis, I.; Bellazzini, M.;
Belokurov, V.; Bergemann, M.; Bertelli, G.; Biazzo, K.; Bienayme, O.;
Bland-Hawthorn, J.; Boeche, C.; Bonito, S.; Boudreault, S.; Bouvier,
J.; Brandao, I.; Brown, A.; de Bruijne, J.; Burleigh, M.; Caballero,
J.; Caffau, E.; Calura, F.; Capuzzo-Dolcetta, R.; Caramazza, M.;
Carraro, G.; Casagrande, L.; Casewell, S.; Chapman, S.; Chiappini,
C.; Chorniy, Y.; Christlieb, N.; Cignoni, M.; Cocozza, G.; Colless,
M.; Collet, R.; Collins, M.; Correnti, M.; Covino, E.; Crnojevic,
D.; Cropper, M.; Cunha, M.; Damiani, F.; David, M.; Delgado, A.;
Duffau, S.; Edvardsson, B.; Eldridge, J.; Enke, H.; Eriksson, K.;
Evans, N. W.; Eyer, L.; Famaey, B.; Fellhauer, M.; Ferreras, I.;
Figueras, F.; Fiorentino, G.; Flynn, C.; Folha, D.; Franciosini,
E.; Frasca, A.; Freeman, K.; Fremat, Y.; Friel, E.; Gaensicke, B.;
Gameiro, J.; Garzon, F.; Geier, S.; Geisler, D.; Gerhard, O.; Gibson,
B.; Gomboc, A.; Gomez, A.; Gonzalez-Fernandez, C.; Gonzalez Hernandez,
J.; Gosset, E.; Grebel, E.; Greimel, R.; Groenewegen, M.; Grundahl,
F.; Guarcello, M.; Gustafsson, B.; Hadrava, P.; Hatzidimitriou, D.;
Hambly, N.; Hammersley, P.; Hansen, C.; Haywood, M.; Heber, U.; Heiter,
U.; Held, E.; Helmi, A.; Hensler, G.; Herrero, A.; Hill, V.; Hodgkin,
S.; Huelamo, N.; Huxor, A.; Ibata, R.; Jackson, R.; de Jong, R.;
Jonker, P.; Jordan, S.; Jordi, C.; Jorissen, A.; Katz, D.; Kawata,
D.; Keller, S.; Kharchenko, N.; Klement, R.; Klutsch, A.; Knude,
J.; Koch, A.; Kochukhov, O.; Kontizas, M.; Koubsky, P.; Lallement,
R.; de Laverny, P.; van Leeuwen, F.; Lemasle, B.; Lewis, G.; Lind,
K.; Lindstrom, H. P. E.; Lobel, A.; Lopez Santiago, J.; Lucas, P.;
Ludwig, H.; Lueftinger, T.; Magrini, L.; Maiz Apellaniz, J.; Maldonado,
J.; Marconi, G.; Marino, A.; Martayan, C.; Martinez-Valpuesta, I.;
Matijevic, G.; McMahon, R.; Messina, S.; Meyer, M.; Miglio, A.;
Mikolaitis, S.; Minchev, I.; Minniti, D.; Moitinho, A.; Momany, Y.;
Monaco, L.; Montalto, M.; Monteiro, M. J.; Monier, R.; Montes, D.;
Mora, A.; Moraux, E.; Morel, T.; Mowlavi, N.; Mucciarelli, A.; Munari,
U.; Napiwotzki, R.; Nardetto, N.; Naylor, T.; Naze, Y.; Nelemans, G.;
Okamoto, S.; Ortolani, S.; Pace, G.; Palla, F.; Palous, J.; Parker, R.;
Penarrubia, J.; Pillitteri, I.; Piotto, G.; Posbic, H.; Prisinzano,
L.; Puzeras, E.; Quirrenbach, A.; Ragaini, S.; Read, J.; Read, M.;
Reyle, C.; De Ridder, J.; Robichon, N.; Robin, A.; Roeser, S.; Romano,
D.; Royer, F.; Ruchti, G.; Ruzicka, A.; Ryan, S.; Ryde, N.; Santos,
N.; Sanz Forcada, J.; Sarro Baro, L. M.; Sbordone, L.; Schilbach, E.;
Schmeja, S.; Schnurr, O.; Schoenrich, R.; Scholz, R. -D.; Seabroke, G.;
Sharma, S.; De Silva, G.; Smith, M.; Solano, E.; Sordo, R.; Soubiran,
C.; Sousa, S.; Spagna, A.; Steffen, M.; Steinmetz, M.; Stelzer, B.;
Stempels, E.; Tabernero, H.; Tautvaisiene, G.; Thevenin, F.; Torra,
J.; Tosi, M.; Tolstoy, E.; Turon, C.; Walker, M.; Wambsganss, J.;
Worley, C.; Venn, K.; Vink, J.; Wyse, R.; Zaggia, S.; Zeilinger, W.;
Zoccali, M.; Zorec, J.; Zucker, D.; Zwitter, T.; Gaia-ESO Survey Team
Bibcode: 2012Msngr.147...25G
Altcode:
The Gaia-ESO Public Spectroscopic Survey has begun and will obtain high
quality spectroscopy of some 100000 Milky Way stars, in the field and
in open clusters, down to magnitude 19, systematically covering all the
major components of the Milky Way. This survey will provide the first
homogeneous overview of the distributions of kinematics and chemical
element abundances in the Galaxy. The motivation, organisation and
implementation of the Gaia-ESO Survey are described, emphasising the
complementarity with the ESA Gaia mission. Spectra from the very first
observing run of the survey are presented.
Title: Two new young, wide, magnetic + non-magnetic double-degenerate
binary systems
Authors: Dobbie, P. D.; Baxter, R.; Külebi, B.; Parker, Q. A.;
Koester, D.; Jordan, S.; Lodieu, N.; Euchner, F.
Bibcode: 2012MNRAS.421..202D
Altcode: 2011arXiv1111.7015D
We report the discovery of two, new, rare, wide, double-degenerate
binaries that each contain a magnetic and a non-magnetic star. The
components of SDSS J092646.88+132134.5 + J092647.00+132138.4 and of SDSS
J150746.48+521002.1 + J150746.80+520958.0 have angular separations
of only 4.6 arcsec (a∼ 650 au) and 5.1 arcsec (a∼ 750 au),
respectively. They also appear to share common proper motions. Follow-up
optical spectroscopy has revealed each system to consist of a DA and a
H-rich high-field magnetic white dwarf (HFMWD). Our measurements of the
effective temperatures and the surface gravities of the DA components
reveal both to have larger masses than is typical of field white
dwarfs. By assuming that these degenerates have evolved essentially
as single stars, owing to their wide orbital separations, we can use
them to place limits on the total ages of the stellar systems. These
suggest that in each case the HFMWD is probably associated with an
early-type progenitor (Minit > 2 M⊙). We
find that the cooling time of SDSS J150746.80+520958.0 (DAH) is
lower than might be expected had it followed the evolutionary path
of a typical single star. This mild discord is in the same sense
as that observed for two of the small number of other HFMWDs for
which progenitor mass estimates have been made, RE J0317-853 and EG
59. The mass of the other DAH, SDSS J092646.88+132134.5, appears to be
smaller than expected on the basis of single-star evolution. If this
object was/is a member of a hierarchical triple system it may have
experienced greater mass loss during an earlier phase of its life as
a result of its having a close companion. The large uncertainties on
our estimates of the parameters of the HFMWDs suggest that a larger
sample of these objects is required to firmly identify any trends in
their inferred cooling times and progenitor masses. This should shed
further light on their formation and on the impact magnetic fields
have on the late stages of stellar evolution. To serve as a starting
point, we highlight two further candidate young, wide magnetic +
non-magnetic double-degenerate systems within SDSS, CBS 229 and SDSS
J074853.07+302543.5 + J074852.95+302543.4, which should be subjected
to detailed (resolved) spectroscopic follow-up studies.
Title: Second-Order Phase Transition in Causal Dynamical
Triangulations
Authors: Ambjørn, Jan; Jordan, S.; Jurkiewicz, J.; Loll, R.
Bibcode: 2011PhRvL.107u1303A
Altcode: 2011arXiv1108.3932A
Causal dynamical triangulations are a concrete attempt to define a
nonperturbative path integral for quantum gravity. We present strong
evidence that the lattice theory has a second-order phase transition
line, which can potentially be used to define a continuum limit in
the conventional sense of nongravitational lattice theories.
Title: Constraints on the origin of the massive, hot, and rapidly
rotating magnetic white dwarf RE J 0317-853 from an HST parallax
measurement
Authors: Külebi, B.; Jordan, S.; Nelan, E.; Bastian, U.; Altmann, M.
Bibcode: 2010A&A...524A..36K
Altcode: 2010arXiv1007.4978K
Aims: We use the parallax measurements of RE J 0317-853 to
determine its mass, radius, and cooling age and thereby constrain
its evolutionary origins.
Methods: We observed RE J 0317-853
with the Hubble Space Telescope's Fine Guidance Sensor to measure the
parallax of RE J 0317-853 and its binary companion, the non-magnetic
white dwarf LB 9802. In addition, we acquired spectra of comparison
stars with the Boller & Chivens spectrograph of the SMARTS
telescope to correct the parallax zero point. For the corrected
parallax, we determine the radius, mass, and the cooling age with
the help of evolutionary models from the literature.
Results:
The properties of RE J 0317-853 are constrained using the parallax
information. We discuss the different cases of the core composition
and the uncertain effective temperature. We confirm that RE J 0317-853
is close to the Chandrasekhar's mass limit in all cases and almost
as old as its companion LB 9802.
Conclusions: The precise
evolutionary history of RE J 0317-853 depends on our knowledge of
its effective temperature. It is possible that it had a single star
progenitor possible if we assume that the effective temperature is
at the cooler end of the possible range from 30 000 to 50 000 K; if
Teff is instead at the hotter end, a binary-merger scenario
for RE J 0317-853 becomes more plausible. Based on observations
made with the NASA/ESA Hubble Space Telescope, obtained at the Space
Telescope Science Institute, which is operated by the Association
of Universities for Research in Astronomy, Inc., under NASA contract
NAS5-26555. The Guide Star Catalogue-II is a joint project of the Space
Telescope Science Institute and the Osservatorio Astronomico di Torino.
Title: Evolutionary Status of REJ 0317-853
Authors: Külebi, B.; Jordan, S.; Nelan, E.; Burleigh, M.; Bastian,
U.; Altmann, M.; Euchner, F.
Bibcode: 2010AIPC.1273...85K
Altcode:
RE J 0317-853 is an isolated magnetic white dwarf which is hot, highly
magnetized and rapidly rotating compared to the rest of the magnetic
white dwarf population. Due to an alleged age discrepancy estimated by
its hot nature and his colder binary counterpart LB 9802, RE J 0317-853
was assumed to be a result of a binary merger. In this work we present
the parallax measurements made with the Hubble Space Telescope's Fine
Guidance System and the spectro-polarimetry from Anglo-Australian
Observatory in order to reassess the evolutionary history of the binary
system. Through the parallax measurement we determine the radius,
mass and, furthermore, with the use of evolutionary models from the
literature we estimate the cooling age. Additionally, we modelled the
phase resolved flux and polarisation spectra of RE J 0317-853 and for
the first time our magnetic models are able to account for the formerly
unexplained feature with 16% of circular polarisation. We also discuss
the effect of different possible core compositions and the effect of
the uncertainty of the effective temperature; the value of the latter
is extremely important for a correct interpretation of the evolutionary
history of RE J 0317-853. A single star origin is possible if we assume
that the effective temperature is at the cooler end of the possible
range from 30000 K to 50000 K; if Teff is rather at the hotter end,
a binary merger scenario for RE J 0317-853 becomes more plausible.
Title: Complexity of the Gaia astrometric least-squares problem and
the (non-)feasibility of a direct solution method
Authors: Bombrun, A.; Lindegren, L.; Holl, B.; Jordan, S.
Bibcode: 2010A&A...516A..77B
Altcode:
The Gaia space astrometry mission (to be launched in 2012) will use
a continuously spinning spacecraft to construct a global system of
positions, proper motions and absolute parallaxes from relative position
measurements made in an astrometric focal plane. This astrometric
reduction can be cast as a classical least-squares problem, and the
adopted baseline method for its solution uses a simple iteration
algorithm. A potential weakness of this approach, as opposed to a
direct solution, is that any finite number of iterations results in
truncation errors that are difficult to quantify. Thus it is of interest
to investigate alternative approaches, in particular the feasibility
of a direct (non-iterative) solution. A simplified version of the
astrometric reduction problem is studied in which the only unknowns are
the astrometric parameters for a subset of the stars and the continuous
three-axis attitude, thus neglecting further calibration issues. The
specific design of the Gaia spacecraft and scanning law leads to an
extremely large and sparse normal equations matrix. Elimination of the
star parameters leads to a much smaller but less sparse system. We try
different reordering schemes and perform symbolic Cholesky decomposition
of this reduced normal matrix to study the fill-in for successively
longer time span of simulated observations. Extrapolating to the full
mission length, we conclude that a direct solution is not feasible with
today's computational capabilities. Other schemes, e.g., eliminating
the attitude parameters or orthogonalizing the observation equations,
lead to similar or even worse problems. This negative result appears to
be a consequence of the strong spatial and temporal connectivity among
the unknowns achieved by two superposed fields of view and the scanning
law, features that are in fact desirable and essential for minimizing
large-scale systematic errors in the Gaia reference frame. We briefly
consider also an approximate decomposition method à la Hipparcos,
but conclude that it is either sub-optimal or effectively leads to an
iterative solution.
Title: CDT meets Hořava-Lifshitz gravity
Authors: Ambjørn, J.; Görlich, A.; Jordan, S.; Jurkiewicz, J.;
Loll, R.
Bibcode: 2010PhLB..690..413A
Altcode: 2010arXiv1002.3298A
The theory of causal dynamical triangulations (CDT) attempts to define
a nonperturbative theory of quantum gravity as a sum over spacetime
geometries. One of the ingredients of the CDT framework is a global
time foliation, which also plays a central role in the quantum gravity
theory recently formulated by Hořava. We show that the phase diagram
of CDT bears a striking resemblance with the generic Lifshitz phase
diagram appealed to by Hořava. We argue that CDT might provide a
unifying nonperturbative framework for anisotropic as well as isotropic
theories of quantum gravity.
Title: PG1258+593 and its common proper motion magnetic white dwarf
counterpart
Authors: Girven, J.; Gänsicke, B. T.; Külebi, B.; Steeghs, D.;
Jordan, S.; Marsh, T. R.; Koester, D.
Bibcode: 2010MNRAS.404..159G
Altcode: 2010arXiv1001.1359G; 2010MNRAS.tmp..271G
We confirm SDSSJ130033.48+590407.0 as a common proper motion companion
to the well-studied hydrogen-atmosphere (DA) white dwarf PG1258+593
(GD322). The system lies at a distance of 68 +/- 3pc, where the angular
separation of 16.1 +/- 0.1arcsec corresponds to a minimum binary
separation of 1091 +/- 7au. SDSSJ1300+5904 is a cool (Teff
= 6300 +/- 300K) magnetic white dwarf (B ~= 6mG). PG1258+593 is
a DA white dwarf with Teff = 14790 +/- 77K and logg =
7.87 +/- 0.02. Using the white dwarf mass-radius relation implies
the masses of SDSSJ1300+5904 and PG1258+593 are 0.54 +/- 0.06 and
0.54 +/- 0.01Msolar, respectively, and therefore a cooling
age difference of 1.67 +/- 0.05Gyr. Adopting main-sequence lifetimes
from stellar models, we derive an upper limit of 2.2Msolar
for the mass of the progenitor of PG1258+593. A plausible range of
initial masses is 1.4-1.8 Msolar for PG1258+593 and 2-3
Msolar for SDSSJ1300+5904. Our analysis shows that white
dwarf common proper motion binaries can potentially constrain the white
dwarf initial mass-final mass relation and the formation mechanism
for magnetic white dwarfs. The magnetic field of SDSSJ1300+5904 is
consistent with an Ap progenitor star. A common envelope origin of the
system cannot be excluded, but requires a triple system as progenitor.
Title: VizieR Online Data Catalog: Magnetic fields in white dwarfs
(Kuelebi+, 2009)
Authors: Kuelebi, B.; Jordan, S.; Euchner, F.; Gaensicke, B. T.;
Hirsch, H.
Bibcode: 2010yCat..35061341K
Altcode:
We calculated a grid of state-of-the-art theoretical optical spectra of
hydrogen-rich magnetic white dwarfs (WDs) with magnetic field strengths
of between 1MG and 1200MG for different angles between the magnetic
field vector and the line of sight, and for effective temperatures
between 7000K and 50000K. We used a least squares minimization scheme
with an evolutionary algorithm to find the best-fit magnetic field
geometry of the observed data. We used centered dipoles or dipoles
that had been shifted along the dipole axis to model the coadded SDSS
fiber spectrum of each object. (1 data file).
Title: Study of short period variables and small amplitude periodic
variables
Authors: Varadi, M.; Eyer, L.; Jordan, S.; Koester, D.
Bibcode: 2010EAS....45..167V
Altcode: 2010arXiv1011.4885V; 2011EAS....45..167V
Our goal is to assess Gaia's performance on the period recovery of
short period (p < 2 hours) and small amplitude variability. To
reach this goal first we collected the properties of variable stars
that fit the requirements described above. Then we built a database of
synthetic light-curves with short period and low amplitude variability
with time sampling that follows the Gaia nominal scanning law and with
noise level corresponding to the expected photometric precision of
Gaia. Finally we performed period search on the synthetic light-curves
to obtain period recovery statistics. This work extends our previous
period recovery studies to short period variable stars which have
non-stationary Fourier spectra.
Title: Analysis of hydrogen-rich magnetic white dwarfs detected in
the Sloan Digital Sky Survey
Authors: Külebi, B.; Jordan, S.; Euchner, F.; Gänsicke, B. T.;
Hirsch, H.
Bibcode: 2009A&A...506.1341K
Altcode: 2009arXiv0907.2372K
Context: A large number of magnetic white dwarfs discovered in the SDSS
have so far only been analyzed by visual comparison of the observations
with relatively simple models of the radiation transport in a magnetised
stellar atmosphere.
Aims: We model the structure of the surface
magnetic fields of the hydrogen-rich white dwarfs in the SDSS.
Methods: We calculated a grid of state-of-the-art theoretical
optical spectra of hydrogen-rich magnetic white dwarfs (WDs) with
magnetic field strengths of between 1 MG and 1200 MG for different
angles between the magnetic field vector and the line of sight,
and for effective temperatures between 7000 K and 50 000 K. We used
a least squares minimization scheme with an evolutionary algorithm to
find the best-fit magnetic field geometry of the observed data. We used
centered dipoles or dipoles that had been shifted along the dipole axis
to model the coadded SDSS fiber spectrum of each object.
Results:
We analyzed the spectra of all known magnetic hydrogen-rich (DA) WDs
from the SDSS (97 previously published, plus 44 newly discovered) and
also investigated the statistical properties of the magnetic field
geometries of this sample.
Conclusions: The total number of
known magnetic white dwarfs has already been more than tripled by the
SDSS and more objects are expected after more systematic searches. The
magnetic fields have strengths of between ≈ 1 and 900 MG. Our results
further support the claims that Ap/Bp population is insufficient in
generating the numbers and field strength distributions of the observed
MWDs, and that of either another source of progenitor types or binary
evolution is needed. Clear indications of non-centered dipoles exist
in about ~50%, of the objects which is consistent with the magnetic
field distribution observed in Ap/Bp stars. Appendix A and Table
3 are only available in electronic form at http://www.aanda.org
Title: The Gaia project: Technique, performance and status
Authors: Jordan, S.
Bibcode: 2008AN....329..875J
Altcode: 2008arXiv0811.2345J
Gaia is a satellite mission of the ESA, aiming at absolute astrometric
measurements of about one billion stars (all stars down to 20th
magnitude, with unprecedented accuracy. Additionally, magnitudes and
colors will be obtained for all these stars, while radial-velocities
and spectral properties will be determined only for bright objects
({V<17.5}). At 15th magnitude Gaia aims at an angular accuracy
of 20 microarcseconds (\muas). This goal can only be reached if the
geometry of the telescopes, the detectors, and the pointing of Gaia at
each moment (``attitude'') can be inferred from the Gaia measurements
itself with \muas accuracy.
Title: ELSA training the next generation of space astrometrists
Authors: Lindegren, L.; Bijaoui, A.; Brown, A. G. A.; Drimmel, R.;
Eyer, L.; Jordan, S.; Kontizas, M.; van Leeuwen, F.; Muinonen, K.;
Pourbaix, D.; Torra, J.; Turon, C.; de Vries, J.; Zwitter, T.
Bibcode: 2008IAUS..248..529L
Altcode:
ELSA (European Leadership in Space Astrometry) is an EU-funded research
project 2006 2010, contributing to the scientific preparations for the
Gaia mission while training young researchers in space astrometry and
related subjects. Nine postgraduate (PhD) students and five postdocs
have been recruited to the network. Their research focuses on the
principles of global astrometric, photometric, and spectroscopic
measurements from space, instrument modelling and calibration, and
numerical analysis tools and data processing methods relevant for Gaia.
Title: The Fraction of DA White Dwarfs with Kilo--Gauss Magnetic
Fields
Authors: Jordan, S.; Aznar Cuadrado, R.; Napiwotzki, R.; Schmid,
H. M.; Solanki, S. K.
Bibcode: 2007ASPC..372..169J
Altcode: 2006astro.ph.10881J
Current estimates for white dwarfs with fields in excess of 1 MG are
about 10%; according to our first high-precision circular-polarimetric
study of 12 bright white dwarfs with the VLT tep{p26_Aznar-etal:04}
this number increases up to about 25%\ in the kG regime. With our
new sample of ten white dwarf observations (plus one sdO star) we
wanted to improve the sample statistics to determine the incident
of kG magnetic fields in white dwarfs. In one of our objects (LTT
7987) we detected a statistically significant (97% confidence level)
longitudinal magnetic field varying between (-1± 0.5) kG and (+1±
0.5) kG. This would be the weakest magnetic field ever found in a
white dwarf, but at this level of accuracy, systematic errors cannot
completely be ruled out. Together with previous investigations, the
fraction of kG magnetic fields in white dwarfs amounts to about 11-15%
, which is close to current estimates for highly magnetic white dwarfs
(>1 MG).
Title: Gaia --- A White Dwarf Discovery Machine
Authors: Jordan, S.
Bibcode: 2007ASPC..372..139J
Altcode: 2006astro.ph.10879J
Gaia is a satellite mission of the ESA, aiming at absolute astrometric
measurements of about one billion stars (V<20) with unprecedented
accuracy. Additionally, magnitudes and colors will be obtained for
all these stars, while radial-velocities will be determined only
for bright objects (V<17.5). However, the wavelength range for
the radial-velocity instrument is rather unsuitable for most white
dwarfs. Gaia will probably discover about 400,000 white dwarfs;
up to 100 pc the detection probability for white dwarfs is almost
100 %. This survey of white dwarfs will have very clear, easy to
understand selection criteria, and will therefore be very suitable
for statistical investigations. The Gaia data will help to improve
the construction of a luminosity function for the disk and the halo
and will provide a more accurate determination of the age of our solar
neighborhood. Moreover, reliable stellar dynamical investigations of the
disk and halo components will be possible. For the first time it will
be possible to test the mass-radius relation of white dwarfs in great
detail. Moreover, more accurate masses of magnetic and cool white dwarfs
can be expected. Gaia is also expected to discover many new pulsating
white dwarfs. The Gaia measurements can also complement the measurements
of gravitational waves from close white dwarf binaries with Lisa.
Title: EUNIS Results on He II 304 Å Line Formation
Authors: Jordan, S. D.; Brosius, J. W.
Bibcode: 2007ASPC..368..183J
Altcode:
The first flight of the Goddard Extreme Ultraviolet Normal Incidence
Spectrograph (EUNIS) took place from White Sands Missile Range at
18:10 UT on April 12, 2006. Observations of the He II 304 Å principal
resonance line were obtained with a cadence of ∼ 2 seconds along
an eleven arc-minute slit. Corresponding EIT images of this line, and
additional EUNIS observations of the strong coronal line of Fe XVI at
335.4 Å, were used to assess the role of the photoionizing coronal
flux in the formation of the He II line. In agreement with previous
work of these authors and others, the results support formation by the
collisional excitation mechanism by thermal electrons in the quiet Sun.
Title: The fraction of DA white dwarfs with kilo-Gauss magnetic fields
Authors: Jordan, S.; Aznar Cuadrado, R.; Napiwotzki, R.; Schmid,
H. M.; Solanki, S. K.
Bibcode: 2007A&A...462.1097J
Altcode: 2006astro.ph.10875J
Context: Weak magnetic fields have been searched for on only a small
number of white dwarfs. Current estimates find that about 10% of all
white dwarfs have fields in excess of 1 MG; according to previous
studies this number increases up to about 25% in the kG regime.
Aims: Our aim is to improve on these statistics by a new sample
of ten white dwarfs in order to determine the ratio of magnetic to
field-free white dwarfs.
Methods: Mean longitudinal magnetic
fields strengths were determined by means of high-precision circular
polarimetry of Hβ and Hγ with the FORS1 spectrograph of the VLT
"Kueyen" 8 m telescope.
Results: In one of our objects (LTT
7987), we detected a statistically significant (97% confidence level)
longitudinal magnetic field varying between (-1± 0.5) kG and (+1±
0.5) kG. This would be the weakest magnetic field ever found in a
white dwarf, but systematic errors cannot completely be ruled out at
this level of accuracy. We also observed the sdO star EC 11481-2303 but
could not detect a magnetic field.
Conclusions: . VLT observations
with uncertainties typically of 1000 G or less suggest that 15-20% of
WDs have kG fields. Together with previous investigations, the fraction
of kG magnetic fields in white dwarfs amounts to about 11-15%, which is
close to the current estimations for highly magnetic white dwarfs (>1
MG). Based on observations made with ESO Telescopes at the La Silla
or Paranal Observatories under programme ID 073.D-0356. Figures A.1
and A.2 are only available in electronic form at http://www.aanda.org
Title: Zeeman tomography of magnetic white dwarfs. IV. The complex
field structure of the polars EF Eridani, BL Hydri and CP Tucanae
Authors: Beuermann, K.; Euchner, F.; Reinsch, K.; Jordan, S.;
Gänsicke, B. T.
Bibcode: 2007A&A...463..647B
Altcode: 2006astro.ph.10804B
Context: The magnetic fields of the accreting white dwarfs in
magnetic cataclysmic variables (mCVs) determine the accretion
geometries, the emission properties, and the secular evolution of
these objects.
Aims: We determine the structure of the surface
magnetic fields of the white dwarf primaries in magnetic CVs using
Zeeman tomography.
Methods: Our study is based on orbital-phase
resolved optical flux and circular polarization spectra of the polars
EF Eri, BL Hyi, and CP
Tuc obtained with FORS1 at the ESO VLT. An evolutionary
algorithm is used to synthesize best fits to these spectra from
an extensive database of pre-computed Zeeman spectra. The general
approach has been described in previous papers of this series.
Results: The results achieved with simple geometries as centered
or offset dipoles are not satisfactory. Significantly improved fits
are obtained for multipole expansions that are truncated at degree
l_max=3 or 5 and include all tesseral and sectoral components with
0≤ m≤ l. The most frequent field strengths of 13, 18, and 10 MG for
EF Eri, BL Hyi, and CP
Tuc, and the ranges of field strength covered are similar for
the dipole and multipole models, but only the latter provide access
to accreting matter at the right locations on the white dwarf. The
results suggest that the field geometries of the white dwarfs in
short-period mCVs are quite complex, with strong contributions from
multipoles higher than the dipole in spite of a typical age of the
white dwarfs in CVs in excess of 1 Gyr.
Conclusions: .It is
feasible to derive the surface field structure of an accreting white
dwarf from phase-resolved low-state circular spectropolarimetry of
sufficiently high signal-to-noise ratio. The fact that independent
information is available on the strength and direction of the field in
the accretion spot from high-state observations helps in unraveling
the global field structure. Based on observations collected at
the European Southern Observatory, Paranal, Chile, under programme
IDs 63.P-0003(A), 64.P-0150(C), and 66.D-0128(B).
Title: Zeeman tomography of magnetic white dwarfs. III. The 70-80
Megagauss magnetic field of PG 1015+014
Authors: Euchner, F.; Jordan, S.; Beuermann, K.; Reinsch, K.;
Gänsicke, B. T.
Bibcode: 2006A&A...451..671E
Altcode: 2006astro.ph..2112E
Aims. We analyse the magnetic field geometry of the magnetic DA white
dwarf PG 1015+014 with our Zeeman tomography
method.
Methods: . This study is based on rotation-phase
resolved optical flux and circular polarization spectra of PG
1015+014 obtained with FORS1 at the ESO VLT. Our tomographic
code makes use of an extensive database of pre-computed Zeeman
spectra. The general approach has been described in Papers I and II of
this series.
Results: . The surface field strength distributions
for all rotational phases of PG 1015+014 are
characterised by a strong peak at 70 MG. A separate peak at 80
MG is seen for about one third of the rotation cycle. Significant
contributions to the Zeeman features arise from regions with field
strengths between 50 and 90 MG. We obtain equally good simultaneous
fits to the observations, collected in five phase bins, for two
different field parametrizations: (i) a superposition of individually
tilted and off-centred zonal multipole components; and (ii) a truncated
multipole expansion up to degree l = 4 including all zonal and tesseral
components. The magnetic fields generated by both parametrizations
exhibit a similar global structure of the absolute surface field values,
but differ considerably in the topology of the field lines. An effective
photospheric temperature of T_eff = 10 000 ± 1000 K was found.
Conclusions: . Remaining discrepancies between the observations and
our best-fit models suggest that additional small-scale structure of
the magnetic field exists which our field models are unable to cover
due to the restricted number of free parameters.
Title: First Results From EUNIS 2005
Authors: Rabin, D. M.; Thomas, R. J.; Davila, J. M.; Brosius, J. W.;
Swartz, M.; Jordan, S. D.
Bibcode: 2005AGUFMSH41B1122R
Altcode:
The Extreme Ultraviolet Normal-Incidence Spectrograph (EUNIS) is
a sounding rocket experiment to investigate the energetics of the
solar corona and hotter transition region through high-resolution
imaging spectroscopy with a rapid (2 second) cadence. Pre-flight
characterization of throughput has demonstrated that EUNIS is the
most sensitive solar EUV spectrograph in existence, having over
100 times the throughput of its predecessor, the Solar Extreme
ultraviolet Research Telescope and Spectrograph (SERTS). We report
initial results from the first flight in November 2005 from White
Sands Missile Range. The main scientific goal of the first EUNIS
flight is to extend the investigation of transient phenomena, such as
nanoflares and blinkers, to shorter timescales than has been possible
with previous EUV spectrographs. The two independent optical systems
of EUNIS record spatially co-aligned spectra over two passbands
(170--205 Å and 300--370 Å) simultaneously with spectral resolution
of 60 mÅ or 120 mÅ, respectively. The longwave passband includes
He II 304 Å and strong lines from Fe XI--XVI. The shortwave passband
has a sequence of very strong Fe IX--XIII lines. Together, the EUNIS
telescopes furnish a wide range of temperature and density diagnostics
and enable underflight calibration of instrumental passbands on the
SOHO, TRACE, Solar-B, and STEREO missions.
Title: Zeeman tomography of magnetic white dwarfs. II. The
quadrupole-dominated magnetic field of HE 1045-0908
Authors: Euchner, F.; Reinsch, K.; Jordan, S.; Beuermann, K.;
Gänsicke, B. T.
Bibcode: 2005A&A...442..651E
Altcode: 2005astro.ph..7631E
We report time-resolved optical flux and circular polarization
spectroscopy of the magnetic DA white dwarf HE
1045-0908 obtained with FORS1 at the ESO VLT. Considering
published results, we estimate a likely rotational period of P_rot ≃
2.7 h, but cannot exclude values as high as about 9 h. Our detailed
Zeeman tomographic analysis reveals a field structure which is
dominated by a quadrupole and contains additional dipole and octupole
contributions, and which does not depend strongly on the assumed value
of the period. A good fit to the Zeeman flux and polarization spectra
is obtained if all field components are centred and inclinations of
their magnetic axes with respect to each other are allowed for. The fit
can be slightly improved if an offset from the centre of the star is
included. The prevailing surface field strength is 16 MG, but values
between 10 and ~ 75 MG do occur. We derive an effective photospheric
temperature of HE 1045-0908 of T_eff = 10 000 ±
1000 K. The tomographic code makes use of an extensive database of
pre-computed Zeeman spectra (Paper I).
Title: On the nature of the unidentified solar emission near 117 nm
Authors: Wilhelm, K.; Schühle, U.; Curdt, W.; Hilchenbach, M.;
Marsch, E.; Lemaire, P.; Bertaux, J. -L.; Jordan, S. D.; Feldman, U.
Bibcode: 2005A&A...439..701W
Altcode:
Spectral observations of the Sun in the vacuum-ultraviolet wavelength
range by SUMER on SOHO led to the discovery of unusual emission
features - called humps here - at 116.70 nm and 117.05 nm on either
side of the He i 58.43 nm line. This resonance line is seen in the
second order of diffraction, whereas the humps are recorded in the
first order with the SUMER spectrometer. In its spectra both orders
are superimposed. Two less pronounced humps can be detected at 117.27
nm and near 117.85 nm. After rejecting various possibilities of an
instrumental cause of the humps, they are studied in different solar
regions. Most of the measurements, in particular those related to the
limb-brightening characteristics, indicate that the humps are not part
of the background continuum. An assembly of spectrally-unresolved atomic
or ionic emission lines might be contributing to the hump at 117.05
nm, but no such lines are known near 116.7 nm. It is concluded that we
detect genuine radiation, the generation of which is not understood. A
two-photon emission process, parametric frequency down conversion,
and molecular emissions are briefly considered as causes of the humps,
but a final conclusion could not be reached.
Title: The Structure and Origin of Magnetic Fields on Accreting
White Dwarfs
Authors: Reinsch, K.; Euchner, F.; Beuermann, K.; Jordan, S.;
Gänsicke, B. T.
Bibcode: 2005ASPC..330..177R
Altcode: 2004astro.ph.10144R
We have started a systematic study of the field topologies of magnetic
single and accreting white dwarfs using Zeeman tomography. Here
we report on our analysis of phase-resolved flux and circular
polarization spectra of the magnetic cataclysmic variables BL Hyi
and MR Ser obtained with FORS1 at the ESO VLT. For both systems we
find that the field topologies are more complex than a dipole or
an offset dipole and require at least multipole expansions up to
order l = 3 to adequately describe the observed Zeeman features and
their variations with rotational phase. Overall our model fits are in
excellent agreement with observations. Remaining residuals indicate
that the field topologies might even be more complex. It is, however,
assuring that the global characteristics of our solutions are consistent
with the average effective field strengths and the halo field strengths
derived from intensity spectra in the past.
Title: Kilo-Gauss Magnetic Fields in Three DA White Dwarfs
Authors: Aznar Cuadrado, R.; Jordan, S.; Napiwotzki, R.; Schmid,
H. M.; Solanki, S. K.; Mathys, G.
Bibcode: 2005ASPC..334..159A
Altcode: 2005astro.ph..1191A; 2005astro.ph..1191C
We have detected longitudinal magnetic fields between 2 and 4 kG in
three normal DA white dwarfs (WD 0446-790, WD 1105-048, WD 2359-434)
out of a sample of 12 by using optical spectropolarimetry done with
the VLT Antu 8 m telescope equipped with FORS1. With the exception of
40 Eri B (4 kG) these are the first positive detections of magnetic
fields in white dwarfs below 30 kG. A detection rate of 25 % (3/12)
may indicate now for the first time that a substantial fraction of
white dwarfs have weak magnetic fields. This result, if confirmed by
future observations, would form a cornerstone for our understanding
of the evolution of stellar magnetic fields.
Title: Discovery of Magnetic Fields in Hot Subdwarfs
Authors: O'Toole, S. J.; Jordan, S.; Friedrich, S.; Heber, U.
Bibcode: 2005ASPC..334..261O
Altcode: 2004astro.ph.10042O
We present initial results of a project to measure mean longitudinal
magnetic fields in a group of sdB/OB/O stars. The project was
inspired by the discovery of three super-metal-rich sdOB stars, each
having metals (e.g. Ti, V) enhanced by factors of 103
to 105. Similar behaviour is observed in chemically
peculiar A stars, where strong magnetic fields are responsible for the
enrichment. With this in mind, we obtained circularly polarised spectra
of two of the super-metal-rich sdOBs, two "normal" sdBs and two sdOs
using FORS1 on the ESO/VLT. By examining circular polarisation in the
hydrogen Balmer lines and in helium lines, we have detected magnetic
fields with strengths of 1-2 kG in most of our targets. This suggests
that such fields are relatively common in hot subdwarfs.
Title: Constraining Gravitational Theories by Observing Magnetic
White Dwarfs
Authors: Preuss, O.; Jordan, S.; Haugan, M. P.; Solanki, S. K.
Bibcode: 2005ASPC..334..265P
Altcode: 2004astro.ph.11688P
Under the assumption of a specific nonminimal coupling of torsion
to electromagnetism, spacetime is birefringent in the presence of a
gravitational field leading to depolarization of light emitted from
extended astrophysical sources. We use polarimetric data of the magnetic
white dwarf RE J0317-853 to set for the very first time constraints on
the essential coupling constant for this effect, giving k2
∼ (22 m)2.
Title: Surface Magnetic Field Distributions of the White Dwarfs PG
1015+014 and HE 1045-0908
Authors: Euchner, F.; Jordan, S.; Reinsch, K.; Beuermann, K.;
Gänsicke, B. T.
Bibcode: 2005ASPC..334..269E
Altcode: 2004astro.ph.10199E
We have applied the method of Zeeman tomography to analyze the surface
magnetic field structures of the white dwarfs PG 1015+014 and HE
1045-0908 from spin-phase resolved flux and circular polarization
spectra obtained with FORS1 at the ESO VLT. We find for both objects
field topologies that deviate significantly from centred dipoles. For
HE 1045-0908, the frequency distribution of magnetic field strengths
is sharply peaked at 16 MG for all rotational phases covered by our
data but extends to field strengths at least five times this value. In
the case of PG 1015+014 there are significant contributions to the
frequency distribution in the range from 50 to 90 MG with the maximum
near 70 MG. The detailed shape of the frequency distribution is strongly
variable with respect to the rotational phase.
Title: Discovery of Magnetic Fields in CPNs
Authors: Jordan, S.; Werner, K.; O'Toole, S. J.
Bibcode: 2005ASPC..334..257J
Altcode: 2004astro.ph.10509J
For the first time we have directly detected magnetic fields in central
stars of planetary nebulae by means of spectro-polarimetry with FORS1 at
the VLT. In all four objects of our sample we found kilogauss magnetic
fields, in NGC 1360 and LSS 1362 with very high significance, while in
Abell 36 and EGB 5 the existence of a magnetic field is probable but
with less certainty. This discovery supports the hypothesis that the
non-spherical symmetry of most planetary nebulae is caused by magnetic
fields in AGB stars. Our high discovery rate demands mechanisms to
prevent full conservation of magnetic flux during the transition to
white dwarfs.
Title: Discovery of magnetic fields in hot subdwarfs
Authors: O'Toole, S. J.; Jordan, S.; Friedrich, S.; Heber, U.
Bibcode: 2005A&A...437..227O
Altcode: 2005astro.ph..3243O
We present polarisation measurements of sdB and sdO stars using FORS1
on the VLT. The observations were made as part of a project to determine
whether magnetic fields in two super-metal-rich stars can explain their
extreme abundance peculiarities. Field strengths of up to ~1.5 kG range
have been measured at varying levels of significance in each of our six
targets, however no clear evidence was found between apparently normal
subdwarfs and the metal-rich objects. The origin of the magnetic fields
is unknown. We also discuss the implications of our measurements for
magnetic flux conservation in late stages of stellar evolution.
Title: Do Magnetic Fields Prevent Hydrogen from Accreting onto Cool
Metal-line White Dwarf Stars?
Authors: Friedrich, S.; Jordan, S.; Koester, D.
Bibcode: 2005ASPC..334..273F
Altcode: 2004astro.ph.10507F
It is generally assumed that metals detected in the spectra of a few
cool white dwarfs cannot be of primordial origin and must be accreted
from the interstellar medium. However, the observed abundances of
hydrogen, which should also be accreted from the interstellar medium,
are lower than expected from metal accretion. Magnetic fields are
thought to be the reason for this discrepancy. We have therefore
obtained circular polarization spectra of the helium-rich white dwarfs
GD 40 and L745-46A, which both show strong metal lines as well as
hydrogen. Whereas L745-46A might have a magnetic field of about -6900
G, which is about two times the field strength of 3000 G necessary to
repell hydrogen at the Alfén radius, only an upper limit for the field
strength of GD 40 of 4000 G (with 99% confidence) can be set which is
far off the minimum field strength of 144000 G to repell hydrogen.
Title: Discovery of magnetic fields in central stars of planetary
nebulae
Authors: Jordan, S.; Werner, K.; O'Toole, S. J.
Bibcode: 2005A&A...432..273J
Altcode: 2005astro.ph..1040J
For the first time we have directly detected magnetic fields in central
stars of planetary nebulae by means of spectro-polarimetry with FORS1 at
the VLT. In all four objects of our sample we found kilogauss magnetic
fields, in NGC 1360 and LSS 1362 with very high significance, while
in EGB 5 and Abell 36 the existence of a magnetic field is probable
but with less certainty. This discovery supports the hypothesis that the
non-spherical symmetry of most planetary nebulae is caused by magnetic
fields in AGB stars. Our high discovery rate demands mechanisms to
prevent full conservation of magnetic flux during the transition to
white dwarfs. Based on observations collected at the European
Southern Observatory, Paranal, Chile, under programme ID 072.D-0089.
Title: Gaia First Look
Authors: Jordan, S.; Bastian, U.; Lenhardt, H.; Bernstein, H. -H.;
Hirte, S.; Biermann, M.
Bibcode: 2005ESASP.576..405J
Altcode: 2004astro.ph.11227J; 2005tdug.conf..405J
A complicated and ambitious space mission like Gaia needs a careful
monitoring and evaluation of the functioning of all components of
the satellite. This has to be performed on different time scales,
by different methods, and on different levels of precision. On the
basis of housekeeping data a Quick Look will be performed by the ground
segment. A first analyses of the science data quality and consistency
will be done by a Science Quick Look. However, due to the nominal
scanning law a full self-consistent calibration of the satellite, and
a determination of astrometric and global parameters, is not possible
before about half a year has elapsed, imposing a serious danger to
lose valuable observing time if something goes wrong. Therefore, it
is absolutely necessary to perform a Detailed First Look on a daily
basis on the µas accuracy level. We describe two different methods,
a block iterative procedure and a direct solution, to monitor all
satellite parameters that in principle can be evaluated within a short
amount of time, particularly those that can be measured in along-scan
direction. This first astrometric analysis would greatly benefit from
a modified scanning law (Zero-nu-dot mode) for some time during the
commissioning phase.
Title: Magnetic Field Topology of Accreting White Dwarfs
Authors: Reinsch, K.; Euchner, F.; Beuermann, K.; Jordan, S.
Bibcode: 2004ASPC..315...71R
Altcode: 2003astro.ph..2056R; 2004IAUCo.190...71R
We report first results of our systematic investigation of the magnetic
field structure of rotating single magnetic white dwarfs and of white
dwarfs in magnetic cataclysmic variables. The global magnetic field
distributions on the isolated white dwarf HE1045-0908 and the accreting
white dwarfs in EF Eri and CP Tuc have been derived from phase-resolved
flux and polarization spectra obtained with FORS1 at the ESO VLT using
the systematic method of Zeeman tomography.
Title: A 150 MG Magnetic White Dwarf in the Cataclysmic Variable
RX J1554.2+2721
Authors: Gänsicke, B. T.; Jordan, S.; Beuermann, K.; de Martino,
D.; Szkody, P.; Marsh, T. R.; Thorstensen, J.
Bibcode: 2004ApJ...613L.141G
Altcode: 2004astro.ph..8301G
We report the detection of Zeeman-split Lyα absorption π
and σ+ lines in the far-ultraviolet Hubble Space
Telescope/Space Telescope Imaging Spectrograph (STIS) spectrum of
the magnetic cataclysmic variable RX J1554.2+2721. Fitting the
STIS data with magnetic white dwarf model spectra, we derive a
field strength of B~=144 MG and an effective temperature of 17,000
K<~Teff<~23,000 K. This measurement makes RX
J1554.2+2721 only the third cataclysmic variable containing a white
dwarf with a field exceeding 100 MG. Similar to the other high-field
polar AR UMa, RX J1554.2+2721 is often found in a state of feeble mass
transfer, which suggests that a considerable number of high-field polars
may still remain undiscovered. Based on observations made with
the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope
Science Institute, which is operated by the Association of Universities
for Research in Astronomy, Inc., under NASA contract NAS 5-26555.
Title: Discovery of kilogauss magnetic fields in three DA white dwarfs
Authors: Aznar Cuadrado, R.; Jordan, S.; Napiwotzki, R.; Schmid,
H. M.; Solanki, S. K.; Mathys, G.
Bibcode: 2004A&A...423.1081A
Altcode: 2004astro.ph..5308C; 2004astro.ph..5308A
We have detected longitudinal magnetic fields between 2 and 4 kG in
three (WD 0446-790, WD 1105-048, WD 2359-434) out of a sample of 12
normal DA white dwarfs by using optical spectropolarimetry done with the
VLT Antu 8 m telescope equipped with FORS1. With the exception of 40 Eri
B (4 kG) these are the first positive detections of magnetic fields in
white dwarfs below 30 kG. Although suspected, it was not clear whether
a significant fraction of white dwarfs contain magnetic fields at this
level. These fields may be explained as relics from magnetic fields in
the main-sequence progenitors considerably enhanced by magnetic flux
conservation during the shrinkage of the core. A detection rate of 25%
(3/12) may indicate now for the first time that a substantial fraction
of white dwarfs have a weak magnetic field. This result, if confirmed
by future observations, would form a cornerstone for our understanding
of the evolution of stellar magnetic fields. Based on observations
collected at the European Southern Observatory, Paranal, Chile, under
programme ID 70.D-0259.
Title: Do weak magnetic fields prevent hydrogen from accreting onto
metal-line white dwarf stars?
Authors: Friedrich, S.; Jordan, S.; Koester, D.
Bibcode: 2004A&A...424..665F
Altcode: 2004astro.ph..6229F
The widely accepted assumption is that metals detected in the spectra
of a few cool helium-rich white dwarfs cannot be of primordial origin
and therefore must be accreted from the interstellar medium. However,
the observed abundances of hydrogen are much too low to be compatible
with the high accretion rates inferred from metal accretion. Hydrogen
accretion is therefore suppressed compared to metal accretion. The
hypothesis most widely discussed as cause for this ``hydrogen
screening'' is the propeller mechanism: Metals are accreted in the
form of grains onto a slowly rotating, weakly magnetized white dwarf,
whereas ionized hydrogen is repelled at the Alfvén radius. We have
obtained circular polarization spectra of the helium-rich white
dwarfs GD 40 (WD0300-013) and
L745-46A (WD0738-172) - which
both show strong metal lines as well as hydrogen - in order to search
for signatures of a weak magnetic field. The magnetic field strengths
necessary for the propeller mechanism to work in these stars are at
least 144 000 G and 3000 G, respectively. Whereas L745-46A might have a
magnetic field of about -6900 G no magnetic field could be found with
an upper limit for the field strength of 4000 G (with 99% confidence)
for GD 40. Based on observations collected at the European Southern
Observatory, Paranal, Chile (ESO Programme 66.D-0541).
Title: HE0241-0155 - Evidence for a large scale homogeneous field
in a highly magnetic white dwarf
Authors: Reimers, D.; Jordan, S.; Christlieb, N.
Bibcode: 2004A&A...414.1105R
Altcode: 2003astro.ph.11076R
In the course of the Hamburg/ESO survey we have discovered a white dwarf
whose spectrum exhibits many similarities with the prototype of magnetic
white dwarfs Grw+70°8247. In particular several stationary
line components indicative for magnetic fields between about 150 and
400 MG are found in both objects. However, the features between 5000 and
5500 Å in the spectrum of HE0241-0155 cannot be explained by stationary
line components and demand a relatively homogeneous magnetic field with
clustering around 200 MG. For this reason a pure dipole model failed
to reproduce this spectral region. An offset-dipole configuration led
to some improvement in the fit but a good agreement was only possible
for a geometry - described by an expansion into spherical harmonics -
where most of the surface is covered with magnetic field strengths
strongly clustered around 200 MG. This may indicate the presence of a
large magnetic spot whose presence could be tested with time resolved
spectro-polarimetry. Based on observations collected at the
European Southern Observatory, La Silla, Chile.
Title: Evaluating Ground-based Proxies for Solar Irradiance variation
Authors: Jordan, S. D.; Garcia, M. A.
Bibcode: 2003SPD....34.1911J
Altcode: 2003BAAS...35..843J
In order to determine what ground-based proxies are best for evaluating
solar irradiance variation before the advent of space observations,
it is necessary to test these proxies against space observations. We
have tested sunspot number, total sunspot area, and sunspot umbral area
against the Nimbus-7 measurements of total solar irradiance variation
over the eleven year period 1980-1990. The umbral area yields the best
correlation and the total sunspot area yields the poorest. Reasons
for expecting the umbral area to yield the best correlation are given,
the statistical procedure followed to obtain the results is described,
and the value of determining the best proxy is discussed. The latter is
based upon the availability of an excellent database from the Greenwich
Observatory obtained over the period 1876-1976, which can be used to
estimate the total solar irradiance variation before sensitive space
observations were available. The ground-based observations used
were obtained at the Coimbra Solar Observatory. The analysis was done
at Goddard using these data and data from the Nimbus-7 satellite.
Title: The EUV helium spectrum in the quiet Sun: A by-product of
coronal emission?
Authors: Andretta, V.; Del Zanna, G.; Jordan, S. D.
Bibcode: 2003A&A...400..737A
Altcode:
In this paper we test one of the mechanisms proposed to explain the
intensities and other observed properties of the solar helium spectrum,
and in particular of its Extreme-Ultraviolet (EUV) resonance lines. The
so-called Photoionisation-Recombination (P-R) mechanism involves
photoionisation of helium atoms and ions by EUV coronal radiation,
followed by recombination cascades. We present calibrated measurements
of EUV flux obtained with the two CDS spectrometers on board SOHO,
in quiescent solar regions. We were able to obtain an essentially
complete estimate of the total photoionising flux in the wavelength
range below 504 Å (the photoionisation threshold for He I), as well as
simultaneous measurements with the same instruments of the intensities
of the strongest EUV He I and He Ii lines: \specline{He}i{584},
\specline{He}i{537}, and \specline{He}{ii}{304}. We find that there
are not enough EUV ionising photons to account for the observed helium
line intensities. More specifically, we conclude that He Ii intensities
cannot be explained by the P-R mechanism alone. Our results, however,
leave open the possibility that the He I spectrum could be formed by
the P-R mechanism, with the \specline{He}{ii}{304} line as a significant
photoionisating source.
Title: Magnetic white dwarfs in the SDSS
Authors: Gänsicke, B. T.; Euchner, F.; Jordan, S.
Bibcode: 2003ASIB..105..199G
Altcode: 2003whsw.conf..199G; 2003whdw.conf..199G
No abstract at ADS
Title: Transfer of Polarized Radiation - Practical Experience with
the Accelerated Lambda Iteration Method
Authors: Deetjen, J. L.; Dreizler, S.; Jordan, S.; Werner, K.
Bibcode: 2003ASPC..288..617D
Altcode: 2003sam..conf..617D
Neutron stars and some of the white dwarfs have magnetic fields. The
light emitted by these stars is polarized and can be characterized
by the four Stokes components I, Q, U, and V. Therefore the polarized
radiation transport equation differs significantly from the non-magnetic
case. It is a system of linear differential equations coupled in
I, Q, U, and V with depth dependent opacities and magneto-optical
parameters. The most potential method, the accelerated lambda iteration,
is presented in detail and practical experiences calculating neutron
star atmospheres are reported.
Title: Do Magnetic Fields Prevent Hydrogen from Accreting on to Cool
Metal-line White Dwarfs?
Authors: Friedrich, S.; Jordan, S.; Koester, D.
Bibcode: 2003ASIB..105..203F
Altcode: 2003whsw.conf..203F; 2003whdw.conf..203F
No abstract at ADS
Title: Progress in modeling magnetic white dwarfs
Authors: Jordan, S.
Bibcode: 2003ASIB..105..175J
Altcode: 2003whsw.conf..175J; 2003astro.ph..2058J; 2003whdw.conf..175J
First satisfactory fits to the flux spectrum and circular polarization
of the DAP Grw +70 8247 are presented, as well as a first model of
the DBP GD 229 with consistent helium line data.
Title: Four Numerical Approaches for Solving the Radiative Transfer
Equation in Magnetized White-Dwarf Atmospheres
Authors: Jordan, S.; Schmidt, H.
Bibcode: 2003ASPC..288..625J
Altcode: 2003sam..conf..625J; 2003astro.ph..2047J
The observed spectrum and wavelength dependent polarization of magnetic
white dwarfs can be analyzed by simulating the transport of polarized
radiation through a magnetized stellar atmosphere. The four
coupled radiative transport equations for the Stokes parameters I,
Q, V, and U, can be solved by different numerical approaches. In this
talk the numerical results and efficiencies of four different methods
are discussed: (a) the method of Wickramasinghe & Martin which
assumes that the source function is linear in the optical depth and
that between two successive depth points the Stokes parameters can
be described by exponential functions; (b) accelerated Λ iterations
(see also the talk by J. Deetjen) (c) an approximation for large
Faraday rotation, and (d) the matrix exponential solutions.
Title: Zeeman tomography of magnetic white dwarfs: General method
and application to EF Eridani
Authors: Euchner, F.; Beuermann, K.; Reinsch, K.; Jordan, S.; Hessman,
F. V.; Gänsicke, B. T.
Bibcode: 2003ASIB..105..195E
Altcode: 2003astro.ph..3336E; 2003whdw.conf..195E; 2003whsw.conf..195E
We have developed a new method to derive the magnetic field distribution
on the surfaces of rotating magnetic white dwarfs from phase-resolved
flux and circular polarization spectra. An optimization code based
on an evolutionary strategy is used to fit synthetic Zeeman spectra
for a variety of model geometries described in the framework of a
truncated multipole expansion. We demonstrate that the code allows
the reconstruction of relatively complex fields using noise-added
synthetic input spectra. As a first application, we analyze flux and
circular polarization spectra of the polar EF Eri in a low state of
accretion taken with FORS1 at the ESO VLT.
Title: Magnetic white dwarfs in the Early Data Release of the Sloan
Digital Sky Survey
Authors: Gänsicke, B. T.; Euchner, F.; Jordan, S.
Bibcode: 2002A&A...394..957G
Altcode: 2002astro.ph..8454G
We have identified 7 new magnetic DA white dwarfs in the Early Data
Release of the Sloan Digital Sky Survey. Our selection strategy
has also recovered all the previously known magnetic white dwarfs
contained in the SDSS EDR, KUV 03292+0035 and HE 0330-0002. Analysing
the SDSS fibre spectroscopy of the magnetic DA white dwarfs with our
state-of-the-art model spectra, we find dipole field strengths 1.5
MG<=Bd<= 63 MG and effective temperatures 8500 <=
Teff <= 39 000 K. As a conservative estimate, we expect
that the complete SDSS will increase the number of known magnetic
white dwarfs by a factor 3.
Title: Zeeman tomography of magnetic white dwarfs. I. Reconstruction
of the field geometry from synthetic spectra
Authors: Euchner, F.; Jordan, S.; Beuermann, K.; Gänsicke, B. T.;
Hessman, F. V.
Bibcode: 2002A&A...390..633E
Altcode: 2002astro.ph..5294E
We have computed optical Zeeman spectra of magnetic white dwarfs
for field strengths between 10 and 200 MG and effective temperatures
between 8000 and 40 000 K. They form a database containing 20 628 sets
of flux and circular polarization spectra. A least-squares optimization
code based on an evolutionary strategy can recover relatively complex
magnetic field topologies from phase-resolved synthetic Zeeman spectra
of rotating magnetic white dwarfs. We consider dipole and quadrupole
components which are non-aligned and shifted off-centre. The model
geometries include stars with a single high-field spot and with two
spots separated by ~ 90°. The accuracy of the recovered field structure
increases with the signal-to-noise ratio of the input spectra and is
significantly improved if circular polarization spectra are included
in addition to flux spectra. We discuss the strategies proposed so
far to unravel the field geometries of magnetic white dwarfs.
Title: Comparing Sunspot Area and Sunspot Number as Proxies for
Long-term Solar Irradiance Variation
Authors: Jordan, S. D.; Garcia, A. G.
Bibcode: 2002AAS...200.5704J
Altcode: 2002BAAS...34..737J
Because relevant observations from space began only in 1979 with
Nimbus-7, it is impossible to correlate direct measurements of small
changes in solar irradiance with terrestrial temperature over a number
of solar cycles. Yet there is recent evidence that some feature of
solar change over a cycle may have a larger influence on climate than
would result from merely introducing the additional amount of heat
delivered to Earth's atmosphere at solar minimum. It would be useful to
check this possiblity over several solar cycles. To do this, we would
need a sufficiently reliable proxy for irrradiance change that at least
survives a test against the space observations. Sunspot area is a fairly
straightforward parameter to measure, and is associated with the extent
of magnetic activity known to correlate strongly with solar irradiance
change. We have tested the use of sunspot area as a long-term proxy
for solar irradiance change, using observations made at the Coimbra
Solar Observatory, from which we obtain both statistically weighted
sunspot numbers and sunspot areas over the period 1980-1992. These are
both correlated with solar irradiance values measured from Nimbus-7
spacecraft over the same time period, to see if sunspot area offers
affords a strong positive correlation and also a distinct advantage
over sunspot number as a useful proxy that can then be compared with
terrestrial temperature records. Preliminary results yield a positive
correlation of 0.71 for sunspot area, but further tests are being
conducted and will be reported.
Title: On the circularly polarized optical emission from AE Aquarii
Authors: Ikhsanov, N. R.; Jordan, S.; Beskrovnaya, N. G.
Bibcode: 2002A&A...385..152I
Altcode: 2002astro.ph..1366I
The reported nightly mean value of the circular polarization of
optical emission observed from the close binary system AE Aqr is 0.06%
33Rmms m 0.01%. We discuss the possibility that
the observed polarized radiation is emitted mainly by the white dwarf
or its vicinity. We demonstrate that this hypothesis is rather unlikely
since the contribution of the white dwarf to the optical radiation of
the system is too small. This indicates that the polarimetric data
on AE Aqr cannot be used for the evaluation of the surface magnetic
field strength of the white dwarf in this system.
Title: An evaluation of solar proxies for irradiance variation
Authors: Jordan, Stuart; Garcia, Adriana
Bibcode: 2002ESASP.477..225J
Altcode: 2002scsw.conf..225J
The problem of assessing the effects of solar irradiance variations
on Earth's climate has become of increasing importance as evidence
accumulates for global warming. Reliable observations of irradiance
variation from space are available only for the past two solar
cycles. Proxies must be used to estimate the irradiance variation before
that time. We report on preliminary results of testing sunspot area
as a relatively easily observed proxy against spatial observations of
the irradiance variation. We discuss these early results and outline
our plans for the remainder of the study.
Title: Search for variations in circular-polarization spectra of
the magnetic white dwarf LP 790-29
Authors: Jordan, S.; Friedrich, S.
Bibcode: 2002A&A...383..519J
Altcode: 2002astro.ph..1122J
We present highly time resolved circular-polarization and flux spectra
of the magnetic white dwarf LP 790-29 taken with the VLT UT1 in order
to test the hypothesis that LP 790-29 is a fast rotator with a period
of the order of seconds to minutes. Due to low time resolution of
former observations this might have been overlooked - leading to
the conclusion that LP 790-29 has a rotational period of over 100
years. The optical spectrum exhibits one prominent absorption feature
with minima at about 4500, 4950, and 5350 Å, which are most likely
C_2 Swan-bands shifted by about 180 Å in a magnetic field between 50
MG and 200 MG. At the position of the absorption structures the degree
of circular polarization varies between -1% and +1%, whereas it amounts
to +8 to +10% in the blue and red continuum. With this very high degree
of polarization LP 790-29 is very well suited to a search for short time
variations, since a variation of several percent in the polarization can
be expected for a magnetic field oblique to the rotational axis. From
our analysis we conclude that variations on time scales from 50
to 2500 s must have amplitudes ≈0.7% in the continuum and ≈2%
in the strongest absorption feature at 4950 Å. While no short-term
variations could be found a careful comparison of our polarization
data of LP 790-29 with those in the literatures indicates significant
variations on time scales of decades with a possible period of about
24-28 years. Based on observations collected at the European Southern
Observatory, Paranal, Chile (ESO Programme 65.H-0293).
Title: Some Impacts of Solar Irradiance Variation on Terrestrial
Climate
Authors: Jordan, S. D.
Bibcode: 2001AAS...199.3601J
Altcode: 2001BAAS...33.1359J
As chairman of the Special Session addressing the above topic, a brief
overview of the problem will be offered, after which 20-minute talks
will be given on the determination of solar irradiance variations from
space observations (Dr. Judit Pap) and from ground-based measurements
of solar magnetic fields (Dr. Harrison Jones). The chairman will
then introduce four panel members representing different areas
of expertise bearing on the topic. Each panel member will offer a
brief 5-minute summary of his views. Panel members are Chick Keller,
Los Alamos National Laboratory; Drew Shindell, Goddard Institute for
Space Science, Columbia University; Michael Schlesinger, University of
Illinois; Sabatino Sofia, Yale University. General Circulation Models
of the terrestrial atmosphere, the possible impact on this atmosphere
of large percentage changes in the solar EUV over a solar cycle,
and the role of strong magnetic fields in the solar convection zone
on irradiance variation will all be considered in brief summaries. The
chairman will conclude the session by facilitating a discussion between
the audience, the main speakers, and the panel members.
Title: Stationary components of He I in strong magnetic fields -
a tool to identify magnetic DB white dwarfs
Authors: Jordan, S.; Schmelcher, P.; Becken, W.
Bibcode: 2001A&A...376..614J
Altcode: 2001astro.ph..6560J
In only three of the 61 known magnetic white dwarfs helium has been
identified unambiguously while about 20% of all non-magnetic stars
of this class are known to contain He I or He II. One reason for
this discrepancy is that the identification of peculiar objects as
magnetic white dwarfs is based either on the presence of hydrogen line
components in strong magnetic fields - for which atomic data exist
since 1984 - or the polarization of the corresponding radiation which
has not been measured for many objects. Until recently, data for He I
data were available only for magnetic fields below 20 MG. This changed
with the publication of extensive data by the group in Heidelberg. The
corresponding calculations have now been completed for the energetically
lowest five states of singlet and triplet symmetry for the subspaces
with |m| <= 3; selected calculations have been performed for even
higher excitations. In strongly magnetized white dwarfs only line
components are visible whose wavelengths vary slowly with respect
to the magnetic field, particularly stationary components which have
a wavelength minimum or maximum in the range of the magnetic fields
strengths on the stellar surface. In view of the many ongoing surveys
finding white dwarfs we want to provide the astronomical community
with a tool to identify helium in white dwarfs for fields up to 5.3
GG. To this end we present all calculated helium line components
whose wavelengths in the UV, optical, and near IR vary slowly enough
with respect to the field strength to produce visible absorption
features. We also list all stationary line components in this spectral
range. Finally, we find series of minima and maxima which occur as
a result of series of extremal transitions to increasingly higher
excitations. We estimated the limits for 8 series which can possibly
give rise to additional absorption in white dwarf spectra; one strong
absorption feature in GD229 which is yet unexplained by stationary
components is very close to two estimated series limits.
Title: Search for indications of fast rotation in the linear
polarization of the magnetic white dwarf Grw+70o8247
Authors: Friedrich, S.; Jordan, S.
Bibcode: 2001A&A...367..577F
Altcode:
Grw+70o8247 belongs to a small group of magnetic
white dwarfs which despite repeated observations did not show any
changes in their polarization over decades. The inferred rotation
periods are of the order of hundred years which is not easy to
understand if angular momentum is conserved during stellar evolution. An
alternative possibility, which was to our knowledge never investigated,
might be fast rotation with a period between some minutes and a couple
of seconds. Assuming a mass of 1 M_sun and a radius of 1/100 R_sun
the shortest possible period is about 10 s. In order to test this
hypothesis the linear polarization of {Grw+70o8247} was
measured at the 2.2 m telescope at the Calar Alto Observatory, Spain,
with a time resolution of 3 s by trailing the linear polarized image
of Grw+70o8247 over the CCD chip. The linear polarization
was searched for periodicities in the range between 10 s and 4000
s. Investigations with synthetic polarized data using the same
window function and an assumed sinusoidal variation showed that
variations with amplitudes of 40% relative to the amount of average
linear polarization should be detectable. However, no periodicities
at this or higher levels of significance were found. This would be
in accordance with a recent report on slow rotation of GD
229 and G 240-72, but fast variations
with lower amplitudes could not be ruled out. Based on observations
collected at the German-Spanish Astronomical Center (DSAZ), Calar Alto,
operated by the Max-Planck-Institut für Astronomie Heidelberg jointly
with the Spanish National Commission for Astronomy.
Title: Search for Weak Magnetic Fields in DBZ and DBAZ White Dwarfs
Authors: Friedrich, S.; Jordan, S.; Koester, D.
Bibcode: 2001AGM....18.P114F
Altcode: 2001AGAb...18Q.192F
It is widely accepted that metals detected in the spectra of a
few cool white dwarfs cannot be of primordial origin and therefore
must be accreted from the interstellar medium. However the observed
abundances of hydrogen in the atmospheres of these stars are much too
low to be compatible with the high accretion rates inferred from metal
accretion if solar abundances are assumed. It was therefore proposed
that metals are accreted in the form of grains onto a slowly rotating,
weakly magnetized white dwarf, whereas ionized hydrogen is repelled
at the Alfven radius. In order to test this hypothesis we obtained
circular polarization spectra of two metal line white dwarfs (GD40
and L745-46A) with the VLT-UT1 and FORS1 to search for such magnetic
fields. Within the errors (±0.1% and ±0.3% for L745-46A and GD40,
respectively) we could not find signatures of a magnetic field in
the spectra of any of the two stars. If we exclude the possibility,
that we are looking on the magnetic equator of a pure magnetic dipole,
in which case the components of the magnetic field along the line of
sight completely cancel and no circular polarization can be detected,
we conclude, that the field strength of the magnetic field on both
stars must be well below the 105 Gauss required by theory. We
could confirm an Hα line in the flux spectrum of GD40, which was found
by Greenstein & Liebert (ApJ 360, 662) and determine the hydrogen
abundance in the stellar atmosphere which is a factor of 100 to 1000
below the value expected from accretion with solar abundances.
Title: New Results on Magnetic White Dwarfs
Authors: Jordan, S.
Bibcode: 2001AGM....18S0917J
Altcode:
A small fraction (3-4%) of all white dwarfs are found to have strong
magnetic fields, and 15 of these 61 objects have fields in excess
of 100 MG making them comparable to the typical field strengths
found in millisecond pulsars. Besides the astrophysical aspects
(field strength and geometry, rotation, masses, chemical composition,
origin of magnetic fields) these objects are of considerable interest
for studies of atoms in strong magnetic fields. In only three magnetic
white dwarfs helium has been identified unambiguously while about 20%
of all non-magnetic stars of this class are known to contain He I
or He II. Until recently, data for He I data were available only for
magnetic fields below 20 MG. Now calculations for all relevant field
strenghts have been completed for the energetically lowest five states
of singlet and triplet symmetry for the subspaces with |m| <= 3
(Jordan, Schmelcher, Becken, 2001, A&A, in press). In this talk
some new results particularly on helium rich magnetic white dwarfs
will be presented.
Title: The Kepler Mission: A Search for Terrestrial Planets
Authors: Koch, D.; Borucki, W.; Webster, L.; Jenkins, J.; Dunham,
E.; Jordan, S.; Kepler Team
Bibcode: 2001AGM....18S0406K
Altcode:
The Kepler Mission is a search for terrestrial planets performed by
monitoring a large ensemble of stars for the periodic transits of
planets. The mission consists of a 95-cm aperture photometer with
105 square deg field of view that monitors 100,000 dwarf stars for
four years. The mission is unique in its ability to detect Earth-size
planets in the habitable zone of other stars in the extended solar
neighborhood. An Earth-size transit of a solar-like star causes a change
in brightness of about 100 ppm. Laboratory testing has demonstrated
that a total system noise level of 20 ppm is readily achievable on
the timescale of transits. Earth-like transits have been created and
reliably measured in an end-to-end system test that has all know sources
of noise including spacecraft jitter. To detect Earth-size planets, the
photometer must be spaceborne; this also eliminates the day-night and
seasonal cycle interruptions of ground-based observing. The photometer
stares at a single field of stars for four years with an option to
continue for two more years. The extension allows for detection of
four transits of planets in Mars-like orbits and detection of planets
even smaller than Earth especially for short period orbits, since the
signal to noise improves as the square root of the number of transits
observed. In addition to detection of planets, Kepler data are also
useful for understanding the
Title: HST Observations of the DAB White Dwarf HS 0209+0832
Authors: Wolff, B.; Jordan, S.; Koester, D.
Bibcode: 2001ASPC..226..139W
Altcode: 2001ewwd.work..139W
No abstract at ADS
Title: Magnetic White Dwarfs
Authors: Jordan, S.
Bibcode: 2001ASPC..226..269J
Altcode: 2001ewwd.work..269J
No abstract at ADS
Title: Search for fast rotation in Grw + 70°8247
Authors: Friedrich, S.; Jordan, S.
Bibcode: 2001ASPC..226..279F
Altcode: 2001ewwd.work..279F
No abstract at ADS
Title: Numerical Simulation of Stellar Convection: Comparison with
Mixing-length Theory
Authors: Steffen, M.; Jordan, S.
Bibcode: 2000eaa..bookE5198S
Altcode:
The energy released by nuclear fusion in the STELLAR INTERIOR
is carried to the surface by two different transport mechanisms,
radiation and convection. In the presence of a temperature gradient,
there is always a net radiative energy flux since more photons travel
from hot to cool regions than in the other direction. If the temperature
gradient exceeds a certain t...
Title: The nature of the DAB white dwarf HS 0209+0832
Authors: Wolff, B.; Jordan, S.; Koester, D.; Reimers, D.
Bibcode: 2000A&A...361..629W
Altcode:
The DAB white dwarf HS 0209+0832 is one of the
few white dwarfs with detected helium in the DB gap between 28
000 and 45 000 K. We have obtained ultraviolet and optical spectra
with the Hubble Space Telescope (HST). The analysis results in an
effective temperature of about 35 000 K and a helium abundance of about
1%. The presence of C IV at 1548 Å, which was earlier detected by the
International Ultraviolet Explorer (IUE), is confirmed. Additionally,
we could identify more than 140 photospheric and 12 interstellar metal
lines. For the first time we have found aluminum, calcium, titanium,
nickel, and zinc, which cannot be supported by radiative levitation at
such a low effective temperature. With stratified model atmospheres
we tested, whether HS 0209+0832 has a very thin layer of hydrogen
(~ 10-16 Msun) on top of the helium envelope
so that it is not thick enough to hide all the helium as is usually
assumed to explain the DB gap. From the detailed shape of the He II
1640 Å line we could exclude such a model and conclude that diffusion
equilibrium has not yet been reached; all observations are compatible
with almost homogeneously mixed atmospheres, as would also be expected
from the presence of metal lines. The most probable explanation is that
HS 0209+0832 is still accreting matter from an interstellar cloud and
that helium and metals would sink downwards, if no longer supplied from
the surrounding medium. The finding by Heber et al. (\cite{Heber}) that
the He I line at 4471 Å has been weaker by a factor of two or three
for several months would fit into this scenario, if we assume that HS
0209+0832 travels through an inhomogeneous medium. Based on observations
made with the NASA/ESA Hubble Space Telescope, obtained at the Space
Telescope Science Institute, which is operated by the Association of
Universities for Research in Astronomy, Inc., under NASA contract NAS
5-26555. These observations are associated with proposal ID 7473.
Title: The Role of Velocity Redistribution in Enhancing the Intensity
of the HE II 304 Å Line in the Quiet-Sun Spectrum
Authors: Andretta, Vincenzo; Jordan, Stuart D.; Brosius, Jeffrey W.;
Davila, Joseph M.; Thomas, Roger J.; Behring, William E.; Thompson,
William T.; Garcia, Adriana
Bibcode: 2000ApJ...535..438A
Altcode:
We present observational evidence of the effect of small-scale
(``microturbulent'') velocities in enhancing the intensity of the
He II λ304 line with respect to other transition region emission
lines, a process we call ``velocity redistribution,''. We first show
results from the 1991 and 1993 flights of SERTS (Solar EUV Rocket
Telescope and Spectrograph). The spectral resolution of the SERTS
instrument was sufficient to infer that, at the spatial resolution
of 5", the line profile is nearly Gaussian both in the quiet Sun and
in active regions. We were then able to determine, for the quiet Sun,
a lower limit for the amplitude of nonthermal motions in the region of
formation of the 304 Å line of the order of 10 km s-1. We
estimated that, in the presence of the steep temperature gradients
of the solar transition region (TR), velocities of this magnitude
can significantly enhance the intensity of that line, thus at least
helping to bridge the gap between calculated and observed values. We
also estimated the functional dependence of such an enhancement on
the relevant parameters (nonthermal velocities, temperature gradient,
and pressure). We then present results from a coordinated campaign,
using SOHO/CDS and Hα spectroheliograms from Coimbra Observatory,
aimed at determining the relationship between regions of enhanced
helium emission and chromospheric velocity fields and transition region
emission in the quiescent atmosphere. Using these data, we examined
the behavior of the He II λ304 line in the quiet-Sun supergranular
network and compared it with other TR lines, in particular with O III
λ600. We also examined the association of 304 Å emission with the
so-called coarse dark mottle, chromospheric structures seen in Hα
red-wing images and associated with spicules. We found that all these
observations are consistent with the velocity redistribution picture.
Title: HST Observations of the DAB White Dwarf HS 0209+0832
Authors: Wolff, B.; Jordan, S.; Koester, D.
Bibcode: 2000AGM....17..P36W
Altcode: 2000AGAb...17Q..67W
The DAB white dwarf HS 0209+0832 is one of the few white dwarfs with
detected helium in the DB gap between 28 000 and 45 000 K. We have
obtained ultraviolet and optical spectra with the Hubble Space Telescope
(HST). The analysis results in an effective temperature of about 35 000
K and a helium abundance of about 1%. The presence of C IV at 1548 Å,
which was earlier detected by the International Ultraviolet Explorer
(IUE), is confirmed. Additionally, we could identify more than 140
photospheric and 12 interstellar metal lines. For the first time
we have found aluminum, calcium, titanium, nickel, and zinc, which
cannot be supported by radiative levitation at such a low effective
temperature. With stratified model atmospheres we tested, whether
HS 0209+0832 has a very thin layer of hydrogen (≈ 10-16
Msolar) on top of the helium envelope so that it is not thick
enough to hide all the helium as is usually assumed to explain the DB
gap. From the detailed shape of the He II 1640 Å line we could exclude
such a model and conclude that diffusion equilibrium has not yet been
reached; all observations are compatible with almost homogeneously
mixed atmospheres, as would also be expected from the presence of
metal lines. The most probable explanation is that HS 0209+0832 is
still accreting matter from an interstellar cloud and that helium and
metals would sink downwards, if no longer supplied from the surrounding
medium. The finding by Heber et al. that the He I line at 4471 Å has
been weaker by a factor of two or three for several months would fit
into this scenario, if we assume that HS 0209+0832 travels through an
inhomogeneous medium.
Title: Does Velocity Redistribution Really Enhance the He 304Å Line
to Observed Intensities?
Authors: Jordan, S.; Andretta, V.; Garcia, A.; Brosius, J.; Behring, W.
Bibcode: 1999ESASP.448..303J
Altcode: 1999mfsp.conf..303J; 1999ESPM....9..303J
No abstract at ADS
Title: A Direct Comparison Between EUV Coronal Flux And He Resonance
Line Photon Flux From SOHO/CDS Data
Authors: Andretta, V.; Landi, Enrico; Del Zanna, Giulio; Jordan,
Stuart D.
Bibcode: 1999ESASP.446..123A
Altcode: 1999soho....8..123A
In the wealth of EUV spectroscopic and imaging data gathered by the
SOHO and TRACE missions, a prominent role is played by the helium
resonance emission. For example, He I lines are among the most intense
features in CDS/NIS spectra, while the EIT 304 waveband (dominated by
He II emission) is routinely employed to map the structure of the solar
chromosphere and transition region. However, no 'standard' model has
emerged so far that is able to interpret observed He spectra/images
to a satisfactory degree of self-consistency. Recent research on
the problem of the formation of the solar helium spectrum tends to
rule out a dominant role of coronal radiation in exciting He resonance
lines. However, while evidence for this result is strong, it is based on
indirect tests. Here we present a more direct assessment of this issue
by directly measuring the photon photoionizing EUV flux measured with
CDS/GIS-NIS1. This measure can be directly compared with the observed
flux in the main He I and He II resonance lines observed with CDS/NIS2.
Title: The Role of Velocity Redistribution in Enhancing the Intensity
of the He II 304 A Line in the Quiet Sun Spectrum
Authors: Andretta, Vincenzo; Jordan, Stuart D.; Brosius, Jeffrey W.;
Davila, Joseph M.; Thomas, Roger J.; Behring, William E.; Thompson,
William T.; Garcia, Adriana
Bibcode: 1999STIN...9909151A
Altcode:
We present observational evidence of the effect of small scale
("microturbulent") velocities in enhancing the intensity of the He
II lambda304 line with respect to other transition region emission
lines, a process we call "velocity redistribution". We first show
results from the 1991 and 1993 flights of SERTS (Solar EUV Rocket
Telescope and Spectrograph). The spectral resolution of the SERTS
instrument was sufficient to infer that, at the spatial resolution
of 5", the line profile is nearly gaussian both in the quiet Sun and
in active regions. We were then able to determine, for the quiet Sun,
a lower limit for the amplitude of non-thermal motions in the region
of formation of the 304 A line of the order of 10 km/s. We estimated
that, in the presence of the steep temperature gradients of the solar
Transition Region (TR), velocities of this magnitude can significantly
enhance the intensity of that line, thus at least helping to bridge
the gap between calculated and observed values. We also estimated the
functional dependence of such an enhancement on the relevant parameters
(non-thermal velocities, temperature gradient, and pressure). We then
present results from a coordinated campaign, using SOHO/CDS and H-alpha
spectroheliograms from Coimbra Observatory, aimed at determining
the relationship between regions of enhanced helium emission and
chromospheric velocity fields and transition region emission in the
quiescent atmosphere. Using these data, we examined the behavior of
the He II lambda304 line in the quiet Sun supergranular network and
compared it with other TR lines, in particular with O III lambda600. We
also examined the association of 304 A emission with the so-called
"coarse dark mottle", chromospheric structures seen in H-alpha red
wing images and associated with spicules. We found that all these
observations are consistent with the velocity redistribution picture.
Title: Velocity Redistribution as a He II 304 Intensity Enhancement
Mechanism
Authors: Jordan, S. D.; Andretta, V.; Brosius, J. W.; Behring, W. E.;
Garcia, A.
Bibcode: 1999AAS...194.9310J
Altcode: 1999BAAS...31..990J
Both Skylab and SOHO observations show that the total intensity in
the He II 304 Angstroms line exceeds that predicted by standard NLTE
models by at least a factor of 5. However, the NLTE models do not
include the effect of flows. Carole Jordan showed that a 'velocity
redistribution' of the He II ions in the presence of a sharp temperature
gradient could provide the required enhancement. In earlier studies,
we have reported evidence from the Goddard SERTS sounding rocket for
small-scale nonthermal velocities large enough to enhance the emission
by the required amount if the temperature gradient is large enough
(as given by current transition region models). Here, we assess the
correlation of regions of strong Sun-center quiet-Sun 304 emission
observed with the CDS instrument on SOHO and the dark coarse mottles
observed in the red wing of H-alpha observed at the Coimbra Solar
Observatory. The significant positive correlation supports the picture
of greater velocity mixing in the quiet-Sun regions producing the
highest line intensity. Support for this research is provided by NASA
grant 682-344-17-38 and the Coimbra Solar Observatory.
Title: The SERTS-97 rocket experiment to study activity on the Sun:
flight 36.167-GS on 1997 November 18.
Authors: Swartz, Marvin; Condor, Charles E.; Davila, Joseph M.; Haas,
J. Patrick; Jordan, Stuart D.; Linard, David L.; Miko, Joseph J.;
Nash, I. Carol; Novello, Joseph; Payne, Leslie J.; Plummer, Thomas
B.; Thomas, Roger J.; White, Larry A.; Brosius, Jeffrey W.; Thompson,
William T.
Bibcode: 1999sret.book.....S
Altcode:
This paper describes mainly the 1997 version of the Solar EUV Rocket
Telescope and Spectrograph (SERTS-97), a scientific experiment that
operated on NASA's suborbital rocket flight 36.167-GS. Its function
was to study activity on the Sun and to provide a cross calibration
for the CDS instrument on the SOHO satellite.
Title: Quasi-molecular satellites of Lyman β observed with ORFEUS
Authors: Allard, N.; Koester, D.; Sperhake, U.; Jordan, S.; Finley, D.
Bibcode: 1999ASPC..169..461A
Altcode: 1999ewwd.conf..461A
No abstract at ADS
Title: Helium in magnetic white dwarfs
Authors: Jordan, S.
Bibcode: 1999ASPC..169..228J
Altcode: 1999ewwd.conf..228J
No abstract at ADS
Title: Phase-resolved Far-Ultraviolet Hubble Space Telescope
Spectroscopy of the Peculiar Magnetic White Dwarf RE J0317-853
Authors: Burleigh, M. R.; Jordan, S.; Schweizer, W.
Bibcode: 1999ApJ...510L..37B
Altcode: 1998astro.ph.10109B
We present phase-resolved, far-UV Hubble Space Telescope Faint Object
Spectrograph spectra of the rapidly rotating, highly magnetic white
dwarf RE J0317-853. Using these data, we construct a new model for
the magnetic field morphology across the stellar surface. From an
expansion into spherical harmonics, we find that the range of magnetic
field strengths present is 180-800 MG. For the first time, we could
identify an absorption feature present at certain phases at ~1160
Å as a ``forbidden'' 1s0-->2s0 component,
because of the combined presence of an electric and magnetic field.
Title: The stellar content of the Hamburg Quasar Survey
Authors: Homeier, D.; Koester, D.; Jordan, S.; Hagen, H. -J.; Engels,
S.; Heber, U.; Dreizler, S.
Bibcode: 1999ASPC..169...37H
Altcode: 1999ewwd.conf...37H
No abstract at ADS
Title: Does Velocity Redistribution Really Enhance the HE 304 A Line
to Observed Intensities?
Authors: Jordan, Stuart; Andretta, Vincenzo; Garcia, Adriana; Brosius,
Jeffrey; Behring, William
Bibcode: 1999STIN...9909149J
Altcode:
Previous work by this group has demonstrated that small-scale
nonthermal velocities probably play a significant role in enhancing the
intensity of the He II 304 A line above values predicted by the static
atmosphere NLTE theories, and more in conformity with Skylab and SOHO
observations. This presentation briefly summarizes the evidence for this
conclusion, emphasizing SOHO and correlated groundbased observations,
of which examples are presented. However, in contrast to the previous
studies, the tact taken here is more critical, asking the question
"Can velocity redistribution fully explain the observations of the 304 A
line, and what counter-indications and problems remain?" The conclusion
reached is that, while velocity redistribution plays a significant
role in the intensity enhancement, it may not be the whole story. Some
other mechanism, associated with velocity filtration, may be at work.
Title: The record breaking magnetic white dwarf RE J0317-853
Authors: Jordan, S.; Burleigh, M. R.
Bibcode: 1999ASPC..169..235J
Altcode: 1999ewwd.conf..235J
No abstract at ADS
Title: An analysis of DA white dwarfs from the Hamburg Quasar Survey
Authors: Homeier, D.; Koester, D.; Hagen, H. -J.; Jordan, S.; Heber,
U.; Engels, D.; Reimers, D.; Dreizler, S.
Bibcode: 1998A&A...338..563H
Altcode:
Follow-up spectroscopy of several hundred hot stars detected by
the Hamburg Quasar Survey (HQS) has been carried out between 1989
and 1996. We present the analysis of 80 DA white dwarfs using model
atmospheres and theoretical cooling tracks to derive the atmospheric
parameters T_eff and log g, masses and absolute magnitudes. The HQS
turned out to be sensitive to the detection of hydrogen-rich white
dwarfs in a wide temperature range, from 10 000 K upwards. Star counts
within four HQS fields for magnitudes B<= 16fm 4 exceed those from
the Palomar Green survey by about 50%. The more recent observation
campaigns emphasized the detection of very hot degenerates, yielding
a large fraction of DA stars with T_eff > 50 000 K compared to
other surveys. The mean mass of our DA sample is M=0.61{M}_{\odot},
with three massive DA stars exceeding 1{M}_{\odot} and three DA
stars with masses significantly below the assummed lower mass limit
for single white dwarf evolution of 0.45{M}_{\odot}. Among the cool
DA stars, thirteen are potential ZZ Ceti candidates because their
effective temperatures lie close to the instability strip. Based
on observations collected at the German-Spanish Astronomical Center
(DSAZ), Calar Alto, operated by the Max-Plank-Institut für Astronomie
Heidelberg jointly with the Spanish National Commission for Astronomy;
with the International Ultraviolet Explorer satellite (IUE) collected
at Villafranca, Spain, and with the ROSAT X-ray telescope.
Title: Four magnetic DB white dwarfs discovered by the Hamburg/ESO
survey
Authors: Reimers, D.; Jordan, S.; Beckmann, V.; Christlieb, N.;
Wisotzki, L.
Bibcode: 1998A&A...337L..13R
Altcode: 1998astro.ph..7135R
We report on seven peculiar faint blue stars found in the course of
the Hamburg/ESO survey (HES) which appear to be magnetic white dwarfs
(WDs) with non-hydrogen spectra. We show in particular that four of
them (HE 0338-3853, HE 0107-0158,
HE 0026-2150, and HE 0003-5701)
have He I lines split by magnetic fields of roughly 20 MG, since the
pi components of He I 5876 {Angstroms} and He I 4929 {Angstroms}
can be identified unambiguously in their spectra, and the sigma
(+) , sigma (-) components can be identified in the spectra of two
of these stars (HE 0338-3853 and HE
0003-5701). Besides GD 229, these are
the first magnetic DB white dwarfs discovered so far. In addition,
three further WDs with broad, unidentifiable features have been found:
HE 1043-0502, HE 0236-2656,
and HE 0330-0002. We argue that in all three of
these stars H I can not be responsible for the broad features, and He I
most probably not for the features in HE 0236-2656
and HE 0330-0002, while it still remains possible
that the broad features of HE 1043-0502 are due
to He I. Based on observations at the European Southern Observatory,
La Silla, Chile
Title: Quasi-molecular satellites of Lyman beta in ORFEUS observations
of DA white dwarfs
Authors: Koester, D.; Sperhake, U.; Allard, N. F.; Finley, D. S.;
Jordan, S.
Bibcode: 1998A&A...336..276K
Altcode:
Quasi-molecular satellite features of Ly beta were first observed
in a HUT spectrum of the DA white dwarf Wolf 1346 and interpreted
by Koester et al. (1996). In this paper we study the dependence of
these features on temperature and surface gravity in 4 additional DA
observed with ORFEUS-SPAS II in 1996. For the interpretation we use
theoretical atmosphere models which incorporate new profiles for Ly
beta . These have been calculated by Allard et al. (1998a) including
the variation of the transition probability with distance between
emitter and perturber. The new calculations for the general line shape,
satellite positions and strengths are in very good agreement with
the observations.
Title: Evidence for helium in the magnetic white dwarf GD 229
Authors: Jordan, S.; Schmelcher, P.; Becken, W.; Schweizer, W.
Bibcode: 1998A&A...336L..33J
Altcode: 1998astro.ph..6338J
The nature of the strong absorption features in the white dwarf GD
229 has been a real mystery ever since it was found to be magnetic
in 1974. All attempts to explain the spectrum by line components of
hydrogen failed. With the first sets of newly calculated line data for
He I in a strong magnetic field we could identify most of the absorption
structures in the spectrum with stationary line components in a range
of magnetic fields between 300 and 700 MG. This is much lower than
previously speculated and is comparable to the highest fields found
in hydrogen rich magnetic white dwarfs. The reason for the large
number of spectral features in GD 229 is the extreme accumulation of
stationary components of transitions in He I in a narrow interval of
field strengths.
Title: Using Strong Solar Coronal Emission Lines as Coronal Flux
Proxies
Authors: Falconer, David A.; Jordan, Stuart D.; Brosius, Jeffrey W.;
Davila, Joseph M.; Thomas, Roger J.; Andreatta, Vicenzo; Hara, Hirohisa
Bibcode: 1998SoPh..180..179F
Altcode:
We investigate the possibility that strong EUV lines observed with the
Goddard Solar EUV Rocket Telescope and Spectrograph (SERTS) provide
good proxies for estimating the total coronal flux over shorter
wavelength ranges. We use coordinated SERTS and Yohkoh observations
to obtain both polynomial and power-law fits relating the broad-band
soft X-ray fluxes to the intensities of Fexvi 335 Ú and 361 Ú, Fexv
284 Ú and 417 Ú, and Mgix 368 Ú measured with SERTS. We found that
the power-law fits best cover the full range of solar conditions from
quiet Sun through active region, though not surprisingly the `cooler'
Mgix 368 Ú line proves to be a poor proxy. The quadratic polynomial
fits yield fair agreement over a large range for all but the Mgix
line. However, the linear fits fail conspicuously when extrapolated
into the quiet-Sun regime. The implications of this work for the Heii
304 Ú line formation problem are also briefly considered.
Title: HS0507+0434: a double DA degenerate with a ZZCeti component
Authors: Jordan, S.; Koester, D.; Vauclair, G.; Dolez, N.; Heber,
U.; Hagen, H. -J.; Reimers, D.; Chevreton, M.; Dreizler, S.
Bibcode: 1998A&A...330..277J
Altcode:
HS0507+0434 and HS2240+1234 are two new common proper motion pairs of
DA white dwarfs, discovered by the Hamburg Quasar Survey. Our model
atmosphere analysis shows that HS0507+0434A has an effective temperature
of 20000K and is remarkably young (tau_cool < 1Gyr) compared to the
average cooling time of all known wide double degenerates (~ 3Gyr). The
cooler B component of HS0507+0434 is particularly interesting; the
determination of the atmospheric parameters is complicated by the
strong dependence of the solution on the details of the treatment of
convection. Only those parameterizations of mixing length theory are
consistent with all observations (especially the magnitude difference
between the components), which lead to an intermediate efficiency of the
convective flux. In the standard version of the mixing length theory
this corresponds to a mixing length parameter of l/H_p = 1.75 - 2.0,
where H_p is the pressure scale height. This result does not depend on
the model atmosphere code and is in agreement with previous studies of
convection in DA white dwarfs; there are, however, slightly different
formulations of the MLT in use, which achieve the same efficiency at
different values of l/H. These versions are discussed and compared
in the paper. The result of our analysis (T_eff=11900K, log g=8)
places the B component into the ZZCeti instability strip, where DA
white dwarfs are pulsating non-radially. Photometric observations
have now confirmed that HS0507+0434 is variable and identified 3 or
4 fundamental g-modes in the Fourier spectrum. Based on observations
collected at the German-Spanish Astronomical Center (DSAZ) at Calar
Alto, Spain, at the European Southern Observatory, La Silla, Chile,
with the International Ultraviolet Explorer Satellite, and at the
Observatoire de Haute Provence (CNRS), France.
Title: The Helium Spectrum in the Quiet Sun: The January 16/17 and
May 7-13 1997 Coordinated SOHO/Ground-Based Observational Campaigns
Authors: Andretta, Vincenzo; Jordan, Stuart D.; Muglach, Karin;
Garcia, Adriana; Jones, Harrison P.; Penn, Matthew J.; Soltau, Dirk
Bibcode: 1998ASPC..155..336A
Altcode: 1998sasp.conf..336A
No abstract at ADS
Title: Investigating the Formation of the Helium Spectrum in the
Solar Atmosphere
Authors: Andretta, Vincenzo; Jordan, Stuart D.; Muglach, Karin;
Garcia, Adriana; Jones, Harrison P.; Soltau, Dirk
Bibcode: 1998ASPC..154..559A
Altcode: 1998csss...10..559A
We present the first results of coordinated observations with SOHO
(Solar Heliospheric Observatory) and ground-based observatories aimed
at investigating the mechanisms responsible for the formation of helium
lines in the quiescent solar atmosphere. The observations described
here were taken on 7-13 May 1997; the SOHO instruments involved were
CDS, SUMER and EIT, while ground-based support was provided by the
German Vacuum Tower Telescope on Tenerife (He 1 lambda10830 and Ca 2
lambda8498 spectra-spectroheliograms), Coimbra Solar Observatory (Hα
spectroheliograms), and NASA/NSO Vacuum Tower Telescope on Kitt Peak
(Ca 2 lambda8542 spectra-spectroheliograms and polarimetry).
Title: The Record Breaking Magnetic White Dwarf RE J0317-853
Authors: Burleigh, M. R.; Jordan, S.
Bibcode: 1998AAS...191.1511B
Altcode: 1998BAAS...30..756B
RE J0317-853 is a strongly magnetic white dwarf discovered as an EUV
source by the ROSAT Wide Field Camera (WFC). The average optical and
far-UV spectrum of this star could be matched by a dipole model,
off-centred by 0.2 stellar radii in the direction of the southern
magnetic pole, with a mean field strength of 340MG (Barstow, Jordan,
Burleigh et al., 1995, MNRAS, 277, 971). Since RE J0317-853 has a
cool DA white dwarf companion (LB 9802) just 16" away, we could use
its atmospheric parameters (T=16,030+/-230K, log g=8.19+/-0.05)
as an additional constraint on the parameters of RE J0317-853,
assuming both stars lie at the same distance (highly likely). We
found that RE J0317-853 is the hottest known magnetic white dwarf (T ~
50,000K), and probably the most massive white dwarf ever discovered (
~ 1.35M_sun). In addition, high speed photometry has shown that the
optical brightness of RE J0317-853 varies almost sinusoidal with a
period of 725 seconds. The only possible explanation is a change in
surface brightness with rotation, and thus RE J0317-853 is spinning
faster than any known isolated white dwarf. In order to analyse the
magnetic field in detail, we have obtained time resolved far-UV
spectra with HST/FOS, time resolved spectro-polarimetry with the
Anglo-Australian Telescope (AAT), and additional data with the EUVE,
Orfeus, and ROSAT satellites. We find that the magnetic field structure
is actually extremely complex, and cannot in fact be described by
the offset dipole model used previously to fit the mean spectrum. A
preliminary analysis of the observations with new theoretical models
shows that the data can be best represented by a magnetic field
with two distinct field strengths, of ~200MG and ~500MG, on different
hemispheres. We also identify one intriguing absorption feature at 1170{
Angstroms} as a dipole forbidden component of Lyman alpha (1sO-2sO),
which is only possible due to the simultaneous presence of a magnetic
and electric field.
Title: White Dwarfs in the Hamburg Quasar Survey
Authors: Homeier, D.; Koester, D.; Hagen, H. -J.; Jordan, S.; Heber,
U.; Engels, D.; Reimers, D.; Dreizler, S.
Bibcode: 1998AGAb...14..148H
Altcode: 1998AGM....14..P98H
The spatial distribution and the luminosity function of white dwarfs
provide important information on stellar evolution and the structure
and age of the Galactic disk. A total of about 2 200 white dwarfs is
known to date. The Hamburg Quasar Survey (HQS) has the capability to
substantially enlarge this number and to provide an optically selected
sample of white dwarfs not relying on EUV/X-ray emission. The HQS,
covering 14 000 deg^2 of the northern sky, has produced objective prism
spectra of several thousand stellar UV-excess sources. We expect to be
able to identify 2 000-3 000 white dwarfs down to a limiting magnitude
of B=17_{\cdot}m5 from this database. The spectra also
allow a rough estimate of Teff by the Balmer line strengh
of DA white dwarfs. Follow-up observations of hot star candidates
in selected fields of the survey and comparisons with the catalogue
of known white dwarfs have shown that DAs with temperatures down to,
and below, the ZZ-Ceti instability strip (~ 11 000 K) are found. The
number density of DA per deg^2 found within the magnitude range of the
Palomar-Green survey (B <= 16_{\cdot}m4) was higher than
estimated from that survey. The 80 DA white dwarfs discovered by the
follow-up spectroscopy have been analyzed using LTE model atmospheres to
determine Teff and \log g, from which the mass distribution,
luminosities and photometric distances can be derived.
Title: Interpreting the growth and destruction of a large
long-duration solar active-region complex
Authors: Bumba, V.; Garcia, A.; Jordan, S.
Bibcode: 1998A&A...329.1138B
Altcode:
In a companion paper, we show that the large limb flare and coronal
mass ejection of July 9, 1982, and other energetic events that followed
through September 4, 1982, represent the final phase in the evolution
of a large active-region complex (Jordan et al. 1997). In this paper,
we review the long-duration evolution of this complex. We begin by
showing that, before its final phase, new activity in the form of
renewed flux continued to appear for nearly two years, progressively
complicating the field topology. Observations suggest that the source
of this flux rotated almost as a rigid body. Evidence is presented
that, during the final phase of large-scale eruptions, either the
connection with the underlying source of flux is broken, or the source
itself has changed. After the flare and CME of September 4, 1982, the
magnetic field topology of the entire complex was greatly simplified,
and the area of former activity was replaced by a large coronal hole. We
conclude that this evolution and destruction of a large long-duration
active-region complex is a characteristic feature of how the global
magnetic field of the Sun changes during the solar cycle.
Title: Magnetic White Dwarfs: Observations in Cosmic Laboratories
Authors: Jordan, S.
Bibcode: 1998amse.conf....9J
Altcode:
No abstract at ADS
Title: Coordinated Observations with SOHO/CDS and SERTS
Authors: Thompson, W. T.; Thomas, R. J.; Davila, J. M.; Jordan, S. D.;
Brosius, J. W.
Bibcode: 1998AAS...191.7316T
Altcode: 1998BAAS...30..758T
On November 18, 1997, coordinated observations were made between the
Coronal Diagnostic Spectrometer (CDS) aboard the Solar and Heliospheric
Observatory (SOHO), and with the Solar Extreme-ultraviolet Rocket
Telescope and Spectrograph (SERTS). One of the primary goals of this
sounding rocket flight was to serve as a calibration underflight
for SOHO. SERTS observes resolved spectra over most of the short
wavelength channel of the CDS Normal Incidence Spectrograph, as well
as the He II 304 Angstroms line which is observed by CDS in second
order in the long wavelength channel. Observations were also made of
the full sun with the SOHO Extreme ultraviolet Imaging Telescope (EIT)
in its 304 Angstroms channel, allowing coalignment between all three
instruments. EIT also serves as a transfer standard of the alignment
to other full-sun observations. We will report on the status of the
data analysis from the SERTS-97 flight, and its comparison to CDS.
Title: Comparison of NSO/KPVT 1083 NM and SOHO/CDS/SUMER Observations
of a Coronal Hole.
Authors: Jones, H. P.; Andretta, V.; Jordan, S. D.; Penn, M. J.
Bibcode: 1997AAS...191.7304J
Altcode: 1997BAAS...29.1321J
As part of SOHO Joint Observing Program 16 to study the solar formation
of Helium, coordinated observations of a coronal hole were obtained
on 17 Jan 97. In this paper, we compare the NSO/KPVT full-disk 1083 nm
spectroheliogram and a time sequence of spectra-spectroheliograms of the
coronal hole near the south solar pole with approximately cospatial and
cotemporal SOHO spatial-spectral data taken in He I (58.4 nm, CDS and
SUMER) and He II 30.4 nm (CDS) together with several transition-region
and coronal lines of CIII, OIII, OIV, MgIX, MgX, SiIX, and SiXII. We
have previously reported on correlations of line intensities. Here
we concentrate as well on Doppler shifts and, in particular, line
asymmetry in the He I 1083 nm line which shows augmented absorption
in the blue wing of the line within the coronal hole in the same sense
as reported by Dupree, Penn, and Jones (1996, ApJ 467, L121).
Title: Formation of the Helium II 304 Angstroms Line in the Solar
Atmosphere
Authors: Jordan, S. D.; Andretta, V.
Bibcode: 1997AAS...19112003J
Altcode: 1997BAAS...29.1402J
The problem of the formation of the principle members of the resonance
series of He I and He II at 584 Angstroms and 304 Angstroms remains
a major unsolved problem of the solar atmosphere. Nevertheless,
thanks to observations from the Goddard Solar Extreme Ultraviolet
Rocket Telescope and Spectrograph (SERTS) and from the ESA/NASA
SOHO mission, we now have a data base to address this problem and,
hopefully, to solve it for the quiet atmosphere. This talk will briefly
review alternatives for helium resonance line formation in the Sun,
and will offer a few examples of observations that promise to help
discriminate among them. Specifically, assuming electron collisional
excitation is responsible for the 304 Angstroms line in the quiet Sun,
supported by our earlier studies, evidence from SERTS and SOHO will
be discussed in support of 'velocity redistribution' of the emitting
ions in producing the observed profiles and fluxes.
Title: Spectroscopy of hydrogen-rich white dwarfs from the Hamburg
Quasar Survey.
Authors: Homeier, D.; Jordan, S.; Koester, D.; Hagen, H. -J.
Bibcode: 1997AGAb...13..215H
Altcode:
No abstract at ADS
Title: RE J0317-853: a magnetic white dwarf holding many records.
Authors: Jordan, S.
Bibcode: 1997AGAb...13..216J
Altcode:
No abstract at ADS
Title: Interpreting the Large Limb Eruption of July 9, 1982
Authors: Jordan, Stuart; Garcia, Adriana; Bumba, Vaclav
Bibcode: 1997SoPh..173..359J
Altcode:
A time series of K3 spectroheliograms taken at the Coimbra Observatory
exhibits an erupting loop on the east limb on July 9, 1982 in active
region NOAA 3804. The Goddard SMM Hard X-Ray Burst Spectrometer
(HXRBS) observations taken during this period reveal a hard X-ray flare
occurring just before the loop eruption is observed, and SMS-GOES soft
X-ray observations reveal a strong long-duration event (LDE) following
the impulsive phase of the flare. A Solwind coronagram exhibits a
powerful coronal mass ejection (CME) associated with the erupting
loop. Hα flare and prominence observations as well as centimeter and
decimeter radio observations of the event are also reviewed. A large,
north-south-oriented quiescent prominence reported within the upper
part of the CME expansion region may play a role in the eruption as
well. The spatial and temporal correlations among these observations are
examined in the light of two different current models for prominence
eruption and CME activation: (1) The CME is triggered by the observed
hard X-ray impulsive flare. (2) The CME is not triggered by a flare,
and the observed soft X-ray flare is an LDE due to reconnection within
the CME `bubble'. It is concluded that this event is probably of a
`mixed' type that combines characteristics of models (1) and (2). The
July 9 event is then compared to three other energetic CME and flare
eruptions associated with the same active-region complex, all occurring
in the period July 9 through September 4, 1982. It is noted that these
four energetic events coincide with the final evolutionary phase of a
long-lasting active-region complex, which is discussed in a companion
paper (Bumba, Garcia, and Jordan, 1997). The paper concludes by
addressing `the solar flare myth' controversy in the light of this work.
Title: X-ray properties of symbiotic stars. II. Systems with
colliding winds.
Authors: Muerset, U.; Wolff, B.; Jordan, S.
Bibcode: 1997A&A...319..201M
Altcode:
60% of the known galactic symbiotic stars are sufficiently X-ray
bright to be detected in pointed ROSAT PSPC observations. We present
observations of 16 symbiotic stars. We encounter three classes of
pulse height distibutions: α) supersoft emission from the atmosphere
of the hot star, β) emission from an optically thin plasma with a
temperature of a few 10^6^K, and γ) even harder emission, as from an
accreting neutron star. In the present Paper we analyze the objects
of type β in more detail. We find plasma temperatures ranging from
3x10^6^K to 15x10^6^K and luminosities from 2x10^-4^Lsun_
to 0.4Lsun_.
Title: Temperature determination of the cool DO white dwarf HD
149499B from EUVE observations.
Authors: Jordan, S.; Napiwotzki, R.; Koester, D.; Rauch, T.
Bibcode: 1997A&A...318..461J
Altcode: 1996astro.ph..5007J
We present a LTE model atmosphere analysis of the EUVE medium and
long wavelength spectrum of the cool DO white dwarf HD149499B. This
observation in the spectral range 230-700Å supplements a previous
analysis of an ORFEUS spectrum between 912 and 1170Å which yielded
the atmospheric parameters T_eff_=49500+/-500K and logg=7.97+/-0.08
and a hydrogen-to-helium number ratio of 0.22+/-0.11. The EUVE data
are in full agreement with the ORFEUS result and allow a more precise
determination of the effective temperature (T_eff_=49500+/-200K) and
the interstellar hydrogen column density (N_H_=7x10^18^cm^-2^). None
of the features in the EUVE spectrum could be identified with any
additional absorber besides helium. Exploratory calculations with fully
metal blanketed LTE model atmospheres show that the metal abundances
predicted by current diffusion theory are clearly at variance with
the observed spectrum.
Title: New results of magnetic white dwarf spectroscopy
Authors: Jordan, S.
Bibcode: 1997ASSL..214..397J
Altcode: 1997whdw.work..397J
No abstract at ADS
Title: First Results of the SUMER Telescope and Spectrometer on SOHO -
I. Spectra and Spectroradiometry
Authors: Wilhelm, K.; Lemaire, P.; Curdt, W.; Schühle, U.; Marsch, E.;
Poland, A. I.; Jordan, S. D.; Thomas, R. J.; Hassler, D. M.; Huber,
M. C. E.; Vial, J. -C.; Kühne, M.; Siegmund, O. H. W.; Gabriel, A.;
Timothy, J. G.; Grewing, M.; Feldman, U.; Hollandt, J.; Brekke, P.
Bibcode: 1997SoPh..170...75W
Altcode:
SUMER - the Solar Ultraviolet Measurements of the Emitted Radiation
instrument on the Solar and Heliospheric Observatory (SOHO) - observed
its first light on January 24, 1996, and subsequently obtained a
detailed spectrum with detector B in the wavelength range from 660
to 1490 Å (in first order) inside and above the limb in the north
polar coronal hole. Using detector A of the instrument, this range
was later extended to 1610 Å. The second-order spectra of detectors
A and B cover 330 to 805 Å and are superimposed on the first-order
spectra. Many more features and areas of the Sun and their spectra
have been observed since, including coronal holes, polar plumes and
active regions. The atoms and ions emitting this radiation exist at
temperatures below 2 × 106 K and are thus ideally suited
to investigate the solar transition region where the temperature
increases from chromospheric to coronal values. SUMER can also be
operated in a manner such that it makes images or spectroheliograms
of different sizes in selected spectral lines. A detailed line profile
with spectral resolution elements between 22 and 45 mÅ is produced for
each line at each spatial location along the slit. From the line width,
intensity and wavelength position we are able to deduce temperature,
density, and velocity of the emitting atoms and ions for each emission
line and spatial element in the spectroheliogram. Because of the high
spectral resolution and low noise of SUMER, we have been able to detect
faint lines not previously observed and, in addition, to determine
their spectral profiles. SUMER has already recorded over 2000 extreme
ultraviolet emission lines and many identifications have been made on
the disk and in the corona.
Title: High resolution solar ultraviolet measurements
Authors: Lemaire, P.; Wilhelm, K.; Schühle, U.; Curdt, W.; Poland,
A. I.; Jordan, S. D.; Thomas, R. J.; Hassler, D. M.; Vial, J. -C.
Bibcode: 1997AdSpR..20.2249L
Altcode:
The increase of our understanding of the processes acting in the solar
corona and maintaining it is strongly dependent on the quality of the
data that are obtained to check theories. The fine structure of the
solar atmosphere seen from the photosphere and extending to the hottest
parts of the corona requires data with high resolution in all parameter
space (angular, spectral and temporal). To constrain the hypotheses that
are proposed to describe the solar corona, it is necessary to establish
an accurate energy budget taking into account the processes which are
acting from the chromosphere to the corona. Some requirements can be
established and compared with the data collected so far (or about to
be collected) with the present SUMER (Solar Utraviolet Measurements
of Emitted Radiations) instrumentation.
Title: Investigating the Formation of the Helium Spectrum with
Coordinated SOHO/Kitt Peak/Sacramento Peak Observations
Authors: Andretta, V.; Jordan, Stuart D.; Jones, Harrison P.; Penn,
Matthew J.
Bibcode: 1997ESASP.404..163A
Altcode: 1997cswn.conf..163A
No abstract at ADS
Title: Understanding the Hell 304 Å Resonance Line in the Sun
Authors: Jordan, S.; Andretta, V.; Garcia, A.; Falconer, D.
Bibcode: 1997ESASP.404..439J
Altcode: 1997cswn.conf..439J
No abstract at ADS
Title: First Results of the SUMER Telescope and Spectrometer on SOHO -
II. Imagery and Data Management
Authors: Lemaire, P.; Wilhelm, K.; Curdt, W.; SchÜle, U.; Marsch,
E.; Poland, A. I.; Jordan, S. D.; Thomas, R. J.; Hassler, D. M.; Vial,
J. C.; KÜhne, M.; Huber, M. C. E.; Siegmund, O. H. W.; Gabriel, A.;
Timothy, J. G.; Grewing, M.
Bibcode: 1997SoPh..170..105L
Altcode:
SUMER - Solar Ultraviolet Measurements of Emitted Radiation - is not
only an extreme ultraviolet (EUV) spectrometer capable of obtaining
detailed spectra in the range from 500 to 1610 Å, but, using the
telescope mechanisms, it also provides monochromatic images over
the full solar disk and beyond, into the corona, with high spatial
resolution. We report on some aspects of the observation programmes
that have already led us to a new view of many aspects of the Sun,
including quiet Sun, chromospheric and transition region network,
coronal hole, polar plume, prominence and active region studies. After
an introduction, where we compare the SUMER imaging capabilities to
previous experiments in our wavelength range, we describe the results
of tests performed in order to characterize and optimize the telescope
under operational conditions. We find the spatial resolution to be
1.2 arc sec across the slit and 2 arc sec (2 detector pixels) along
the slit. Resolution and sensitivity are adequate to provide details
on the structure, physical properties, and evolution of several solar
features which we then present. Finally some information is given on
the data availability and the data management system.
Title: White dwarfs in AM Herculis systems
Authors: Gänsicke, B. T.; Beuermann, K.; de Martino, D.; Jordan, S.
Bibcode: 1997ASSL..214..353G
Altcode: 1997whdw.work..353G
No abstract at ADS
Title: A new dithered EUVE spectrum of PG 1234+482
Authors: Jordan, S.; Koester, D.; Finley, D. S.
Bibcode: 1997ASSL..214..281J
Altcode: 1997whdw.work..281J
No abstract at ADS
Title: Obituary: Richard Nelson Thomas, 1921-1996
Authors: Jordan, Stuart D.
Bibcode: 1996BAAS...28.1465J
Altcode:
No abstract at ADS
Title: Extragalactic symbiotic systems. IV. The supersoft X-ray
source SMC 3.
Authors: Jordan, S.; Schmutz, W.; Wolff, B.; Werner, K.; Muerset, U.
Bibcode: 1996A&A...312..897J
Altcode: 1996astro.ph..4076J
We present a consistent model for the UV and supersoft X-ray emission
from the symbiotic nova SMC3 (=RX J0048.4-7332). Following the
present picture of symbiotic stars, the model consists of radiation
from a hot star and an emission nebula excited by that star. The
observations were compared to theoretical models in which the
hot star's emission is calculated with the help of hydrostatic and
Wolf-Rayet-type non-LTE model atmospheres. Our analysis clearly shows
evidence for mass loss rates of several 10^-6^Msun_/yr. The
minimum effective temperature compatible with both the observed UV
and X-ray flux is about 260000K, which is higher than in any other
star analyzed with sophisticated NLTE model atmospheres. Since the
hydrostatic surface is hidden by the stellar wind no upper limit for
the temperature can be determined. However, we were able to determine
the total luminosity of a symbiotic nova with reasonable accuracy
(L_SMC3_=10^4.05+/-0.05^Lsun_). This value is well below
the Eddington limit (=~50000Lsun_). In order to reproduce
the observed energy distribution a carbon-to-helium ratio >2.10^-4^
-- leading to an absorption edge at 0.39keV -- is necessary.
Title: Discovery of four white dwarfs with strong magnetic fields
by the Hamburg/ESO Survey.
Authors: Reimers, D.; Jordan, S.; Koester, D.; Bade, N.; Koehler,
T.; Wisotzki, L.
Bibcode: 1996A&A...311..572R
Altcode: 1996astro.ph..4104R
Four magnetic white dwarfs have been found in the course of the
Hamburg/ESO Survey for bright QSOs. The objects have been selected
as QSO candidate on the basis of its blue continuum and the apparent
absence of strong hydrogen or helium lines. One star, HE1211-1707,
shows a rather fast spectral variability: both the strength and the
position of the shallow absorption features change on a time scale of
20minutes. We interpret this variability as being due to a magnetic
field on the surface of a rotating white dwarf, having a relatively
uniform magnetic field on one hemisphere and a much larger spread
of field strengths visible during other phases of the rotational
period. All attempts to determine the magnetic field structure in
detail with the help of synthetic spectra have failed so far because
the star must have a rather complicated field geometry. However, both
the optical and the UV spectra indicate that a significant part of the
surface is dominated by a magnetic field strength of about 80MG. The
spectrum of HE0127-3110 is also rotationally modulated. This star
(approximate range of magnetic fields: 85-345MG) as well as HE2201-2250
(a spectroscopic twin of HE0127-3110) and HE0000-3430 (43-118MG) could
be reasonably well reproduced with the help of theoretical spectra
calculated assuming magnetic dipoles which are offset by 0.1 and 0.2
stellar radii along the magnetic axis. This result is in agreement with
the assumption that Ap stars, also showing significant deviations from
a centered dipole, are the progenitors of magnetic white dwarfs.
Title: The Large Limb Event of July 9, 1982
Authors: Jordan, S. D.; Garcia, A.; Bumba, V.
Bibcode: 1996AAS...188.7009J
Altcode: 1996BAAS...28..939J
An erupting prominence was observed on the East solar limb on July 9,
1982 in a series of K3 spectroheliograms taken at the Solar Observatory
in Coimbra. Events associated with this eruption were observed with
the Hard X-ray Burst Spectrometer (HXRBS) on SMM and a number of other
instruments on the ground and in space including the Solwind satellite,
which observed an energetic coronal mass ejection (CME) during the
same time-frame. An impulsive flare occurred about one hour before the
rise-time of the soft X-ray long duration event (LDE) and the apparent
rise-time of the CME. This extensive set of observations permitted
a comparison of this complex flare-erupting prominence-CME-LDE with
a model proposed by Hundhausen (1994, 'Coronal Mass Ejections,' in
"The Many Faces of the Sun," Springer-Verlag). Both similarities and
differences are noted. While the start of the CME almost certainly
follows the impulsive flare, it cannot be concluded that the flare is
the 'cause' of the CME. The importance of determining the relative rise-
times for the CME and the LDE is underscored by this study. Two other
energetic events from the same active region are also discussed. It
is concluded that no one model for the phenomenon: flare-erupting
prominence-CME-LDE is satisfactory, even for these three events.
Title: DA white dwarfs in pointed observations from the ROSAT archive.
Authors: Wolff, B.; Jordan, S.; Koester, D.
Bibcode: 1996A&A...307..149W
Altcode:
87 pointed PSPC (Position Sensitive Proportional Counter) observations
of hot DA white dwarfs, available in the ROSAT public archive until the
end of 1994, have been analyzed together with Wide Field Camera (WFC)
and EXOSAT data. From the 57 objects with a significant count rate half
of the objects have a temperature below 38,000K and a virtually pure
hydrogen atmosphere. At higher temperatures most (75%) objects emit a
lower X-ray flux than predicted by hydrogen model atmospheres and must
therefore contain heavier elements as absorbers. This is probably due
to radiative acceleration which prevents these elements from sinking
inwards. We also confirmed our previous result that the PSPC detector
is a factor of two more sensitive to photons with energies below
about 0.2keV.
Title: X-ray and EUV detection of metals in the atmospheres of hot
DA white dwarfs.
Authors: Jordan, S.; Finley, D.; Koester, D.; Wolff, B.
Bibcode: 1996rftu.proc....5J
Altcode:
The authors have analyzed X-ray and EUV observations of 69 DA white
dwarfs in the framework of model atmospheres containing pure hydrogen
and under the assumption that a mixture of additional heavier absorbers
is present. The result is that most stars with Teff
⪆ 38000 K are not compatible with the assumption of pure hydrogen
atmospheres but must contain additional elements. Above about 53000 K
this is the case for all stars in the authors' sample. As an example
for high resolution spectroscopy in the EUV the authors have analyzed
the EUVE spectrum of the hot white dwarf PG 1234+482 with model
atmospheres containing metals, and could identify iron and possibly
other heavy elements in the observations. In order to quantitatively
measure the metallicity in the atmospheres of the hot white dwarfs,
they have compared the X-ray and EUV observations of 50 objects to the
predictions from a grid of models with different metal contents. As
expected from the theory of radiative levitation the hotter stars tend
to have higher metallicity. However, the observed scatter in metallicity
at a given effective temperature could not be explained by different
surface gravities only. Moreover, the element abundances are in general
lower (up to three orders of magnitude) than predicted by theory.
Title: X-Ray Properties of Symbiotic Stars: I. The Supersoft Symbiotic
Novae RR Tel and SMC3 (=RX J0048.4-7332)
Authors: Mürset, U.; Jordan, S.; Wolff, B.
Bibcode: 1996LNP...472..251M
Altcode: 1996sxrs.conf..251M; 1996LNP96.472..251M
We searched the ROSAT archive for pointed PSPC observations covering
positions of symbiotic stars. 16 systems are detected. We find
three distinct types of energy distributions, one of which is
supersoft. This class consists of seven objects, among them two
symbiotic novae, RR Tel and SMC3, which are discussed in more detail
in this paper. The supersoft emission is produced by photospheric
emission from the hot star. For RR Tel the ROSAT and IUE observations
are simultaneously reproduced with a white dwarf type atmosphere with
T eff=142 000 K. SMC3 can only be fitted with a WR-type
atmosphere with considerable mass loss (dot M ∼ 10^{ - 5} M_ odot
/yr), and a temperature in excess of T eff ≳ 260 000 K.
Title: Accretion heated magnetic white dwarfs.
Authors: Gänsicke, B. T.; Beuermann, K.; de Martino, D.; Jordan, S.
Bibcode: 1996AGAb...12...32G
Altcode:
No abstract at ADS
Title: EUVE and ORFEUS Observations of the Cool DO White Dwarf
HD 149499B
Authors: Napiwotzki, R.; Jordan, S.; Bowyer, S.; Hurwitz, M.; Koester,
D.; Rauch, T.; Weidemann, V.
Bibcode: 1996aeu..conf..241N
Altcode: 1996IAUCo.152..241N
No abstract at ADS
Title: Solar EUV spectroscopy with serts: measurements of active
and quiet Sun properties.
Authors: Brosius, J. W.; Davila, J. M.; Thomas, R. J.; Jordan, S. D.;
Monsignori-Fossi, B. C.
Bibcode: 1996uxsa.conf...83B
Altcode: 1996uxsa.coll...83B
The Solar EUV Rocket Telescope and Spectrograph (SERTS) was developed
by the Laboratory for Astronomy and Solar Physics at NASA/Goddard
Space Flight Center. It was successfully flown in 1989, 1991, 1993, and
(very recently) 1995, providing spectra and images of a variety of solar
features on each occasion. SERTS data have been used to address numerous
problems in solar physics, of which the following are discussed below:
(1) measurement of coronal temperature and density, (2) derivation
of differential emission measure distribution, (3) verification of
atomic physics parameters, (4) determination of relative elemental
abundances, (5) formation of the He II 304 Å line, (6) mass flows,
and (7) coronal magnetography.
Title: Detection of Heavy Elements in the EUVE Spectrum of a Hot
White Dwarf
Authors: Jordan, S.; Koester, D.; Finley, D.
Bibcode: 1996aeu..conf..235J
Altcode: 1996IAUCo.152..235J
No abstract at ADS
Title: SUMER - Solar Ultraviolet Measurements of Emitted Radiation
Authors: Wilhelm, K.; Curdt, W.; Marsch, E.; Schühle, U.; Lemaire,
P.; Gabriel, A.; Vial, J. -C.; Grewing, M.; Huber, M. C. E.; Jordan,
S. D.; Poland, A. I.; Thomas, R. J.; Kühne, M.; Timothy, J. G.;
Hassler, D. M.; Siegmund, O. H. W.
Bibcode: 1995SoPh..162..189W
Altcode:
The instrument SUMER - Solar Ultraviolet Measurements of Emitted
Radiation is designed to investigate structures and associated dynamical
processes occurring in the solar atmosphere, from the chromosphere
through the transition region to the inner corona, over a temperature
range from 104 to 2 × 106K and above. These
observations will permit detailed spectroscopic diagnostics of plasma
densities and temperatures in many solar features, and will support
penetrating studies of underlying physical processes, including plasma
flows, turbulence and wave motions, diffusion transport processes,
events associated with solar magnetic activity, atmospheric heating,
and solar wind acceleration in the inner corona. Specifically, SUMER
will measure profiles and intensities of EUV lines; determine Doppler
shifts and line broadenings with high accuracy; provide stigmatic
images of the Sun in the EUV with high spatial, spectral, and temporal
resolution; and obtain monochromatic maps of the full Sun and the inner
corona or selected areas thereof. SUMER will be flown on the Solar
and Heliospheric Observatory (SOHO), scheduled for launch in November,
1995. This paper has been written to familiarize solar physicists with
SUMER and to demonstrate some command procedures for achieving certain
scientific observations.
Title: RE J0317-853: the hottest known highly magnetic DA white dwarf
Authors: Barstow, M. A.; Jordan, S.; O'Donoghue, D.; Burleigh, M. R.;
Napiwotzki, R.; Harrop-Allin, M. K.
Bibcode: 1995MNRAS.277..971B
Altcode:
We report the discovery of a new highly magnetic DA white dwarf, RE
J0317-853, through its detection as an EUV source by the ROSAT Wide
Field Camera. A combination of far-UV and optical spectra indicates that
the star has an effective temperature ~=50000K, making it the hottest
known white dwarf with a measurable magnetic field. Furthermore,
the magnetic field is exceptionally intense, having a value ~=340
MG, sufficient to shift and broaden the Balmer line features almost
beyond recognition. A field of this value is also among the highest
known. While these parameters already make this star unique, we have
also found that, alone among the magnetic DA white dwarfs, it is a
large-amplitude (~=+/-0.1 mag) oscillator at optical wavelengths with
a period of 725.4s. Since there is no known pulsational instability
strip in this temperature range, the most plausible explanation is
that the modulation of the optical flux is due to rotation of the
star. If the star is at the same distance as another DA star, some 16
arcsec away, it must have an unusually small radius and, consequently,
a mass approaching the Chandrasekhar limit. The two stars would also
comprise one of only three known visual double degenerate systems with
hot white dwarf components. ROSAT data indicate that heavy elements
detected in the IUE spectrum are mainly attributable to circumstellar
material, and we suggest this may arise from a wind driven by cyclotron
radiation pressure from the intense magnetic field.
Title: Some design and performance features of SUMER: solar
ultraviolet measurements of emitted radiation
Authors: Wilhelm, Klaus; Curdt, W.; Marsh, E.; Schuehle, Udo H.;
Lemaire, Philippe; Gabriel, Alan H.; Vial, J. -C.; Grewing, Michael;
Huber, Martin C.; Jordan, S. D.; Poland, Arthur I.; Thomas, Roger J.;
Kuehne, Mikhael; Timothy, J. Gethyn; Hassler, Donald M.; Siegmund,
Oswald H.
Bibcode: 1995SPIE.2517....2W
Altcode:
The instrument SUMER (solar ultraviolet measurements of emitted
radiation) is designed to investigate structures and associated
dynamical processes occurring in the solar atmosphere from the
chromosphere through the transition region to the inner corona, over a
temperature range from 104 to 2 multiplied by 106
K and above. The observations will be performed, on board SOHO (solar
and heliospheric observatory) scheduled for launch in November 1995,
by a scanning, normal-incidence telescope/spectrometer system in
the wavelength range from 500 to 1610 angstrom. Spatial resolution
requirements compatible with the pointing stability of SOHO are less
than 1000 km corresponding to about 1-arcsec angular resolution. Doppler
observations of EUV line shifts and broadenings should permit solar
plasma velocity measurements down to 1 km s-1. We report
here on some specific features of this instrument related to its
pointing as well as its spatial and spectral resolution capabilities.
Title: Magnetism in the polar BL Hydri.
Authors: Schwope, A. D.; Beuermann, K.; Jordan, S.
Bibcode: 1995A&A...301..447S
Altcode:
We report on phase-resolved low-resolution spectrophotometry of the
magnetic cataclysmic binary BL Hyi in low, intermediate, and high
states of accretion. The cyclotron spectrum of the main accreting pole
is red and displays no resolvable cyclotron lines, which is indicative
of a low field strength in the accretion spot. This supposition is
confirmed by the detection of halo Zeeman absorption in a field of
only 12 MegaGauss (MG), one of the lowest values measured among the
polars. The effective photospheric field of the white dwarf measured
during a low state, B_eff_=~22MG is higher than in the accretion
region which is usually assumed to lie in the vicinity of one of the
magnetic poles. Thus deviations from a centered dipole field seem
to be present. Numerical synthetization of white dwarf photospheric
spectra shows that many of the observed features can be explained
by a dipole-/quadrupole combination, with both constituents having
approximately the same strength.
Title: ORFEUS observations of the DO white dwarf HD 149499B.
Authors: Napiwotzki, R.; Hurwitz, M.; Jordan, S.; Bowyer, S.; Koester,
D.; Weidemann, V.; Lampton, M.; Edelstein, J.
Bibcode: 1995A&A...300L...5N
Altcode:
We present an analysis of a hig-resolution FUV spectrum
(912...1170Angstroems) of the cool DO white dwarf HD 149499
B. Observations were performed with the Berkeley EUV/FUV spectrometer
of the ORFEUS experiment. The analysis, performed with a grid of LTE
model atmospheres, yielded the basic parameters Teff = 49500+/-500K and
log g = 7.97+/-0.08. The photospheric hydrogen Lyman lines in the FUV
spectrum indicate the presence of hydrogen: log nH/nHe =-0.65+/-0.12.The
implications of this finding for the spectral evolution of white
dwarfs are discussed. A check of the LTE assumption was performed
by a comparison with NLTE atmospheres calculated for appropriate
parameters. The interstellar components of the hydrogen Lyman lines
are used for an estimate of the hydrogen column towards the HD 149499
system: N_H_ about 1x10^19^/cm2.
Title: The ROSAT spectrum of the symbiotic nova AG Pegasi: evidence
for colliding winds.
Authors: Muerset, U.; Jordan, S.; Walder, R.
Bibcode: 1995A&A...297L..87M
Altcode:
Pointed ROSAT PSPC observations of the symbiotic nova AG Peg are
presented and analyzed. A basic analysis shows that the X-rays are
emitted by a hot - probably shock-heated - plasma with a temperature of
a few MK. We suggest that we are facing the first definite observation
of colliding winds in a symbiotic binary system. Using a one point
model, we derive for the emitting plasma a characteristic temperature of
3.5x10^6^K, a luminosity of 0.01Lsun_^bol^, and an emission
measure of 1.5x10^54^cm^-3^. A 2D hydrodynamic simulation resting on
published system parameters reproduces these results.
Title: Are Spicules Evidence for Small-scale Motions that Redistribute
HE II Ions to Produce Enhanced 304A Line Emission?
Authors: Jordan, S. D.; Davila, J. M.; Thomas, R. J.; Garcia, A.
Bibcode: 1995SPD....26..508J
Altcode: 1995BAAS...27..958J
No abstract at ADS
Title: ROSAT pointed observations of four X-ray bright DA white
dwarfs.
Authors: Wolff, B.; Jordan, S.; Bade, N.; Reimers, D.
Bibcode: 1995A&A...294..183W
Altcode:
We present pointed observations of four hot DA white dwarfs with the
ROSAT satellite. Measurements with the Position Sensitive Proportional
Counter (PSPC) and the Wide Field Camera (WFC) were analyzed in the
framework of pure hydrogen model atmospheres. The results fit well
into the picture of previous studies that objects between about 20000
and 40000K have almost pure hydrogen atmospheres, while at higher
temperatures additional absorbers are present in general. Of particular
interest are PG0824+289, PG1657+344, and PG1658+441. The former is a
close binary consisting of a DA white dwarf and a dwarf carbon star
(dC). The effective temperature of 37000K, derived from the ROSAT
observations, is very close to the value determined from IUE spectra,
which - unlike optical spectra - are not contaminated by the "cool"
dC. Therefore we conclude that the DA component of the system has a
pure hydrogen atmosphere. The magnetic DA PG1658+441 has the highest
mass (1.31Msun_) of all known single white dwarfs. Its
X-ray flux can be explained by a pure hydrogen atmosphere. An optical
spectrum of PG1657+344 reveals that this object is one of the few DA
white dwarfs with T_eff_>50000K. In this case the analysis of the
ROSAT data shows clear evidence for absorbing material besides hydrogen.
Title: Calibration of Convective Efficiency by UV Observations of
a Double Degenerate
Authors: Jordan, S.
Bibcode: 1995iue..prop.5042J
Altcode:
No abstract at ADS
Title: Two-pole accretion in the high-field polar RXJ 1938.6-4612.
Authors: Schwope, A. D.; Thomas, H. -C.; Beuermann, K.; Burwitz, V.;
Jordan, S.; Haefner, R.
Bibcode: 1995A&A...293..764S
Altcode:
We report the discovery of two systems of cyclotron emisson lines
in phase-resolved low-resolution spectra of the recently discovered
AM Herculis binary RXJ 1938.6-4612. The fieldstrengths inferred are
B_1_=~47MG and B_2_=~70-80MG, which might be indicative of a non-dipolar
field structure. The latter value is the highest found so far for
white dwarfs in cataclysmic variables. We present a spectroscopic
ephemeris of sufficient accuracy to connect our optical and ROSAT All
Sky Survey X-ray observations separated by a few years. Using this,
the X-ray bright accretion spot which is visible for less than 40%
of the binary cycle may be identified with the low-field accretion
region. The high-field spot dominates the optical lightcurve. We
find slight evidence for a quadratic term in the ephemeris,
˙(P)=(-3.4+/-2.1)x10^-9^. Low-state spectra reveal M-star features,
Zeeman absorption troughs from the white dwarf and cyclotron emission
lines originating in the high-field region. Photospheric Zeeman models
using a slightly decentered dipole along the axis, z_off_=~0.1R_wd_,
B_pole_=~60MG, fit some absorption features in the blue spectral range
and confirm the results of high-state cyclotron spectroscopy. The
implied distance to RXJ 1938.6-4612 is ~150-190pc.
Title: A Very High Magnetic Field White Dwarf Candidate
Authors: Jordan, S.
Bibcode: 1995iue..prop.5041J
Altcode:
No abstract at ADS
Title: ORFEUS and EUVE observations of the cool DO HD 149499 B
Authors: Napiwotzki, R.; Jordan, S.; Koester, D.; Weidemann, V.;
Bowyer, S.; Hurwitz, M.
Bibcode: 1995LNP...443..337N
Altcode: 1995whdw.conf..337N
No abstract at ADS
Title: Ultraviolet Spectropolarimetry of GRW+70 8247 with the HST
Faint Object Spectrograph
Authors: Allen, R. G.; Jordan, S.
Bibcode: 1994AAS...185.4606A
Altcode: 1994BAAS...26.1383A
Spectropolarimetric observations of the magnetic white dwarf GRW+70
8247 in the lambda lambda 1280--1600 range were obtained with the Faint
Object Spectrograph aboard the Hubble Space Telescope. A dramatic
increase in both the linear and circular polarization was found to
coincide with a decline in the continuum flux below 1500 Angstroms
. High levels of linear (20%) and circular (12%) polarization were
observed in the lambda lambda 1300--1400 range and were not confined
to the well-known absorption feature at 1347 Angstroms . This work is
supported by NASA grant NAG 5-1630.
Title: Analysis of ROSAT pointed observations of 15 hot DA white
dwarfs.
Authors: Jordan, S.; Wolff, B.; Koester, D.; Napiwotzki, R.
Bibcode: 1994A&A...290..834J
Altcode:
We present the results of pointed observations of hot white dwarfs
with the ROSAT PSPC detector, and through the P1 filter of the Wide
Field Camera. Model atmospheres containing hydrogen and helium, either
homogeneously mixed or chemically stratified, are used to analyze the
new data together with observations of the same objects by EXOSAT and
the ROSAT all-sky survey. We confirm the results of previous studies,
that objects between about 20000 and 40000 K have almost pure hydrogen
atmospheres while additional absorbers are present in all three objects
at higher temperatures. As a by-product we found evidence that the
ROSAT PSPC detector is a factor 2.0+/-0.3 more sensitive to very soft
X-ray photons compared to the standard calibration.
Title: A "cool" PG 1159 star discovered by the Hamburg Schmidt Survey:
NLTE analysis of HS 0704+6153.
Authors: Dreizler, S.; Werner, K.; Jordan, S.; Hagen, H.
Bibcode: 1994A&A...286..463D
Altcode:
The discovery of a new PG 1159 star by follow-up spectroscopy of
candidates selected from objective-prism plates of the Hamburg Schmidt
Survey is presented. From a NLTE model atmosphere analysis an effective
temperature of 65 000 K and a surface gravity of logg=7.0 is determined,
which together with the extreme helium abundance (H/He<1 by number)
place HS 0704+6153 in the region of hot DO white dwarfs. The high carbon
and oxygen abundances (C/He=0.2, O/He~0.05 by number), however, are
typical for PG 1159 stars. Its effective temperature is by far lower
than that of any other PG 1159 star. HS 0704+6153 therefore is in the
transition stage between the PG 1159 stars and the DO white dwarfs,
it hence is an ideal object to study the gravitational settling of
metals in helium-rich atmospheres.
Title: HE 1045-0908: a new magnetic DA white dwarf with a distinctive
Zeeman line splitting pattern
Authors: Reimers, D.; Jordan, S.; Koehler, T.; Wisotzki, L.
Bibcode: 1994A&A...285..995R
Altcode:
We report the discovery of a magnetic DA white dwarf within the
Hamburg/ESO objective prism survey for bright quasars. The new
magnetic DA HE 1045-0908 was found by automated search techniques and
classified as QSO candidate. Subsequent spectroscopy with EFOSC at the
ESO 3.6m telescope showed that Halpha_ is a triplet, while
Hbeta_ and Hgamma_ are split in a distinctive
way into several Zeeman components. A model atmosphere analysis yields
T_eff_= 9200 +/-500 K, a polar field strength of 31 +/-2 MG, and a
dipole inclination of 5deg+15deg-5deg, i.e. a nearly equator-on view.
Title: Numerical simulations of convection at the surface of a ZZ
Ceti white dwarf.
Authors: Ludwig, H. -G.; Jordan, S.; Steffen, M.
Bibcode: 1994A&A...284..105L
Altcode:
We applied two-dimensional hydrodynamics and non-grey radiative transfer
calculations to the surface layers of a hydrogen-rich white dwarf
(spectral type DA) with T_eff_=12600K and log(g)=8.0, corresponding to
a position in the HR-diagram slightly cooler than the hot boundary of
the ZZ Ceti instability strip. In our simulations the entire convection
zone including the overshoot layers is embedded in the computational box
so that we obtain a complete and detailed model of convection for this
representative object. We address the important question to what extent
models based on mixing length theory (MLT) are able to predict the
physical properties of convection. We find a rapidly (timescale ~100ms)
evolving flow pattern with fast concentrated downdrafts surrounded by
slow broad upflows of warmer material. Convection carries up to 30%
of the total flux and excites internal gravity waves by dynamical
processes associated with the merging of downdrafts. The mean entropy
gradient is reversed with respect to MLT predictions in the deeper
layers of the convection zone. Strong overshoot occurs at its upper
and lower boundary. A synthetic spectrum calculated from the mean
photospheric temperature stratification can be fitted satisfactorily
with a MLT model adopting α=1.5. At greater depth the temperature
profile approaches a model with α=4. The total depth of the convective
layers is rather small compared to values suggested by studies of the
excitation mechanism for the pulsations of DAs.
Title: A model for the X-ray spectrum of the symbiotic nova RR
Telescopii.
Authors: Jordan, S.; Murset, U.; Werner, K.
Bibcode: 1994A&A...283..475J
Altcode:
Pointed ROSAT position sensitive proportional counter (PSPC)
observations of the symbiotic nova RR Tel are presented. The PSPC pulse
height distribution exhibits a rather soft energy distribution plus
few, but significant counts at higher energies. We interprete this
as superposition of photospheric flux from the hot component of the
symbiotic binary system, and X-rays emitted by a hot plasma, probably
shocked by the colliding winds from the two binary components. For
modeling the stellar component we use black body emission, as well
as line-blanketed non-local thermodynamic equilibrium (NLTE) model
atmospheres. Additional constraints for the parameters of the hot star
are provided by UV spectra obtained with IUE and VOYAGER. The parameters
of the plasma are confined by published EINSTEIN count rates. A stellar
atmosphere model with L = 3500 solar luminosity, Teff =
142000 K, log g = 6.5, and solar abundances, complemented with emission
of several times 0.01 solar luminosity by a several 106
K hot plasma reproduces both, UV and X-ray data. For the hot star's
atmosphere, any other chemical compositions can be excluded.
Title: Analysis of pointed ROSAT observations of hot DA white dwarfs.
Authors: Wolff, B.; Jordan, S.; Koester, D.
Bibcode: 1994AGAb...10..134W
Altcode:
No abstract at ADS
Title: 'SUMER' - Solar Ultraviolet Measurements of Emitted Radiation
Authors: Wilhelm, K.; Curdt, W.; Gabriel, A. H.; Grewing, M.; Huber,
M. C. E.; Jordan, S. D.; Kuhne, M.; Lemaire, P.; Marsch, E.; Poland,
A. I.; Schuhle, U.; Thomas, R. J.; Timothy, J. G.; Vial, J. -C.
Bibcode: 1994scs..conf..619W
Altcode: 1994IAUCo.144..619W
SUMER is designed for the investigations of plasma flow characteristics,
turbulence and wave motions, plasma densities and temperatures,
structures and events associated with solar magnetic activity in the
chromosphere, the transition zone and the corona. The spatial and
spectral resolution capabilities of the instrument are considered in
some detail, and a new detector concept is introduced.
Title: Line Formation and the Intensity Enhancement of the He II
304A Line in the Solar Atmosphere
Authors: Jordan, S. D.
Bibcode: 1994scs..conf..415J
Altcode: 1994IAUCo.144..415J
Observations of He II 304 Å line profiles from the Goddard solar
EUV sounding rocket flight of May 9, 1991 are analyzed to determine
lower limits on the small scale non-thermal velocities in the regions
observed. In the quiet Sun, a lower limit of 30 km/s is obtained
over much of the spectrograph slit. It is argued that a sufficient
fraction of the He II ions will survive in their upward motions,
before collisional excitation to produce a 304 Å photon, to enhance
the computed line intensity up to the observed values.
Title: Faint Blue Stars from the Hamburg Schmidt Survey
Authors: Dreizler, Stefan; Heber, Uli; Jordan, S.; Engels, D.
Bibcode: 1994hsgh.conf..228D
Altcode:
No abstract at ADS
Title: Iron in the EUVE spectrum of PG 1234+482.
Authors: Jordan, S.; Koester, D.
Bibcode: 1994AGAb...10...60J
Altcode:
No abstract at ADS
Title: The influence of the bound-free opacity on the radiation from
magnetic DA white dwarfs.
Authors: Jordan, S.
Bibcode: 1994AGAb...10..133J
Altcode:
No abstract at ADS
Title: Analysis of pointed ROSAT observations of hot DA white dwarfs.
Authors: Wolff, B.; Jordan, S.; Koester, D.
Bibcode: 1994AGAb...10...20W
Altcode:
No abstract at ADS
Title: Analysis of the ROSAT pointed observation of the hot DA white
dwarf HS1234+4811
Authors: Jordan, S.
Bibcode: 1993AdSpR..13l.319J
Altcode: 1993AdSpR..13..319J
The ROSAT data of the hot DA white dwarf HS1234+4811 were analyzed
in the framework of three different assumptions for the structure of
the white dwarf's atmosphere. It could be excluded that the star has a
homogeneously mixed photosphere consisting of helium and hydrogen only,
but from ROSAT observations alone it is not possible to decide if the
object has a stratified atmosphere with an ultrathin hydrogen layer
(MH ≈ 7 · 10-14M⊙) on top of the
He envelope or if heavier elements are responsible for the absorption
in the soft X-ray region.
Title: Cyclotron and Zeeman spectroscopy of MR Serpentis in low and
high states of accretion.
Authors: Schwope, A. D.; Beuermann, K.; Jordan, S.; Thomas, H. -C.
Bibcode: 1993A&A...278..487S
Altcode:
Phase-resolved low-resolution spectrophotometry of the polar MR Ser
obtained during states of low and high accretion reveals cyclotron line
emission as well as Balmer line Zeeman absorption. At both occasions
the cyclotron lines move with phase. The whole system of cyclotron
lines appears wavelength- and phase-shifted when the system switches
from the high to the low state. These shifts indicate a migration
of the emission/accretion region backwards in phase and towards the
rotational pole at the state of reduced accretion rate. During the
high accretion state stationary Zeeman features are seen against
the bright cyclotron background. Both, cyclotron emission lines and
Zeeman absorption lines yield the same field strength, B = 24 - 25
MG, indicating the coexistence of cool halo material and hot emitting
plasma. The Zeeman aborption lines observed in the low state are of
photospheric origin. At times one may recognize the complete set of
Zeeman components of H-alpha. The effective photospheric field strength
varies between 27.3 MG and 28.5 MG at spectroscopic phases 0.0 and 0.5,
respectively. The photospheric Zeeman lines are much narrower than
observed in other magnetic white dwarfs of comparable field strength
and much narrower than expected for a centered dipolar field and a
uniformly emitting photosphere. A spot model seems not be viable,
hence, the field structure is clearly and not simply dipolar. Model
calculations reveal a strongly decentered dipolar (doff =
0.3 Rwd) or the equivalent. Our analysis is facilitated by
the spectroscopic identification of the secondary star in MR Ser. The
determination of its spectral type as late M-dwarf (M5 - M6) allows the
distance to be estimated, d = 139 +/- 13 pc. Radial velocity variations
of photospheric absorption lines as well as quasichromospheric emission
lines are used to determine the system geometry and the white dwarf
mass, Mwd approx. 0.5 solar mass.
Title: Analysis of the DA white dwarf HZ 43A and its companion star.
Authors: Napiwotzki, R.; Barstow, M. A.; Fleming, T.; Holweger, H.;
Jordan, S.; Werner, K.
Bibcode: 1993A&A...278..478N
Altcode:
The DA white dwarf HZ 43 A (WD 1314+293) is analyzed based on a newly
obtained optical spectrogram. We demonstrate that the derived parameters
Teff = 49.000 K and log g = 7.7 are in agreement with the
observed Ly-alpha line, the slope of the UV continuum, and the measured
trigonometric parallax. The EXOSAT spectrograms of Paerels et al. (1986)
are used to obtain upper limits for the atmospheric abundance of helium,
carbon, nitrogen, and oxygen of HZ 43 A by applying the new parameters
and up-to-date Non Local Thermodynamic Equilibrium (NLTE) model
atmospheres. The result is discussed within the framework of diffusion
calculations. It turns out that the resulting abundances of the CNO
elements are below the predictions of theory making HZ 43 A an unique
object. A red/near-infrared spectrum of the companion star HZ 43 B is
used to reclassify it and to estimate temperature and metallicity. We
calculate EUV fluxes from models with the derived stellar parameters
and use them to check the flux calibrations of EXOSAT and ROSAT. The
agreement between predicted and measured count rates is reasonable
for the ROSAT-Wide Field Camera (WFC) filters. Most EXOSAT photometric
filters exhibit deviations. These are marginally consistent with our
error limits for the LX 3000, LX 4000, and the PPL filters. The Al/P
calibration is in error. Discrepant results are obtained for the EXOSAT
spectrograph and the ROSAT Position Sensitive Proportional Counter
(PSPC). These inconsistencies may cause systematic errors, if for
instance PSPC measurements are combined with WFC data for an analysis.
Title: Chromospheric Heating by Acoustic Shock Waves
Authors: Jordan, Stuart D.
Bibcode: 1993ApJ...414..337J
Altcode:
Work by Anderson & Athay (1989) suggests that the mechanical
energy required to heat the quiet solar chromosphere might be due to
the dissipation of weak acoustic shocks. The calculations reported
here demonstrate that a simple picture of chromospheric shock
heating by acoustic waves propagating upward through a model solar
atmosphere, free of both magnetic fields and local inhomogeneities,
cannot reproduce their chromospheric model. The primary reason is
the tendency for vertically propagating acoustic waves in the range
of allowed periods to dissipate too low in the atmosphere, providing
insufficient residual energy for the middle chromosphere. The effect
of diverging magnetic fields and the corresponding expanding acoustic
wavefronts on the mechanical dissipation length is then discussed as a
means of preserving a quasi-acoustic heating hypothesis. It is argued
that this effect, in a canopy that overlies the low chromosphere,
might preserve the acoustic shock hypothesis consistent with the
chromospheric radiation losses computed by Anderson & Athay.
Title: Correlation of He II lyman alpha with He I 10830 Å, and with
chromospheric and EUV coronal emission
Authors: Thompson, W. T.; Neupert, W. M.; Jordan, S. D.; Jones, H.;
Thomas, R. J.; Schmieder, B.
Bibcode: 1993SoPh..147...29T
Altcode:
This paper describes the results of comparing SERTS-3 images obtained
in the transition region line of HeII 304 å with chromospheric HeI
10830 å absorption, with strong coronal lines of MgIX 368 å, FeXV
284 å and 417 å, and FeXVI 335 å and 31 å, with Hα, with CaII
8542 å, and with magnetograms in FeI 8688Hα. All of the images are
illustrated, and the image reconstruction techniques used are described
and evaluated. The high correlation of the HeII 304 å and HeI 10830
å images, originally found by Harvey and Sheeley (1977), is confirmed
and is put on a quantitative basis. We find that the supergranulation
network has greater contrast, and that filaments appear darker, in
10830 å than in 304 å. In active regions, the 304 å line follows more
closely the behavior of Hα and CaII 8542 å than the 10830 å line.
Title: HS 0209+0832 : a DAB white dawrf with a temperature fittinginto
the DB gap.
Authors: Jordan, S.; Heber, U.; Engels, D.; Koester, D.
Bibcode: 1993A&A...273L..27J
Altcode:
The white dwarf H50209+0832 (B ≍13m.9), belonging to
the sparse class of spectral type DAB, was discovered by follow-up
spectroscopy of candidates selected from objective- prism plates of
the Hamburg Schmidt sky survey. An analysis of the optical spectrum,
clearly showing the He I λ4471 line besides the Balmer lines, yields
a He/H ratio of 2% and an effective temperature of 36000 K, which
could be confirmed by lUE observations. Among the hybrid DAB stars,
key objects for an understanding of the DA/non DA sequences, H50209+0832
is particularly interesting since its temperature lies well in the "DB
gap" between 28000 and 45000 K. Compared to a homogeneously mixed H+He
atmosphere a stratified atmosphere with a hydrogen layer mass of about
5 × 10-16 Msun in diffusion equilibrium with the
underlying helium envelope does not give an equally satisfying fit to
the observed spectrum. So we conclude that diffusion equilibrium is not
yet reached, possibly because meridional streams prevent gravitational
separation or accretion from the interstellar medium has occurred
only recently. This may also explain the occurrence of the C IV line
at 1549Å. The alternative interpretation of H50209+0832 as a binary
DA+DB appears less likely but cannot be ruled out completely.
Title: SUMER - Solar Ultraviolet Measurements of Emitted Radiation
Authors: Wilhelm, K.; Curdt, W.; Marsch, E.; Schuehle, U.; Gabriel,
A. H.; Lemaire, P.; Vial, J. -C.; Grewing, M.; Huber, M. C. E.;
Jordan, S. D.; Poland, A. I.; Thomas, R. J.; Kuehne, M.; Timothy, J. G.
Bibcode: 1993BAAS...25.1192W
Altcode:
No abstract at ADS
Title: Coronal Radiation and Formation of the He II 304 Å Line
Authors: Jordan, S. D.; Thomas, R. J.; Neupert, W. M.; Thompson, W. T.
Bibcode: 1993BAAS...25Q1211J
Altcode:
No abstract at ADS
Title: Solar Coronal Observations and Formation of the He II 304
Angstrom Line
Authors: Jordan, S. D.; Thompson, W. T.; Thomas, R. J.; Neupert, W. M.
Bibcode: 1993ApJ...406..346J
Altcode:
Although a large body of recent work supports the formation of the He
II 304 A resonance line by collisional excitation in the quiet sun, the
formation mechanism is less clear in strong coronal active regions and
flares. The 1989 May 5 flight of the Goddard Solar Extreme Ultraviolet
Rocket Telescope and Spectrograph (SERTS-3) provided a data set that is
well suited to addressing this question. This paper develops a method
of assessment of the line formation mechanism that is based on simple
non-LTE theory and is applied to these data. The results support the
conclusion of other authors that the 304 A line is formed by collisional
excitation in the quiet sun, but that photoionization-recombination
(p-r) may play a significant role in coronal active regions, and that
p-r is important, and may even be predominant, in many flares.
Title: Numerical simulations of convection at the surface of a ZZ
Ceti white dwarf.
Authors: Ludwig, H. -G.; Jordan, S.; Steffen, M.
Bibcode: 1993AGAb....9..147L
Altcode:
No abstract at ADS
Title: X-ray and EUV analysis of white dwarfs.
Authors: Jordan, S.; Wolff, B.; Napiwotzki, R.
Bibcode: 1993AGAb....9..149J
Altcode:
No abstract at ADS
Title: Faint blue stars from the Hamburg Schmidt Survey.
Authors: Dreizler, S.; Heber, U.; Jordan, S.
Bibcode: 1993AGAb....9..152D
Altcode:
No abstract at ADS
Title: Analysis of magnetic white dwarfs.
Authors: Jordan, S.
Bibcode: 1993AGAb....9..148J
Altcode:
No abstract at ADS
Title: The accreting magnetic white dwarf in MR Ser
Authors: Schwope, A. D.; Jordan, S.; Beuermann, K.
Bibcode: 1993ASIC..403..381S
Altcode: 1993wdao.conf..381S
No abstract at ADS
Title: PG 0824+289 : a dwarf carbon star with a visible white dwarf
companion.
Authors: Heber, U.; Bade, N.; Jordan, S.; Voges, W.
Bibcode: 1993A&A...267L..31H
Altcode:
We report the identification of PG0824+289 with a unique double-lined
spectroscopic binary consisting of a hot DA white dwarf and a dwarf
carbon star. Balmer line emission and possible spectrum variability
indicate a close system. A model atmosphere analysis of the hot DA
star results in T(eff) = 40,000 K and Mv = 9.2 m. The dwarf carbon star
contributes 25 percent to the (Greenstein) v magnitude of 14.22 m from
which an absolute magnitude of Mv = 10.4 m results. It is only the sixth
dwarf carbon star discovered so far and the first one in a double-lined
spectroscopic binary. It bears some resemblance to the prototype carbon
dwarf G77-61 and is the first system that allows the binary model for
the origin of the dwarf carbon stars to be tested in detail. While all
other known dC stars belong to population II, the small proper motion
of PG0824+289 indicates that it is a population I star.
Title: First numerical simulations of convection at the surface of
a ZZ Ceti white dwarf
Authors: Ludwig, H. -G.; Jordan, S.; Steffen, M.
Bibcode: 1993ASIC..403..471L
Altcode: 1993wdao.conf..471L
No abstract at ADS
Title: A first analysis of ROSAT pointed observations of two DA
white dwarfs
Authors: Jordan, S.; Napiwotzki, R.; Werner, K.; Koester, D.
Bibcode: 1993ASIC..403..177J
Altcode: 1993wdao.conf..177J
No abstract at ADS
Title: White dwarfs from the Hamburg Schmidt survey
Authors: Jordan, S.; Heber, U.
Bibcode: 1993ASIC..403...47J
Altcode: 1993wdao.conf...47J
No abstract at ADS
Title: Analysis of three magnetic DA white dwarfs
Authors: Jordan, S.
Bibcode: 1993ASIC..403..333J
Altcode: 1993wdao.conf..333J
No abstract at ADS
Title: Cataclysmic variables and related objects
Authors: Hack, Margherita; Ladous, Constanze; Jordan, Stuart D.;
Thomas, Richard N.; Goldberg, Leo; Pecker, Jean-Claude
Bibcode: 1993NASSP.507.....H
Altcode: 1993cvro.nasa.....H; 1993QB835.H27......
No abstract at ADS
Title: Cyclotron and Zeeman Spectroscopy of MR SER in a Low State
of Accretion
Authors: Schwope, Axel D.; Jordan, S.; Beuermann, K.
Bibcode: 1993AnIPS..10..312S
Altcode:
No abstract at ADS
Title: SUMER: temperatures, densities, and velocities in the outer
solar atmosphere.
Authors: Lemaire, P.; Wilhelm, K.; Axford, W. I.; Curdt, W.; Gabriel,
A. H.; Grewing, M.; Huber, M. C. E.; Jordan, S. D.; Kuehne, M.;
Marsch, E.; Poland, A. I.; Richter, A. K.; Thomas, R. J.; Timothy,
J. G.; Vial, J. C.
Bibcode: 1992ESASP.348...13L
Altcode: 1992cscl.work...13L
The SUMER instrumentation, that will be mounted on the SOHO spacecraft,
is in development under MPAE leadership. It has some capability
to improve the solar angular resolution and the spectral resolution
already obtained in the far UV to the extreme UV, corresponding to the
temperature range between 104 and a few 106K. The
authors give some insights into the SUMER spectrometer that is developed
to study the dynamics and to infer temperatures and densities of the
low corona and the chromosphere-corona transition zone in using the
50 - 160 nm wavelength range. First, they recall the SUMER scientific
goals and the technics used. Then, after a brief description of the
instrumentation the expected performances are described. The way the
observations can be conducted is emphasized and it is shown how SUMER
is operated in coordination with other SOHO instrumentations and in
cooperation with ground-based observations.
Title: Models of white dwarfs with high magnetic fields.
Authors: Jordan, S.
Bibcode: 1992A&A...265..570J
Altcode:
A novel program for calculating the theoretical spectra and wavelength
dependence degrees of the linear and circular polarization for magnetic
white dwarfs with hydrogen atmospheres has been developed. Using newer
data for the decay times of magnetic fields in white dwarfs, the effect
of the Lorentz forces on the hydrostatic structure of the atmosphere
is reevaluated, demonstrating that the effect is smaller by a factor
of 8 than previously calculated by Landstreet. As an application, new
synthetic spectra for the high field object Grw+70 deg 8247 have been
calculated, confirming the main results of Wickramasinghe and Ferrario
(1988) (a polar field strength Bp = 320 MG).
Title: "SUMER" - Solar Ultraviolet Measurements of Emitted Radiation.
Authors: Wilhelm, K.; Axford, W. I.; Curdt, W.; Gabriel, A. H.;
Grewing, M.; Huber, M. C. E.; Jordan, S. D.; Kühne, M.; Lemaire, P.;
Marsch, E.; Poland, A. I.; Richter, A. K.; Thomas, R. J.; Timothy,
J. G.; Vial, J. C.
Bibcode: 1992eocm.rept..225W
Altcode:
The experiment Solar Ultraviolet Measurements of Emitted Radiation
(SUMER) is designed for the investigations of plasma flow
characteristics, turbulence and wave motions, plasma densities
and temperatures, structures and events associated with solar
magnetic activity in the chromosphere, the transition zone and the
corona. Specifically, SUMER will measure profiles and intensities
of extreme ultraviolet (EUV) lines emitted in the solar atmosphere
ranging from the upper chromosphere to the lower corona; determine line
broadenings, spectral positions and Doppler shifts with high accuracy;
provide stigmatic images of selected areas of the Sun in the EUV with
high spatial, temporal and spectral resolution and obtain full images of
the Sun and the inner corona in selectable EUV lines, corresponding to a
temperature range from 104 to more than 1.8×106K.
Title: The MIT high resolution X-ray spectroscopy instruments on AXAF
Authors: Canizares, C. R.; Dewey, D.; Galton, E. B.; Markert, T. H.;
Smith, Henry I.; Schattenburg, M. L.; Woodgate, B. E.; Jordan, S.
Bibcode: 1992aiaa.confQ....C
Altcode:
The general design and performance characteristics of MIT's two
dispersive spectrometers, the Bragg Crystal Spectrometer (BCS) and
the High Energy Transmission Grating Spectrometer (HETG), now being
developed for the Advanced X-ray Astrophysics Facility (AXAF), are
described. Particular attention is given to the development of the
critical technologies incorporated into these instruments, including
BCS diffractors, imaging gas flow proportional counters, and grating
elements for the HETG. The principal stages and the current status of
the developments are reviewed.
Title: Formation of the HE II 304 Line in the Solar Atmosphere
Authors: Jordan, S. D.
Bibcode: 1991BAAS...23.1387J
Altcode:
No abstract at ADS
Title: Solar Chromospheric Heating
Authors: Jordan, S. D.
Bibcode: 1991BAAS...23.1037J
Altcode:
No abstract at ADS
Title: Magneto-optical effects from free electrons in magnetic
white dwarfs.
Authors: Jordan, S.; O'Connell, R. F.; Koester, D.
Bibcode: 1991A&A...242..206J
Altcode:
When calculating synthetic spectra and theoretical values for the
polarization of magnetic white dwarfs, it is important to take the
magnetooptical effects arising from free electrons into account. The
hitherto used formalism of Pacholczyk (1976) breaks down at fields
higher than 100 MG where the cyclotron resonance occurs in the optical
region of the electromagnetic spectrum. In a new program for the
analysis of magnetic white dwarfs a consistent approach is used that
allows for damping by electron collisions. Inaccuracies originating
from the discrete division of the stellar disk into a limited number
of surface elements are reduced by taking into account the variation
of the magnetic field over the individual elements.
Title: The stellar component of the Hamburg Schmidt Survey
Authors: Heber, U.; Jordan, S.; Weidemann, V.
Bibcode: 1991ASIC..336..109H
Altcode: 1991whdw.conf..109H
No abstract at ADS
Title: White dwarfs in the Hamburg Schmidt Survey
Authors: Jordan, S.; Heber, U.; Weidemann, V.
Bibcode: 1991ASIC..336..121J
Altcode: 1991whdw.conf..121J
No abstract at ADS
Title: Cyclotron and Zeeman spectroscopy of the AM Herculis binary
V834 Cen.
Authors: Beuermann, K.; Schwope, A. D.; Thomas, H. -C.; Jordan, S.
Bibcode: 1990AGAb....4...44B
Altcode:
No abstract at ADS
Title: Cyclotron and Zeeman spectroscopy of V834 Cen.
Authors: Beuermann, K.; Schwope, A. D.; Thomas, H. -C.; Jordan, S.
Bibcode: 1990apcb.conf..265B
Altcode: 1990cvlm.proc..265B
No abstract at ADS
Title: Discovery of two bright low-redshift quasars by the Hamburg
quasar survey.
Authors: Groote, D.; Heber, U.; Jordan, S.
Bibcode: 1989A&A...223L...1G
Altcode:
Two bright low-redshift quasars, HS 0624+6907 (V = 14.2^m^, z = 0.370)
and HS 1227+4530 (V = 16.3^m^, z = 0.194) have been discovered by
follow-up spectroscopy of candidates selected from objective prism
plates of the Hamburg Schmidt sky survey. Accordingly, HS 0624+6907 is
the brightest quasar discovered by optical selection. Its spectrum and
absolute magnitude (M = -28.0^m^) closely resemble those of 3C273 except
for the presence of very narrow O III-emission lines. HS 1227+4530 is
less luminous (M = -24.0^m^). We discuss the possibility that some
bright low-redshift quasars have escaped detection because their
objective-prism spectra are similar to those of subluminous F stars.
Title: SUMER - Solar ultraviolet measurements of emitted radiation.
Authors: Curdt, W.; Wilhelm, K.; Axford, W. I.; Marsch, E.; Richter,
A. K.; Gabriel, A. H.; Lemaire, P.; Vial, J. -C.; Grewing, M.; Huber,
M. C. E.; Jordan, S. D.; Poland, A. I.; Thomas, R. J.; Timothy, J. G.
Bibcode: 1989AGAb....2...14C
Altcode: 1989amt..conf...14C
No abstract at ADS
Title: The stellar component of the Hamburg-Schmidt survey.
Authors: Heber, U.; Jordan, S.; Weidemann, V.
Bibcode: 1989AGAb....3...92H
Altcode: 1989AGAb....3...94H
No abstract at ADS
Title: FGK stars and T Tauri stars
Authors: Cram, Lawrence E.; Kuhi, Leonard V.; Jordan, Stuart; Thomas,
Richard; Goldberg, Leo; Pecker, Jean-Claude
Bibcode: 1989NASSP.502.....C
Altcode: 1989QB843.C6C73....; 1989fstt.book.....C
The purpose of this book, FGK Stars and T Tauri Stars, like all other
volumes of this series, is to exhibit and describe the best space
data and ground based data currently available, and also to describe
and critically evaluate the status of current theoretical models
and physical mechanisms that have been proposed to interpret these
data. The method for obtaining this book was to collect manuscripts
from competent volunteer authors, and then to collate and edit these
contributions to form a well structured book, which will be distributed
to an international community of research astronomers by NASA and by
the French CNRS.
Title: Very Hot DA White Dwarfs From the Hamburg-Quasar Survey
Authors: Jordan, S.
Bibcode: 1989iue..prop.3564J
Altcode:
No abstract at ADS
Title: Introduction to Helio- and Astro- Seismology
Authors: Jordan, Stuart
Bibcode: 1988ASSL..148..157J
Altcode: 1988pmls.conf..157J
No abstract at ADS
Title: O stars and Wolf-Rayet stars
Authors: Conti, Peter S.; Underhill, Anne B.; Jordan, Stuart; Thomas,
Richard N.; Goldberg, Leo; Pecker, Jean-Claude; Baade, D.; Divan,
L.; Garmany, C. D.; Henrichs, H. F.; Kudritzki, R. P.; Pauldrach,
A.; Prévot-Burnichon, M. -L.; Puls, J.
Bibcode: 1988NASSP.497.....C
Altcode: 1988oswr.book.....C
Basic information is given about O and Wolf-Rayet stars indicating
how these stars are defined and what their chief observable properties
are. Part 2 of the volume discussed four related themes pertaining to
the hottest and most luminous stars. Presented are: an observational
overview of the spectroscopic classification and extrinsic properties
of O and Wolf-Rayet stars; the intrinsic parameters of luminosity,
effective temperature, mass, and composition of the stars, and a
discussion of their viability; stellar wind properties; and the
related issues concerning the efforts of stellar radiation and
wind on the immediate interstellar environment are presented. Contents: Perspective (R. N. Thomas).Part I. Introduction (L. Divan,
M.-L. Prévot-Burnichon).1. Introducing the O and Wolf-Rayet stars.Part
II. One perspective on O, Of, and Wolf-Rayet stars emphasizing winds
and mass loss, with remarks on environment and evolution:2. Overview of
O, Of, and Wolf-Rayet populations (P. S. Conti). 3. Intrinsic stellar
parameters (P. S. Conti, D. Baade). 4. Stellar winds: (a) Introduction
(P. S. Conti). (b) Mass loss from O stars (C. D. Garmany). (c) Mass
loss in Wolf-Rayetstars (P. S. Conti). (d) Radiation-driven winds
of hot luminous stars (R. P. Kudritzki, A. Pauldrach, J. Puls). (e)
Intrinsic variability in ultraviolet spectra of early-type stars: the
discrete absorption lines (H. Henrichs). 5. Environments and evolution
(P. S. Conti).Part III. Another perspective on O, Of, and Wolf-Rayet
stars, emphasizing model atmospheres and possibilities for atmospheric
heating (A. B. Underhill): 6. Understanding the O and Wolf-Rayet
stars. 7. Model Atmospheres and the theory of spectra for O and
Wolf-Rayet stars. 8. The physics of the mantles of hot stars. 9. Summary
of processes influencing the spectra of O and Wolf-Rayet stars.
Title: EUV photometry of DA white dwarfs with EXOSAT.
Authors: Jordan, S.; Koester, D.; Wulf-Mathies, C.; Brunner, H.
Bibcode: 1987A&A...185..253J
Altcode:
The authors present EXOSAT EUV observations for 9 white dwarfs of
spectral type DA. These are analysed together with other observational
data from the literature using theoretical model atmospheres. For
8 objects He/H abundance ratios and interstellar hydrogen column
densities are obtained. The data for HZ 43 seem to contradict recent
results of other authors; possible explanations for the discrepancies
are discussed. The results show that higher He/H ratios as well as
a larger range of observed values are found in the hotter objects
with Teff > 50,000K, whereas the cooler objects
(Teff < 45,000K) have remarkably similar He/H ratios.
Title: Model atmospheres and synthetic spectra for white dwarfs with
chemically stratified atmospheres.
Authors: Jordan, S.; Koester, D.
Bibcode: 1986A&AS...65..367J
Altcode:
White dwarfs showing He and H features in their spectrum have almost
exclusively been interpreted in terms of chemically homogeneous
atmospheres with widely varying H/He ratios. In view of the
extremely short diffusion time scales an alternative explanation
might be a thin H layer on top of a He shell with a transition region
as determined from diffusion equilibrium. In this paper the authors
report results of model atmospheres and synthetic spectra calculations
for such models. Temperature structure and emerging spectral fluxes
are discussed, with emphasis on the EUV range where a number of hot
white dwarfs has been observed in the past and more data are collected
presently by EXOSAT.
Title: The M-type stars
Authors: Johnson, Hollis Ralph; Querci, Francois R.; Jordan, Stuart;
Thomas, Richard; Goldberg, Leo; Pecker, Jean-Claude
Bibcode: 1986NASSP.492.....J
Altcode: 1986mts..book.....J; 1986QB843.M16M89...
No abstract at ADS
Title: Science with the Solar Optical Telescope (SOT).
Authors: Jordan, S. D.
Bibcode: 1984ESASP.220..165J
Altcode: 1984ESPM....4..165J
The Solar Optical Telescope (SOT) will provide the necessary data for
attacking several fundamental problems in the energetics and dynamics
of the solar atmosphere, including the origin and evolution of the
Sun's magnetic field, the structure of solar subsurface convection, the
heating of the outer solar atmosphere, and sources of the solar wind
in the lower lying regions of the outer atmosphere. This telescope,
of a Gregorian configuration, will have 1.3-meter-diameter primary
mirror that will be capable of achieving close to 0.1-arc-second angular
resolution on the Sun in both visible and ultraviolet wavelengths. This
paper gives further details on the telescope and how it will be operated
in space to achieve the scientific objectives.
Title: Book-Review - the Sun as a Star
Authors: Jordan, S.; Collier, A. C.
Bibcode: 1984Obs...104...43J
Altcode:
No abstract at ADS
Title: The solar optical telescope
Authors: Hogan, G. D.; Jordan, S. D.
Bibcode: 1984aiaa.meetQ....H
Altcode:
This paper describes NASA's Solar Optical Telescope (SOT), which is
designed to measure the density temperature, magnetic fields, and
the nonthermal velocity fields of solar features on a scale at which
the basic physical processes are occurring. A series of 7- to 14-day
missions carrying a 1.3-meter solar-observing telescope that has a
spatial resolution only slightly larger than the photon mean-free-path
of about 80 km will be flown as a Spacelab-attached payload aboard the
Space Transportation System (STS) in mid-1990. The telescope (Fig. 1)
will be built and integrated by the Perkin-Elmer Corporation and is
managed by NASA's Goddard Space Flight Center. Coarse pointing to the
sun is provided by the Spacelab instrument pointing system (IPS),
whereas fine pointing is provided by the Observatory pointing and
control system. The science instruments for the first mission, the
photometric filtergraph and the coordinated filtergraph/spectrograph,
that are integrated into a combined instrument package are also
described.
Title: Two cosmic-ray detectors with high charge and energy resolution
in the GeV/nucleon range.
Authors: Dwyer, R.; Jordan, S.; Meyer, P.
Bibcode: 1984NIMPA.224..247D
Altcode:
No abstract at ADS
Title: The Sun as a Star
Authors: Jordan, S.; Rosner, R.
Bibcode: 1983Natur.303...92J
Altcode:
No abstract at ADS
Title: The Solar Optical Telescope Facility
Authors: Yellin, M.; Fisher, R.; Jordan, S.
Bibcode: 1983BAAS...15..709Y
Altcode:
No abstract at ADS
Title: Book-Review - the Sun as a Star
Authors: Jordan, S.
Bibcode: 1983Natur.301..449J
Altcode:
No abstract at ADS
Title: Book-Review - the Sun as a Star
Authors: Jordan, S. D.
Bibcode: 1982JBAA...92..290J
Altcode:
No abstract at ADS
Title: Solar-stellar astrophysics
Authors: Jordan, S. D.
Bibcode: 1982ComAp...9..211J
Altcode:
Nonthermal physical processes in the solar atmosphere are discussed. The
solar atmospheric regions are defined, and solar convection and
its phenomena are explained. The relationship of the solar dynamo,
magnetic field, and flares is explored. The solar atmospheric velocity
fields are discussed, and the unresolved problem of the nature of
atmospheric heating is detailed. The solar wind heating and acceleration
are discussed and the need for global solar atmospheric models is
emphasized. The application of these solar nonthermal processes to
the stars in general is then taken up, employing the same categories
as were applied to the solar atmosphere.
Title: Book-Review - the Sun as a Star
Authors: Jordan, S.; Hearn, A. G.
Bibcode: 1982SSRv...32..465J
Altcode:
No abstract at ADS
Title: Summary: The Sun
Authors: Jordan, S. D.
Bibcode: 1982obvf.conf..445J
Altcode:
No abstract at ADS
Title: Book-Review - the Sun as a Star
Authors: Jordan, S.; Mihalas, D.
Bibcode: 1982S&T....63..262J
Altcode:
No abstract at ADS
Title: The Solar Optical Telescope = SOT
Authors: Jordan, S. D.
Bibcode: 1981SSRv...29..333J
Altcode:
The Solar Optical Telescope (SOT), which NASA plans to operate on
Spacelab, should provide resolution down to 0.1 arc sec, thus offering
the capability for solving a number of fundamental problems in solar
magnetism and in atmospheric heating and dynamics.
Title: Book-Review - the Sun as a Star / NASA-SP-450
Authors: Jordan, S.
Bibcode: 1981Sci...214.1268J
Altcode:
No abstract at ADS
Title: The sun as a star
Authors: Jordan, Stuart
Bibcode: 1981NASSP.450.....J
Altcode: 1981suas.nasa.....J
No abstract at ADS
Title: Chromospheric heating.
Authors: Jordan, S. D.
Bibcode: 1981NASSP.450..301J
Altcode: 1981suas.nasa..301J
General features of the solar chromospheric heating problem, which also
apply to many stellar chromospheres, are reviewed. Current theories
are discussed, including: heating by short period sound waves; the
weak shock theory; and the time-dependent approach.
Title: Book-Review - the Sun as a Star
Authors: Jordan, S.
Bibcode: 1981S&T....62..592J
Altcode:
No abstract at ADS
Title: The solar modulation of cosmic ray electrons 1969-1977
Authors: Evenson, P.; Caldwell, J.; Jordan, S.; Meyer, P.
Bibcode: 1979JGR....84.5361E
Altcode:
We discuss the gross morphological features of the cosmic ray electron
spectrum from 200 MeV to 6 GeV as measured in eight of the nine years
1969-1977. We find no evidence that the solar magnetic field polarity
change of 1970-1971 affected the relative modulation of electrons and
protons. However, previously noted problems in explaining the variation
of both the electron and proton modulation by one model can at least
qualitatively be understood by allowing simultaneous variations in
the diffusion coefficient and the boundary of the modulation region in
a spherically symmetric solution of the Fokker-Planck equation. This
model also predicts a change in the radial gradient of protons from
1973 to 1974.
Title: The Cosmic Ray Electron Spectra in 1974 and 1975 and the
Implications for Solar Modulation
Authors: Caldwell, J. H.; Evenson, P.; Jordan, S.; Meyer, P.
Bibcode: 1977ICRC...11..203C
Altcode: 1977ICRC...15k.203C
No abstract at ADS
Title: The Cosmic-Ray Electron Spectra in 1974 and 1975 and the
Implications for Solar Modulation (Abstract)
Authors: Caldwell, J. H.; Evenson, P.; Jordan, S.; Meyer, P.
Bibcode: 1977ICRC....3..205C
Altcode: 1977ICRC...15c.205C
No abstract at ADS
Title: Physical processes determining the chromospheric temperature
distribution.
Authors: Jordan, S. D.
Bibcode: 1977SoPh...51...51J
Altcode:
Calculations performed with several models of the solar chromosphere
support Ulmschneider's conclusion that relatively short period
acoustic waves heat the low chromosphere in the region just above the
temperature minimum. However, these same short period waves (10⩽
period P⩽80 s) are not able to maintain chromospheric temperatures
at heights where τ5000Å(normal) < 10-6. The
calculations also show that an earlier conjecture stating that the
H2 population might influence the non-LTE chromospheric
H- population is probably not correct, due to lower values
of the ratio ne/nH inferred from more recent
observations. Finally, the calculations support Athay's contention that
the Cayrel mechanism alone cannot produce the observed temperature
rise, because the magnitude of the radiative cooling in the lines is
too great.
Title: The Cosmic Ray Electron Spectrum in 1973 and 1974
Authors: Caldwell, J.; Evenson, P.; Jordan, S.; Meyer, P.
Bibcode: 1975ICRC....3.1000C
Altcode: 1975ICRC...14.1000C
No abstract at ADS
Title: 1.0 Arc Second Structure on the Sun at 3.71 cm Wavelength
Authors: Hobbs, Robert W.; Jordan, Stuart D.; Webster, William J.,
Jr.; Maran, Stephen P.; Caulk, Howard M.
Bibcode: 1974SoPh...36..369H
Altcode:
No abstract at ADS
Title: Can the Dissipation of High Frequency Sound Waves in the Low
Chromosphere Produce the Temperature Rise?
Authors: Jordan, S. D.
Bibcode: 1974BAAS....6R.289J
Altcode:
No abstract at ADS
Title: Small-Scale Structure in Solar Flaring Regions Observed at
Wavelengths of 3.71 and 11.1 cm
Authors: Hobbs, R. W.; Jordan, S. D.; Maran, S. P.; Caulk, H. M.;
Webster, W. J., Jr.
Bibcode: 1973ApL....15..193H
Altcode: 1974ApL....15..193H
No abstract at ADS
Title: Further Aspects of Weak Shock Theory Applied to the Solar
Chromosphere
Authors: Jordan, Stuart D.
Bibcode: 1973SoPh...30..327J
Altcode:
The low chromosphere now seems definitely to require mechanical heating,
and dissipation of initially acoustic waves by shocking is one of the
most promising possibilities. Results of recent calculations indicate
that the weak shock theory may be applicable here, but discrepancies
exist among various applications of this theory, and the explanations
offered to date are not completely satisfactory. It is shown here that
the different approximations used by different authors to evaluate the
mechanical flux integral play an important role in producing these
discrepancies, in addition to the already well known effects of the
density scale heights and the wave periods. Arguments are presented
favoring Ulmschneider's method for evaluation of this flux integral.
Title: High Resolution Radio Observations of the Sun at 3.71 and
11.1 cm
Authors: Hobbs, Robert W.; Jordan, Stuart D.; Webster, William J.
Bibcode: 1973NPhS..243...48H
Altcode: 1973Natur.243...48H
ON January 14, 1972, observations of the Sun were made at 3.71 and 11.1
cm, using the NRAO three-element interferometer in the 2.7-1.8-0.9 km
configuration. At 3.71 and 11.1 cm the minimum fringe spacings are 2.8
and 8.5 arc s, respectively, and the corresponding primary half-power
beam widths are 6 and 18 arc min. The existing system was desensitized
by turning off the r-f parametric amplifiers. This resulted in a system
noise temperature of about 1,200 K. Because these preliminary results
represent only six hours of observing time, it was not possible to
determine the source positions precisely.
Title: High resolution observations of a solar active region at 3.71
and 11.1 cm wavelength.
Authors: Hobbs, R. W.; Jordan, S. D.; Maran, S. P.; Webster, W. J., Jr.
Bibcode: 1973BAAS....5Q.284H
Altcode:
No abstract at ADS
Title: "mechanical Heating in Stellar Chromospheres Using the Sun
as a Test CASE,"
Authors: Jordan, Stuart D.
Bibcode: 1973NASSP.317..181J
Altcode: 1973stch.coll..181J; 1973IAUCo..19..181J
No abstract at ADS
Title: Stellar Chromospheres
Authors: Jordan, S. D.; Avrett, Eugene H.
Bibcode: 1973NASSP.317.....J
Altcode: 1973IAUCo..19.....J; 1973stch.coll.....J
No abstract at ADS
Title: High resolution measurements of the sun at 3.71 and 11.1
cm wavelength.
Authors: Hobbs, R. W.; Jordan, S. D.; Webster, W. J., Jr.
Bibcode: 1972BAAS....4..322H
Altcode:
No abstract at ADS
Title: High Resolution Measurements of the Sun at 3.71 and 11.1
cm Wavelength.
Authors: Hobbs, R. W.; Jordan, S. D.; Webster, W. J., Jr.
Bibcode: 1972BAAS....4R.310H
Altcode:
No abstract at ADS
Title: Evidence for the 300-SECOND Oscillation from OSO-7
Extreme-Ultraviolet Observations
Authors: Chapman, Robert D.; Jordan, Stuart D.; Neupert, Werner M.;
Thomas, Roger J.
Bibcode: 1972ApJ...174L..97C
Altcode:
Evidence is presented for a 300-second oscillation in the intensity
of solar extreme-ultraviolet emission lines of He U, Mg viii, and Mg
Ix as observed by OSO-7.
Title: A New Slant on Discrepancies Given by Weak Shock Theory in
the Solar Chromosphere.
Authors: Jordan, S. D.
Bibcode: 1971BAAS....3..462J
Altcode:
No abstract at ADS
Title: Estimates of the role of mechanical heating in the low solar
chromosphere.
Authors: Jordan, S. D.
Bibcode: 1971BAAS....3R.262J
Altcode:
No abstract at ADS
Title: The Effect of the Density Scale Height on Shock-Wave Heating
in the Low Solar Chromosphere
Authors: Jordan, Stuart
Bibcode: 1970ApJ...161.1189J
Altcode:
The heating of the low solar chromosphere by the shock dissipation
of weak hydromagnetic waves was estimated by Osterbrock, who used
the van de Hulst model for the low chromosphere. A feature of this
model is values for the density scale heights of the order of 200
km. More recent models have scale heights with values generally less
than this. When one repeats the solution of Osterbrock's equations
for these new models in the case of negligible magnetic fields (of
the order of 1 gauss), the resulting shock strength grows so rapidly
that the range of applicability of the weak-shock theory is extremely
limited. In the case of stronger magnetic fields, other complications
arise and the problem cannot be treated in this simple way. The results
tend to support the picture of a very rapid transition from the low
chromosphere to tbe corona in regions of weak magnetic-field strength.
Title: Some Comments on Shock-Wave Heating of the Low Solar
Chromosphere
Authors: Jordan, Stuart D.
Bibcode: 1970BAAS....2..202J
Altcode:
No abstract at ADS
Title: The Heating of the Chromosphere
Authors: Jordan, Stuart
Bibcode: 1970NASSP.251..111J
Altcode:
No abstract at ADS
Title: Recent advances in solar physics.
Authors: Maran, S. P.; Jordan, S. D.
Bibcode: 1970EExSc...1...73M
Altcode:
No abstract at ADS
Title: Why the Temperature Rise does not Occur in Radiative
Equilibrium in Stellar Chromospheres of Dominant H^{-} Opacity
Authors: Jordan, S. D.
Bibcode: 1969ApJ...157..465J
Altcode:
It is demonstrated that the temperature inversion in the low solar
chromosphere is very unlikely to result from the influence of
the photospheric radiation field on the low-density gas Therefore,
dissipation of mechanical energy is necessary to produce the rise. Since
this effect follows directly from the dominance of the continuum
opacity by the H ion, the same conclusion follows for all stellar
chromospheres where H- dominates the continuum opacity
Title: Why the Temperature Rise Does Not Occur in Radiative
Equilibrium in Low Solar Chromosphere
Authors: Jordan, Stuart D.
Bibcode: 1969BAAS....1..282J
Altcode:
No abstract at ADS
Title: The Temperature Structure and Energy Balance in the Solar
Chromosphere.
Authors: Jordan, Stuart Davis
Bibcode: 1968PhDT.........2J
Altcode:
No abstract at ADS
Title: Energy Balance and Temperature Structure in the Solar
Chromosphere.
Authors: Jordan, Stuart
Bibcode: 1968AJS....73R.186J
Altcode:
Application of a method developed by the author for calculating
the temperature structure in a shock-heated atmosphere is made
to the solar chromosphere in the regions of the Mg II resonance
doublet formation. The ionization of magnesium, the amount of
mechanical energy required to maintain a temperature plateau, and
the general applicability of weak shock theory to this problem are
discussed. Comparison of results with observations is offered. The
main conclusion is that complete single ionization of magnesium
over a spherically symmetrical region of 500 km thickness in the
low chromosphere just above the H- region seems to require more
mechanical energy than either (1) the weak shock theory yields or (2)
is observed as a net radiative loss in the emission cores of the Mg
II doublet. Thus, to preserve reasonable physical conditions in the
Mg II producing region, with a temperature in the range 6000~8000G,
departures from spherical symmetry are required. This is consistent
with spectroheliograms taken in Mg II.