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Author name code: appourchaux
ADS astronomy entries on 2022-09-14
author:"Appourchaux, Thierry" 

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Title: Solar-like oscillations and ellipsoidal variations in TESS
    observations of the binary 12 Boötis
Authors: Ball, Warrick H.; Miglio, Andrea; Chaplin, William J.;
   Stassun, Keivan G.; García, Rafael; González-Cuesta, Lucia; Mathur,
   Savita; Appourchaux, Thierry; Benomar, Othman; Buzasi, Derek L.;
   Jiang, Chen; Kayhan, Cenk; Örtel, Sibel; Orhan, Zeynep Çelik;
   Yıldız, Mutlu; Ong, J. M. Joel; Basu, Sarbani
2022MNRAS.tmp.2121B    Altcode: 2022arXiv220802302B
  Binary stars in which oscillations can be studied in either or both
  components can provide powerful constraints on our understanding
  of stellar physics. The bright binary 12 Boötis (12 Boo) is a
  particularly promising system because the primary is roughly 60 per
  cent brighter than the secondary despite being only a few per cent
  more massive. Both stars have substantial surface convection zones
  and are therefore, presumably, solar-like oscillators. We report
  here the first detection of solar-like oscillations and ellipsoidal
  variations in the TESS light curve of 12 Boo. Though the solar-like
  oscillations are not clear enough to unambiguously measure individual
  mode frequencies, we combine global asteroseismic parameters and a
  precise fit to the spectral energy distribution (SED) to provide new
  constraints on the properties of the system that are several times more
  precise than values in the literature. The SED fit alone provides new
  effective temperatures, luminosities and radii of 6115 ± 45 K, 7.531
  ± 0.110 L<SUB>⊙</SUB> and 2.450 ± 0.045 R<SUB>⊙</SUB> for 12 Boo
  A and 6200 ± 60 K, 4.692 ± 0.095 L<SUB>⊙</SUB> and 1.901 ± 0.045
  R<SUB>⊙</SUB> for 12 Boo B. When combined with our asteroseismic
  constraints on 12 Boo A, we obtain an age of $2.67^{+0.12}_{-0.16}\,
  \mathrm{Gyr}$, which is consistent with that of 12 Boo B.

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Title: The on-ground data reduction and calibration pipeline for
    SO/PHI-HRT
Authors: Sinjan, J.; Calchetti, D.; Hirzberger, J.; Orozco Suárez,
   D.; Albert, K.; Albelo Jorge, N.; Appourchaux, T.; Alvarez-Herrero,
   A.; Blanco Rodríguez, J.; Gandorfer, A.; Germerott, D.; Guerrero,
   L.; Gutierrez Marquez, P.; Kahil, F.; Kolleck, M.; Solanki, S. K.; del
   Toro Iniesta, J. C.; Volkmer, R.; Woch, J.; Fiethe, B.; Gómez Cama,
   J. M.; Pérez-Grande, I.; Sanchis Kilders, E.; Balaguer Jiménez,
   M.; Bellot Rubio, L. R.; Carmona, M.; Deutsch, W.; Fernandez-Rico,
   G.; Fernández-Medina, A.; García Parejo, P.; Gasent Blesa, J. L.;
   Gizon, L.; Grauf, B.; Heerlein, K.; Korpi-Lagg, A.; Lange, T.; López
   Jiménez, A.; Maue, T.; Meller, R.; Michalik, H.; Moreno Vacas, A.;
   Müller, R.; Nakai, E.; Schmidt, W.; Schou, J.; Schühle, U.; Staub,
   J.; Strecker, H.; Torralbo, I.; Valori, G.
2022arXiv220814904S    Altcode:
  The ESA/NASA Solar Orbiter space mission has been successfully launched
  in February 2020. Onboard is the Polarimetric and Helioseismic Imager
  (SO/PHI), which has two telescopes, a High Resolution Telescope
  (HRT) and the Full Disc Telescope (FDT). The instrument is designed
  to infer the photospheric magnetic field and line-of-sight velocity
  through differential imaging of the polarised light emitted by the
  Sun. It calculates the full Stokes vector at 6 wavelength positions
  at the Fe I 617.3 nm absorption line. Due to telemetry constraints,
  the instrument nominally processes these Stokes profiles onboard,
  however when telemetry is available, the raw images are downlinked and
  reduced on ground. Here the architecture of the on-ground pipeline
  for HRT is presented, which also offers additional corrections not
  currently available on board the instrument. The pipeline can reduce
  raw images to the full Stokes vector with a polarimetric sensitivity
  of $10^{-3}\cdot I_{c}$ or better.

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Title: The magnetic drivers of campfires seen by the Polarimetric
    and Helioseismic Imager (PHI) on Solar Orbiter
Authors: Kahil, F.; Hirzberger, J.; Solanki, S. K.; Chitta, L. P.;
   Peter, H.; Auchère, F.; Sinjan, J.; Orozco Suárez, D.; Albert,
   K.; Albelo Jorge, N.; Appourchaux, T.; Alvarez-Herrero, A.; Blanco
   Rodríguez, J.; Gandorfer, A.; Germerott, D.; Guerrero, L.; Gutiérrez
   Márquez, P.; Kolleck, M.; del Toro Iniesta, J. C.; Volkmer, R.;
   Woch, J.; Fiethe, B.; Gómez Cama, J. M.; Pérez-Grande, I.; Sanchis
   Kilders, E.; Balaguer Jiménez, M.; Bellot Rubio, L. R.; Calchetti,
   D.; Carmona, M.; Deutsch, W.; Fernández-Rico, G.; Fernández-Medina,
   A.; García Parejo, P.; Gasent-Blesa, J. L.; Gizon, L.; Grauf, B.;
   Heerlein, K.; Lagg, A.; Lange, T.; López Jiménez, A.; Maue, T.;
   Meller, R.; Michalik, H.; Moreno Vacas, A.; Müller, R.; Nakai,
   E.; Schmidt, W.; Schou, J.; Schühle, U.; Staub, J.; Strecker, H.;
   Torralbo, I.; Valori, G.; Aznar Cuadrado, R.; Teriaca, L.; Berghmans,
   D.; Verbeeck, C.; Kraaikamp, E.; Gissot, S.
2022A&A...660A.143K    Altcode: 2022arXiv220213859K
  Context. The Extreme Ultraviolet Imager (EUI) on board the Solar Orbiter
  (SO) spacecraft observed small extreme ultraviolet (EUV) bursts,
  termed campfires, that have been proposed to be brightenings near the
  apexes of low-lying loops in the quiet-Sun atmosphere. The underlying
  magnetic processes driving these campfires are not understood. <BR
  /> Aims: During the cruise phase of SO and at a distance of 0.523
  AU from the Sun, the Polarimetric and Helioseismic Imager on Solar
  Orbiter (SO/PHI) observed a quiet-Sun region jointly with SO/EUI,
  offering the possibility to investigate the surface magnetic field
  dynamics underlying campfires at a spatial resolution of about 380
  km. <BR /> Methods: We used co-spatial and co-temporal data of the
  quiet-Sun network at disc centre acquired with the High Resolution
  Imager of SO/EUI at 17.4 nm (HRI<SUB>EUV</SUB>, cadence 2 s) and the
  High Resolution Telescope of SO/PHI at 617.3 nm (HRT, cadence 2.5
  min). Campfires that are within the SO/PHI−SO/EUI common field
  of view were isolated and categorised according to the underlying
  magnetic activity. <BR /> Results: In 71% of the 38 isolated events,
  campfires are confined between bipolar magnetic features, which seem to
  exhibit signatures of magnetic flux cancellation. The flux cancellation
  occurs either between the two main footpoints, or between one of the
  footpoints of the loop housing the campfire and a nearby opposite
  polarity patch. In one particularly clear-cut case, we detected the
  emergence of a small-scale magnetic loop in the internetwork followed
  soon afterwards by a campfire brightening adjacent to the location
  of the linear polarisation signal in the photosphere, that is to
  say near where the apex of the emerging loop lays. The rest of the
  events were observed over small scattered magnetic features, which
  could not be identified as magnetic footpoints of the campfire hosting
  loops. <BR /> Conclusions: The majority of campfires could be driven
  by magnetic reconnection triggered at the footpoints, similar to the
  physical processes occurring in the burst-like EUV events discussed
  in the literature. About a quarter of all analysed campfires, however,
  are not associated to such magnetic activity in the photosphere, which
  implies that other heating mechanisms are energising these small-scale
  EUV brightenings.

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Title: PLATO Performance
Authors: Cabrera, J.; Rauer, H.; Börner, A.; Grießbach, D.; Paproth,
   C.; Samadi, R.; Appourchaux, T.
2021plat.confE..95C    Altcode:
  The PLATO mission (PLAnetary Transits and Oscillations of stars,
  hereafter abbreviated as PLATO) has been selected as part of ESA's
  Cosmic Vision 2015-2025 program for the M3 mission launch foreseen
  in 2026. The main science goal of PLATO is to detect and characterize
  extrasolar planets, including terrestrial planets in the habitable zone
  (HZ) of their host stars. Characterization here means to derive accurate
  planetary radii, masses, and ages. In order to achieve these goals,
  it is mandatory to characterize the host stars. As transit search
  is an indirect detection and characterization method, the accurate
  knowledge of the host star parameters limits the accuracy of the derived
  planet parameters. PLATO will therefore monitor hundreds of thousands
  of stars for up to three years in order to fully characterize stars
  with asteroseismology and to detect transiting planets. The resulting
  large data set of stellar light curves provides an additional science
  return of the mission that reaches far beyond the exoplanet science
  case into stellar, Galactic, and extragalactic research. <P />PLATO
  Payload features a multi-telescope configuration consisting of 26
  cameras, of 12 cm pupil size aperture each, covering a field of view of
  about 2000 square degrees spread over 104 CCDs of 20 million pixels a
  piece. PLATO has strict noise requirements achieved through excellent
  optics transmission and quantum efficiency, low read-out noise, and
  stringent pointing requirements. <P />In this talk we will review the
  drivers for PLATO Performance and present the most recent description
  of the status of noise budget and verification of main performance
  requirements (including field of view and pointing performance).

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Title: A journey of exploration to the polar regions of a star:
    probing the solar poles and the heliosphere from high helio-latitude
Authors: Harra, Louise; Andretta, Vincenzo; Appourchaux, Thierry;
   Baudin, Frédéric; Bellot-Rubio, Luis; Birch, Aaron C.; Boumier,
   Patrick; Cameron, Robert H.; Carlsson, Matts; Corbard, Thierry;
   Davies, Jackie; Fazakerley, Andrew; Fineschi, Silvano; Finsterle,
   Wolfgang; Gizon, Laurent; Harrison, Richard; Hassler, Donald M.;
   Leibacher, John; Liewer, Paulett; Macdonald, Malcolm; Maksimovic,
   Milan; Murphy, Neil; Naletto, Giampiero; Nigro, Giuseppina; Owen,
   Christopher; Martínez-Pillet, Valentín; Rochus, Pierre; Romoli,
   Marco; Sekii, Takashi; Spadaro, Daniele; Veronig, Astrid; Schmutz, W.
2021ExA...tmp...93H    Altcode: 2021arXiv210410876H
  A mission to view the solar poles from high helio-latitudes (above 60°)
  will build on the experience of Solar Orbiter as well as a long heritage
  of successful solar missions and instrumentation (e.g. SOHO Domingo et
  al. (Solar Phys. 162(1-2), 1-37 1995), STEREO Howard et al. (Space
  Sci. Rev. 136(1-4), 67-115 2008), Hinode Kosugi et al. (Solar
  Phys. 243(1), 3-17 2007), Pesnell et al. Solar Phys. 275(1-2),
  3-15 2012), but will focus for the first time on the solar poles,
  enabling scientific investigations that cannot be done by any other
  mission. One of the major mysteries of the Sun is the solar cycle. The
  activity cycle of the Sun drives the structure and behaviour of the
  heliosphere and of course, the driver of space weather. In addition,
  solar activity and variability provides fluctuating input into the
  Earth climate models, and these same physical processes are applicable
  to stellar systems hosting exoplanets. One of the main obstructions
  to understanding the solar cycle, and hence all solar activity,
  is our current lack of understanding of the polar regions. In this
  White Paper, submitted to the European Space Agency in response to the
  Voyage 2050 call, we describe a mission concept that aims to address
  this fundamental issue. In parallel, we recognise that viewing the Sun
  from above the polar regions enables further scientific advantages,
  beyond those related to the solar cycle, such as unique and powerful
  studies of coronal mass ejection processes, from a global perspective,
  and studies of coronal structure and activity in polar regions. Not
  only will these provide important scientific advances for fundamental
  stellar physics research, they will feed into our understanding of
  impacts on the Earth and other planets' space environment.

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Title: Amplitude of solar gravity modes generated by penetrative
    plumes
Authors: Pinçon, C.; Appourchaux, T.; Buldgen, G.
2021A&A...650A..47P    Altcode: 2021arXiv210303760P
  Context. The observation of gravity modes is expected to give us
  unprecedented insights into the inner dynamics of the Sun. Nevertheless,
  there is currently no consensus on their detection. Within this
  framework, predicting their amplitudes is essential to guide future
  observational strategies and seismic studies. <BR /> Aims: While
  previous estimates considered convective turbulent eddies as the
  driving mechanism, our aim is to predict the amplitude of low-frequency
  asymptotic gravity modes generated by penetrative convection at the top
  of the radiative zone. <BR /> Methods: A generation model previously
  developed for progressive gravity waves was adapted to the case of
  resonant gravity modes. The stellar oscillation equations were analyzed
  considering the plume ram pressure at the top of the radiative zone as
  the forcing term. The plume velocity field was modeled in an analytical
  form. <BR /> Results: We obtain an analytical expression for the mode
  energy. It is found to depend critically on the time evolution of the
  plumes inside the generation region. Using a solar model, we then
  compute the apparent surface radial velocity of low-degree gravity
  modes as would be measured by the GOLF instrument, in the frequency
  range 10 µHz ≤ ν ≤ 100 µHz. In the case of a Gaussian plume
  time evolution, gravity modes turn out to be undetectable because of
  too small surface amplitudes. This holds true despite a wide range
  of values considered for the parameters of the model. In the other
  limiting case of an exponential time evolution, plumes are expected
  to drive gravity modes in a much more efficient way because of a much
  higher temporal coupling between the plumes and the modes than in the
  Gaussian case. Using reasonable values for the plume parameters based
  on semi-analytical models, the apparent surface velocities in this
  case are one order of magnitude lower than the 22-year GOLF detection
  threshold and lower than the previous estimates considering turbulent
  pressure as the driving mechanism, with a maximum value of 0.05 cm
  s<SUP>−1</SUP> for ℓ = 1 and ν ≈ 100 µHz. When accounting
  for uncertainties on the plume parameters, the apparent surface
  velocities in the most favorable plausible case become comparable to
  those predicted with turbulent pressure, and the GOLF observation time
  required for a detection at ν ≈ 100 µHz and ℓ = 1 is reduced
  to about 50 yr. <BR /> Conclusions: Penetrative convection can drive
  gravity modes in the most favorable plausible case as efficiently
  as turbulent pressure, with amplitudes slightly below the current
  detection threshold. When detected in the future, the measurement
  of their amplitudes is expected to provide information on the plume
  dynamics at the base of the convective zone. In order to make a proper
  interpretation, this potential nevertheless requires further theoretical
  improvements in our description of penetrative plumes.

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Title: Characteristics and performances of an interferometric Doppler
    imager installed at the 188 cm telescope of Okayama Observatory
Authors: Schmider, François-Xavier; Dejonghe, Julien; Guillot,
   Tristan; Ikoma, Masahiro; Boumier, Patrick; Sato, Bun'ei; Jackiewicz,
   Jason; Izumiura, Hideyuki; Hanayama, Hidekazu; Abe, Lyu; Gonçalves,
   Ivan; Gouvret, Carole; Fantéï-Caujolle, Yan; Morand, Frédéric;
   Preis, Olivier; Rivet, Jean-Pierre; Appourchaux, Thierry; Leclec'h,
   Jean-Christophe; Ballans, Hervé; Langlet, François; Baudin,
   Frédéric; Aoyama, Yuhiko; Kawaushi, Kiyoe; Horiuchi, Takashi;
   Gaulme, Patrick; Voelz, David; Underwood, Thomas
2020SPIE11447E..3DS    Altcode:
  We describe the performances of a novel Doppler imager, aimed to
  detect acoustic oscillations and atmospheric dynamics at the surface of
  giant planets of the Solar System in the frame of the JOVIAL (Jovian
  Oscillations detection by Velocity Imaging At several Longitudes)
  project. The first JOVIAL instrument was installed on the 188cm
  telescope at Okayama branch of National Astronomical Observatory of
  Japan (NAOJ) in April 2019. This instrument is a part of a ground based
  network of three identical instruments installed on telescopes around
  the world for continuous observations. First observations of Jupiter
  with the JOVIAL instrument were achieved in June 2019. We describe the
  instrument principle, its design and the set-up at Okayama observatory,
  as well as the performances reached during the first observing run. We
  finally provide plans for future observations with the network.

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Title: A Journey of Exploration to the Polar Regions of a Star:
    Probing the Solar Poles and the Heliosphere from High Helio-Latitude
Authors: Finsterle, W.; Harra, L.; Andretta, V.; Appourchaux, T.;
   Baudin, F.; Bellot Rubio, L.; Birch, A.; Boumier, P.; Cameron, R. H.;
   Carlsson, M.; Corbard, T.; Davies, J. A.; Fazakerley, A. N.; Fineschi,
   S.; Gizon, L. C.; Harrison, R. A.; Hassler, D.; Leibacher, J. W.;
   Liewer, P. C.; Macdonald, M.; Maksimovic, M.; Murphy, N.; Naletto, G.;
   Nigro, G.; Owen, C. J.; Martinez-Pillet, V.; Rochus, P. L.; Romoli,
   M.; Sekii, T.; Spadaro, D.; Veronig, A.
2020AGUFMSH0110005F    Altcode:
  A mission to view the solar poles from high helio-latitudes (above
  60°) will build on the experience of Solar Orbiter as well as a long
  heritage of successful solar missions and instrumentation (e.g. SOHO,
  STEREO, Hinode, SDO), but will focus for the first time on the solar
  poles, enabling scientific investigations that cannot be done by
  any other mission. One of the major mysteries of the Sun is the solar
  cycle. The activity cycle of the Sun drives the structure and behaviour
  of the heliosphere and is, of course, the driver of space weather. In
  addition, solar activity and variability provides fluctuating input
  into the Earth climate models, and these same physical processes
  are applicable to stellar systems hosting exoplanets. One of the
  main obstructions to understanding the solar cycle, and hence all
  solar activity, is our current lack of understanding of the polar
  regions. We describe a mission concept that aims to address this
  fundamental issue. In parallel, we recognise that viewing the Sun
  from above the polar regions enables further scientific advantages,
  beyond those related to the solar cycle, such as unique and powerful
  studies of coronal mass ejection processes, from a global perspective,
  and studies of coronal structure and activity in polar regions. Not
  only will these provide important scientific advances for fundamental
  stellar physics research, they will feed into our understanding of
  impacts on the Earth and other planets' space environment.

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Title: The Solar Orbiter Science Activity Plan. Translating solar
    and heliospheric physics questions into action
Authors: Zouganelis, I.; De Groof, A.; Walsh, A. P.; Williams, D. R.;
   Müller, D.; St Cyr, O. C.; Auchère, F.; Berghmans, D.; Fludra,
   A.; Horbury, T. S.; Howard, R. A.; Krucker, S.; Maksimovic, M.;
   Owen, C. J.; Rodríguez-Pacheco, J.; Romoli, M.; Solanki, S. K.;
   Watson, C.; Sanchez, L.; Lefort, J.; Osuna, P.; Gilbert, H. R.;
   Nieves-Chinchilla, T.; Abbo, L.; Alexandrova, O.; Anastasiadis, A.;
   Andretta, V.; Antonucci, E.; Appourchaux, T.; Aran, A.; Arge, C. N.;
   Aulanier, G.; Baker, D.; Bale, S. D.; Battaglia, M.; Bellot Rubio,
   L.; Bemporad, A.; Berthomier, M.; Bocchialini, K.; Bonnin, X.; Brun,
   A. S.; Bruno, R.; Buchlin, E.; Büchner, J.; Bucik, R.; Carcaboso,
   F.; Carr, R.; Carrasco-Blázquez, I.; Cecconi, B.; Cernuda Cangas, I.;
   Chen, C. H. K.; Chitta, L. P.; Chust, T.; Dalmasse, K.; D'Amicis, R.;
   Da Deppo, V.; De Marco, R.; Dolei, S.; Dolla, L.; Dudok de Wit, T.;
   van Driel-Gesztelyi, L.; Eastwood, J. P.; Espinosa Lara, F.; Etesi,
   L.; Fedorov, A.; Félix-Redondo, F.; Fineschi, S.; Fleck, B.; Fontaine,
   D.; Fox, N. J.; Gandorfer, A.; Génot, V.; Georgoulis, M. K.; Gissot,
   S.; Giunta, A.; Gizon, L.; Gómez-Herrero, R.; Gontikakis, C.; Graham,
   G.; Green, L.; Grundy, T.; Haberreiter, M.; Harra, L. K.; Hassler,
   D. M.; Hirzberger, J.; Ho, G. C.; Hurford, G.; Innes, D.; Issautier,
   K.; James, A. W.; Janitzek, N.; Janvier, M.; Jeffrey, N.; Jenkins,
   J.; Khotyaintsev, Y.; Klein, K. -L.; Kontar, E. P.; Kontogiannis,
   I.; Krafft, C.; Krasnoselskikh, V.; Kretzschmar, M.; Labrosse, N.;
   Lagg, A.; Landini, F.; Lavraud, B.; Leon, I.; Lepri, S. T.; Lewis,
   G. R.; Liewer, P.; Linker, J.; Livi, S.; Long, D. M.; Louarn, P.;
   Malandraki, O.; Maloney, S.; Martinez-Pillet, V.; Martinovic, M.;
   Masson, A.; Matthews, S.; Matteini, L.; Meyer-Vernet, N.; Moraitis,
   K.; Morton, R. J.; Musset, S.; Nicolaou, G.; Nindos, A.; O'Brien,
   H.; Orozco Suarez, D.; Owens, M.; Pancrazzi, M.; Papaioannou, A.;
   Parenti, S.; Pariat, E.; Patsourakos, S.; Perrone, D.; Peter, H.;
   Pinto, R. F.; Plainaki, C.; Plettemeier, D.; Plunkett, S. P.; Raines,
   J. M.; Raouafi, N.; Reid, H.; Retino, A.; Rezeau, L.; Rochus, P.;
   Rodriguez, L.; Rodriguez-Garcia, L.; Roth, M.; Rouillard, A. P.;
   Sahraoui, F.; Sasso, C.; Schou, J.; Schühle, U.; Sorriso-Valvo, L.;
   Soucek, J.; Spadaro, D.; Stangalini, M.; Stansby, D.; Steller, M.;
   Strugarek, A.; Štverák, Š.; Susino, R.; Telloni, D.; Terasa, C.;
   Teriaca, L.; Toledo-Redondo, S.; del Toro Iniesta, J. C.; Tsiropoula,
   G.; Tsounis, A.; Tziotziou, K.; Valentini, F.; Vaivads, A.; Vecchio,
   A.; Velli, M.; Verbeeck, C.; Verdini, A.; Verscharen, D.; Vilmer, N.;
   Vourlidas, A.; Wicks, R.; Wimmer-Schweingruber, R. F.; Wiegelmann,
   T.; Young, P. R.; Zhukov, A. N.
2020A&A...642A...3Z    Altcode: 2020arXiv200910772Z
  Solar Orbiter is the first space mission observing the solar plasma
  both in situ and remotely, from a close distance, in and out of the
  ecliptic. The ultimate goal is to understand how the Sun produces
  and controls the heliosphere, filling the Solar System and driving
  the planetary environments. With six remote-sensing and four in-situ
  instrument suites, the coordination and planning of the operations are
  essential to address the following four top-level science questions:
  (1) What drives the solar wind and where does the coronal magnetic field
  originate?; (2) How do solar transients drive heliospheric variability?;
  (3) How do solar eruptions produce energetic particle radiation that
  fills the heliosphere?; (4) How does the solar dynamo work and drive
  connections between the Sun and the heliosphere? Maximising the
  mission's science return requires considering the characteristics
  of each orbit, including the relative position of the spacecraft
  to Earth (affecting downlink rates), trajectory events (such
  as gravitational assist manoeuvres), and the phase of the solar
  activity cycle. Furthermore, since each orbit's science telemetry
  will be downloaded over the course of the following orbit, science
  operations must be planned at mission level, rather than at the level
  of individual orbits. It is important to explore the way in which those
  science questions are translated into an actual plan of observations
  that fits into the mission, thus ensuring that no opportunities are
  missed. First, the overarching goals are broken down into specific,
  answerable questions along with the required observations and the
  so-called Science Activity Plan (SAP) is developed to achieve this. The
  SAP groups objectives that require similar observations into Solar
  Orbiter Observing Plans, resulting in a strategic, top-level view of
  the optimal opportunities for science observations during the mission
  lifetime. This allows for all four mission goals to be addressed. In
  this paper, we introduce Solar Orbiter's SAP through a series of
  examples and the strategy being followed.

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Title: The Polarimetric and Helioseismic Imager on Solar Orbiter
Authors: Solanki, S. K.; del Toro Iniesta, J. C.; Woch, J.; Gandorfer,
   A.; Hirzberger, J.; Alvarez-Herrero, A.; Appourchaux, T.; Martínez
   Pillet, V.; Pérez-Grande, I.; Sanchis Kilders, E.; Schmidt, W.;
   Gómez Cama, J. M.; Michalik, H.; Deutsch, W.; Fernandez-Rico, G.;
   Grauf, B.; Gizon, L.; Heerlein, K.; Kolleck, M.; Lagg, A.; Meller, R.;
   Müller, R.; Schühle, U.; Staub, J.; Albert, K.; Alvarez Copano, M.;
   Beckmann, U.; Bischoff, J.; Busse, D.; Enge, R.; Frahm, S.; Germerott,
   D.; Guerrero, L.; Löptien, B.; Meierdierks, T.; Oberdorfer, D.;
   Papagiannaki, I.; Ramanath, S.; Schou, J.; Werner, S.; Yang, D.;
   Zerr, A.; Bergmann, M.; Bochmann, J.; Heinrichs, J.; Meyer, S.;
   Monecke, M.; Müller, M. -F.; Sperling, M.; Álvarez García, D.;
   Aparicio, B.; Balaguer Jiménez, M.; Bellot Rubio, L. R.; Cobos
   Carracosa, J. P.; Girela, F.; Hernández Expósito, D.; Herranz, M.;
   Labrousse, P.; López Jiménez, A.; Orozco Suárez, D.; Ramos, J. L.;
   Barandiarán, J.; Bastide, L.; Campuzano, C.; Cebollero, M.; Dávila,
   B.; Fernández-Medina, A.; García Parejo, P.; Garranzo-García, D.;
   Laguna, H.; Martín, J. A.; Navarro, R.; Núñez Peral, A.; Royo, M.;
   Sánchez, A.; Silva-López, M.; Vera, I.; Villanueva, J.; Fourmond,
   J. -J.; de Galarreta, C. Ruiz; Bouzit, M.; Hervier, V.; Le Clec'h,
   J. C.; Szwec, N.; Chaigneau, M.; Buttice, V.; Dominguez-Tagle, C.;
   Philippon, A.; Boumier, P.; Le Cocguen, R.; Baranjuk, G.; Bell,
   A.; Berkefeld, Th.; Baumgartner, J.; Heidecke, F.; Maue, T.; Nakai,
   E.; Scheiffelen, T.; Sigwarth, M.; Soltau, D.; Volkmer, R.; Blanco
   Rodríguez, J.; Domingo, V.; Ferreres Sabater, A.; Gasent Blesa,
   J. L.; Rodríguez Martínez, P.; Osorno Caudel, D.; Bosch, J.; Casas,
   A.; Carmona, M.; Herms, A.; Roma, D.; Alonso, G.; Gómez-Sanjuan, A.;
   Piqueras, J.; Torralbo, I.; Fiethe, B.; Guan, Y.; Lange, T.; Michel,
   H.; Bonet, J. A.; Fahmy, S.; Müller, D.; Zouganelis, I.
2020A&A...642A..11S    Altcode: 2019arXiv190311061S
  <BR /> Aims: This paper describes the Polarimetric and Helioseismic
  Imager on the Solar Orbiter mission (SO/PHI), the first magnetograph and
  helioseismology instrument to observe the Sun from outside the Sun-Earth
  line. It is the key instrument meant to address the top-level science
  question: How does the solar dynamo work and drive connections between
  the Sun and the heliosphere? SO/PHI will also play an important role
  in answering the other top-level science questions of Solar Orbiter,
  while hosting the potential of a rich return in further science. <BR
  /> Methods: SO/PHI measures the Zeeman effect and the Doppler shift
  in the Fe I 617.3 nm spectral line. To this end, the instrument
  carries out narrow-band imaging spectro-polarimetry using a tunable
  LiNbO<SUB>3</SUB> Fabry-Perot etalon, while the polarisation modulation
  is done with liquid crystal variable retarders. The line and the nearby
  continuum are sampled at six wavelength points and the data are recorded
  by a 2k × 2k CMOS detector. To save valuable telemetry, the raw data
  are reduced on board, including being inverted under the assumption of
  a Milne-Eddington atmosphere, although simpler reduction methods are
  also available on board. SO/PHI is composed of two telescopes; one,
  the Full Disc Telescope, covers the full solar disc at all phases of
  the orbit, while the other, the High Resolution Telescope, can resolve
  structures as small as 200 km on the Sun at closest perihelion. The high
  heat load generated through proximity to the Sun is greatly reduced by
  the multilayer-coated entrance windows to the two telescopes that allow
  less than 4% of the total sunlight to enter the instrument, most of
  it in a narrow wavelength band around the chosen spectral line. <BR />
  Results: SO/PHI was designed and built by a consortium having partners
  in Germany, Spain, and France. The flight model was delivered to
  Airbus Defence and Space, Stevenage, and successfully integrated into
  the Solar Orbiter spacecraft. A number of innovations were introduced
  compared with earlier space-based spectropolarimeters, thus allowing
  SO/PHI to fit into the tight mass, volume, power and telemetry budgets
  provided by the Solar Orbiter spacecraft and to meet the (e.g. thermal)
  challenges posed by the mission's highly elliptical orbit.

---------------------------------------------------------
Title: The Solar Orbiter SPICE instrument. An extreme UV imaging
    spectrometer
Authors: SPICE Consortium; Anderson, M.; Appourchaux, T.; Auchère, F.;
   Aznar Cuadrado, R.; Barbay, J.; Baudin, F.; Beardsley, S.; Bocchialini,
   K.; Borgo, B.; Bruzzi, D.; Buchlin, E.; Burton, G.; Büchel, V.;
   Caldwell, M.; Caminade, S.; Carlsson, M.; Curdt, W.; Davenne, J.;
   Davila, J.; Deforest, C. E.; Del Zanna, G.; Drummond, D.; Dubau,
   J.; Dumesnil, C.; Dunn, G.; Eccleston, P.; Fludra, A.; Fredvik, T.;
   Gabriel, A.; Giunta, A.; Gottwald, A.; Griffin, D.; Grundy, T.; Guest,
   S.; Gyo, M.; Haberreiter, M.; Hansteen, V.; Harrison, R.; Hassler,
   D. M.; Haugan, S. V. H.; Howe, C.; Janvier, M.; Klein, R.; Koller,
   S.; Kucera, T. A.; Kouliche, D.; Marsch, E.; Marshall, A.; Marshall,
   G.; Matthews, S. A.; McQuirk, C.; Meining, S.; Mercier, C.; Morris,
   N.; Morse, T.; Munro, G.; Parenti, S.; Pastor-Santos, C.; Peter, H.;
   Pfiffner, D.; Phelan, P.; Philippon, A.; Richards, A.; Rogers, K.;
   Sawyer, C.; Schlatter, P.; Schmutz, W.; Schühle, U.; Shaughnessy,
   B.; Sidher, S.; Solanki, S. K.; Speight, R.; Spescha, M.; Szwec, N.;
   Tamiatto, C.; Teriaca, L.; Thompson, W.; Tosh, I.; Tustain, S.; Vial,
   J. -C.; Walls, B.; Waltham, N.; Wimmer-Schweingruber, R.; Woodward,
   S.; Young, P.; de Groof, A.; Pacros, A.; Williams, D.; Müller, D.
2020A&A...642A..14S    Altcode: 2019arXiv190901183A; 2019arXiv190901183S
  <BR /> Aims: The Spectral Imaging of the Coronal Environment (SPICE)
  instrument is a high-resolution imaging spectrometer operating at
  extreme ultraviolet wavelengths. In this paper, we present the concept,
  design, and pre-launch performance of this facility instrument on the
  ESA/NASA Solar Orbiter mission. <BR /> Methods: The goal of this paper
  is to give prospective users a better understanding of the possible
  types of observations, the data acquisition, and the sources that
  contribute to the instrument's signal. <BR /> Results: The paper
  discusses the science objectives, with a focus on the SPICE-specific
  aspects, before presenting the instrument's design, including optical,
  mechanical, thermal, and electronics aspects. This is followed by a
  characterisation and calibration of the instrument's performance. The
  paper concludes with descriptions of the operations concept and data
  processing. <BR /> Conclusions: The performance measurements of the
  various instrument parameters meet the requirements derived from the
  mission's science objectives. The SPICE instrument is ready to perform
  measurements that will provide vital contributions to the scientific
  success of the Solar Orbiter mission.

---------------------------------------------------------
Title: On attempting to automate the identification of mixed dipole
    modes for subgiant stars
Authors: Appourchaux, T.
2020A&A...642A.226A    Altcode: 2020arXiv200810973A
  Context. The existence of mixed modes in stars is a marker of stellar
  evolution. Their detection serves for a better determination of
  stellar age. <BR /> Aims: The goal of this paper is to identify the
  dipole modes in an automatic manner without human intervention. <BR
  /> Methods: I used the power spectra obtained by the Kepler mission
  for the application of the method. I computed asymptotic dipole mode
  frequencies as a function of the coupling factor and dipole period
  spacing, as well as other parameters. For each star, I collapsed the
  power in an echelle diagramme aligned onto the monopole and dipole
  mixed modes. The power at the null frequency was used as a figure
  of merit. Using a genetic algorithm, I then optimised the figure of
  merit by adjusting the location of the dipole frequencies in the power
  spectrum. Using published frequencies, I compared the asymptotic dipole
  mode frequencies with published frequencies. I also used published
  frequencies to derive the coupling factor and dipole period spacing
  using a non-linear least squares fit. I used Monte-Carlo simulations
  of the non-linear least square fit to derive error bars for each
  parameter. <BR /> Results: From the 44 subgiants studied, the automatic
  identification allows one to retrieve within 3 μHz, at least 80% of
  the modes for 32 stars, and within 6 μHz, at least 90% of the modes
  for 37 stars. The optimised and fitted gravity-mode period spacing and
  coupling factor are in agreement with previous measurements. Random
  errors for the mixed-mode parameters deduced from the Monte-Carlo
  simulation are about 30-50 times smaller than previously determined
  errors, which are in fact systematic errors. <BR /> Conclusions: The
  period spacing and coupling factors of mixed modes in subgiants are
  confirmed. The current automated procedure will need to be improved upon
  using a more accurate asymptotic model and/or proper statistical tests.

---------------------------------------------------------
Title: The Solar Orbiter EUI instrument: The Extreme Ultraviolet
    Imager
Authors: Rochus, P.; Auchère, F.; Berghmans, D.; Harra, L.; Schmutz,
   W.; Schühle, U.; Addison, P.; Appourchaux, T.; Aznar Cuadrado,
   R.; Baker, D.; Barbay, J.; Bates, D.; BenMoussa, A.; Bergmann, M.;
   Beurthe, C.; Borgo, B.; Bonte, K.; Bouzit, M.; Bradley, L.; Büchel,
   V.; Buchlin, E.; Büchner, J.; Cabé, F.; Cadiergues, L.; Chaigneau,
   M.; Chares, B.; Choque Cortez, C.; Coker, P.; Condamin, M.; Coumar,
   S.; Curdt, W.; Cutler, J.; Davies, D.; Davison, G.; Defise, J. -M.;
   Del Zanna, G.; Delmotte, F.; Delouille, V.; Dolla, L.; Dumesnil, C.;
   Dürig, F.; Enge, R.; François, S.; Fourmond, J. -J.; Gillis, J. -M.;
   Giordanengo, B.; Gissot, S.; Green, L. M.; Guerreiro, N.; Guilbaud,
   A.; Gyo, M.; Haberreiter, M.; Hafiz, A.; Hailey, M.; Halain, J. -P.;
   Hansotte, J.; Hecquet, C.; Heerlein, K.; Hellin, M. -L.; Hemsley, S.;
   Hermans, A.; Hervier, V.; Hochedez, J. -F.; Houbrechts, Y.; Ihsan,
   K.; Jacques, L.; Jérôme, A.; Jones, J.; Kahle, M.; Kennedy, T.;
   Klaproth, M.; Kolleck, M.; Koller, S.; Kotsialos, E.; Kraaikamp, E.;
   Langer, P.; Lawrenson, A.; Le Clech', J. -C.; Lenaerts, C.; Liebecq,
   S.; Linder, D.; Long, D. M.; Mampaey, B.; Markiewicz-Innes, D.;
   Marquet, B.; Marsch, E.; Matthews, S.; Mazy, E.; Mazzoli, A.; Meining,
   S.; Meltchakov, E.; Mercier, R.; Meyer, S.; Monecke, M.; Monfort,
   F.; Morinaud, G.; Moron, F.; Mountney, L.; Müller, R.; Nicula, B.;
   Parenti, S.; Peter, H.; Pfiffner, D.; Philippon, A.; Phillips, I.;
   Plesseria, J. -Y.; Pylyser, E.; Rabecki, F.; Ravet-Krill, M. -F.;
   Rebellato, J.; Renotte, E.; Rodriguez, L.; Roose, S.; Rosin, J.;
   Rossi, L.; Roth, P.; Rouesnel, F.; Roulliay, M.; Rousseau, A.; Ruane,
   K.; Scanlan, J.; Schlatter, P.; Seaton, D. B.; Silliman, K.; Smit,
   S.; Smith, P. J.; Solanki, S. K.; Spescha, M.; Spencer, A.; Stegen,
   K.; Stockman, Y.; Szwec, N.; Tamiatto, C.; Tandy, J.; Teriaca, L.;
   Theobald, C.; Tychon, I.; van Driel-Gesztelyi, L.; Verbeeck, C.;
   Vial, J. -C.; Werner, S.; West, M. J.; Westwood, D.; Wiegelmann, T.;
   Willis, G.; Winter, B.; Zerr, A.; Zhang, X.; Zhukov, A. N.
2020A&A...642A...8R    Altcode:
  Context. The Extreme Ultraviolet Imager (EUI) is part of the remote
  sensing instrument package of the ESA/NASA Solar Orbiter mission
  that will explore the inner heliosphere and observe the Sun from
  vantage points close to the Sun and out of the ecliptic. Solar Orbiter
  will advance the "connection science" between solar activity and the
  heliosphere. <BR /> Aims: With EUI we aim to improve our understanding
  of the structure and dynamics of the solar atmosphere, globally as well
  as at high resolution, and from high solar latitude perspectives. <BR />
  Methods: The EUI consists of three telescopes, the Full Sun Imager and
  two High Resolution Imagers, which are optimised to image in Lyman-α
  and EUV (17.4 nm, 30.4 nm) to provide a coverage from chromosphere
  up to corona. The EUI is designed to cope with the strong constraints
  imposed by the Solar Orbiter mission characteristics. Limited telemetry
  availability is compensated by state-of-the-art image compression,
  onboard image processing, and event selection. The imposed power
  limitations and potentially harsh radiation environment necessitate
  the use of novel CMOS sensors. As the unobstructed field of view of
  the telescopes needs to protrude through the spacecraft's heat shield,
  the apertures have been kept as small as possible, without compromising
  optical performance. This led to a systematic effort to optimise the
  throughput of every optical element and the reduction of noise levels
  in the sensor. <BR /> Results: In this paper we review the design
  of the two elements of the EUI instrument: the Optical Bench System
  and the Common Electronic Box. Particular attention is also given to
  the onboard software, the intended operations, the ground software,
  and the foreseen data products. <BR /> Conclusions: The EUI will
  bring unique science opportunities thanks to its specific design,
  its viewpoint, and to the planned synergies with the other Solar
  Orbiter instruments. In particular, we highlight science opportunities
  brought by the out-of-ecliptic vantage point of the solar poles,
  the high-resolution imaging of the high chromosphere and corona,
  and the connection to the outer corona as observed by coronagraphs.

---------------------------------------------------------
Title: The Evolution of Rotation and Magnetic Activity in 94 Aqr Aa
    from Asteroseismology with TESS
Authors: Metcalfe, Travis S.; van Saders, Jennifer L.; Basu, Sarbani;
   Buzasi, Derek; Chaplin, William J.; Egeland, Ricky; Garcia, Rafael
   A.; Gaulme, Patrick; Huber, Daniel; Reinhold, Timo; Schunker, Hannah;
   Stassun, Keivan G.; Appourchaux, Thierry; Ball, Warrick H.; Bedding,
   Timothy R.; Deheuvels, Sébastien; González-Cuesta, Lucía; Handberg,
   Rasmus; Jiménez, Antonio; Kjeldsen, Hans; Li, Tanda; Lund, Mikkel N.;
   Mathur, Savita; Mosser, Benoit; Nielsen, Martin B.; Noll, Anthony;
   Çelik Orhan, Zeynep; Örtel, Sibel; Santos, Ângela R. G.; Yildiz,
   Mutlu; Baliunas, Sallie; Soon, Willie
2020ApJ...900..154M    Altcode: 2020arXiv200712755M
  Most previous efforts to calibrate how rotation and magnetic activity
  depend on stellar age and mass have relied on observations of clusters,
  where isochrones from stellar evolution models are used to determine the
  properties of the ensemble. Asteroseismology employs similar models to
  measure the properties of an individual star by matching its normal
  modes of oscillation, yielding the stellar age and mass with high
  precision. We use 27 days of photometry from the Transiting Exoplanet
  Survey Satellite to characterize solar-like oscillations in the G8
  subgiant of the 94 Aqr triple system. The resulting stellar properties,
  when combined with a reanalysis of 35 yr of activity measurements
  from the Mount Wilson HK project, allow us to probe the evolution of
  rotation and magnetic activity in the system. The asteroseismic age
  of the subgiant agrees with a stellar isochrone fit, but the rotation
  period is much shorter than expected from standard models of angular
  momentum evolution. We conclude that weakened magnetic braking may be
  needed to reproduce the stellar properties, and that evolved subgiants
  in the hydrogen shell-burning phase can reinvigorate large-scale dynamo
  action and briefly sustain magnetic activity cycles before ascending
  the red giant branch.

---------------------------------------------------------
Title: The Solaris Solar Polar Mission
Authors: Hassler, Donald M.; Newmark, Jeff; Gibson, Sarah; Harra,
   Louise; Appourchaux, Thierry; Auchere, Frederic; Berghmans, David;
   Colaninno, Robin; Fineschi, Silvano; Gizon, Laurent; Gosain, Sanjay;
   Hoeksema, Todd; Kintziger, Christian; Linker, John; Rochus, Pierre;
   Schou, Jesper; Viall, Nicholeen; West, Matt; Woods, Tom; Wuelser,
   Jean-Pierre
2020EGUGA..2217703H    Altcode:
  The solar poles are one of the last unexplored regions of the solar
  system. Although Ulysses flew over the poles in the 1990s, it did
  not have remote sensing instruments onboard to probe the Sun's polar
  magnetic field or surface/sub-surface flows.We will discuss Solaris,
  a proposed Solar Polar MIDEX mission to revolutionize our understanding
  of the Sun by addressing fundamental questions that can only be answered
  from a polar vantage point. Solaris uses a Jupiter gravity assist to
  escape the ecliptic plane and fly over both poles of the Sun to &gt;75
  deg. inclination, obtaining the first high-latitude, multi-month-long,
  continuous remote-sensing solar observations. Solaris will address key
  outstanding, breakthrough problems in solar physics and fill holes in
  our scientific understanding that will not be addressed by current
  missions.With focused science and a simple, elegant mission design,
  Solaris will also provide enabling observations for space weather
  research (e.g. polar view of CMEs), and stimulate future research
  through new unanticipated discoveries.

---------------------------------------------------------
Title: Age dating of an early Milky Way merger via asteroseismology
    of the naked-eye star ν Indi
Authors: Chaplin, William J.; Serenelli, Aldo M.; Miglio, Andrea;
   Morel, Thierry; Mackereth, J. Ted; Vincenzo, Fiorenzo; Kjeldsen, Hans;
   Basu, Sarbani; Ball, Warrick H.; Stokholm, Amalie; Verma, Kuldeep;
   Mosumgaard, Jakob Rørsted; Silva Aguirre, Victor; Mazumdar, Anwesh;
   Ranadive, Pritesh; Antia, H. M.; Lebreton, Yveline; Ong, Joel;
   Appourchaux, Thierry; Bedding, Timothy R.; Christensen-Dalsgaard,
   Jørgen; Creevey, Orlagh; García, Rafael A.; Handberg, Rasmus; Huber,
   Daniel; Kawaler, Steven D.; Lund, Mikkel N.; Metcalfe, Travis S.;
   Stassun, Keivan G.; Bazot, Michäel; Beck, Paul G.; Bell, Keaton J.;
   Bergemann, Maria; Buzasi, Derek L.; Benomar, Othman; Bossini, Diego;
   Bugnet, Lisa; Campante, Tiago L.; Orhan, Zeynep çelik; Corsaro,
   Enrico; González-Cuesta, Lucía; Davies, Guy R.; Di Mauro, Maria
   Pia; Egeland, Ricky; Elsworth, Yvonne P.; Gaulme, Patrick; Ghasemi,
   Hamed; Guo, Zhao; Hall, Oliver J.; Hasanzadeh, Amir; Hekker, Saskia;
   Howe, Rachel; Jenkins, Jon M.; Jiménez, Antonio; Kiefer, René;
   Kuszlewicz, James S.; Kallinger, Thomas; Latham, David W.; Lundkvist,
   Mia S.; Mathur, Savita; Montalbán, Josefina; Mosser, Benoit; Bedón,
   Andres Moya; Nielsen, Martin Bo; Örtel, Sibel; Rendle, Ben M.; Ricker,
   George R.; Rodrigues, Thaíse S.; Roxburgh, Ian W.; Safari, Hossein;
   Schofield, Mathew; Seager, Sara; Smalley, Barry; Stello, Dennis;
   Szabó, Róbert; Tayar, Jamie; Themeßl, Nathalie; Thomas, Alexandra
   E. L.; Vanderspek, Roland K.; van Rossem, Walter E.; Vrard, Mathieu;
   Weiss, Achim; White, Timothy R.; Winn, Joshua N.; Yıldız, Mutlu
2020NatAs...4..382C    Altcode: 2020NatAs.tmp....7C; 2020arXiv200104653C
  Over the course of its history, the Milky Way has ingested multiple
  smaller satellite galaxies<SUP>1</SUP>. Although these accreted
  stellar populations can be forensically identified as kinematically
  distinct structures within the Galaxy, it is difficult in general
  to date precisely the age at which any one merger occurred. Recent
  results have revealed a population of stars that were accreted via the
  collision of a dwarf galaxy, called Gaia-Enceladus<SUP>1</SUP>, leading
  to substantial pollution of the chemical and dynamical properties of
  the Milky Way. Here we identify the very bright, naked-eye star ν
  Indi as an indicator of the age of the early in situ population of
  the Galaxy. We combine asteroseismic, spectroscopic, astrometric and
  kinematic observations to show that this metal-poor, alpha-element-rich
  star was an indigenous member of the halo, and we measure its age
  to be 11.0 ±0.7 ? (stat) ±0.8 ? (sys) billion years. The star
  bears hallmarks consistent with having been kinematically heated by
  the Gaia-Enceladus collision. Its age implies that the earliest the
  merger could have begun was 11.6 and 13.2 billion years ago, at 68%
  and 95% confidence, respectively. Computations based on hierarchical
  cosmological models slightly reduce the above limits.

---------------------------------------------------------
Title: Jupiter atmospheric dynamics from ground-based Doppler imaging
Authors: Schmider, François-Xavier; Guillot, Tristan; Gonçalves,
   Ivan; Jackiewicz, Jason; Underwood, Thomas; Voelz, David; Gaulme,
   Patrick; Boumier, Patrick; Appourchaux, Thierry; Morales-Juberias,
   Raùl; Ikoma, Masahiro; Sato, Bun'ei; Izumiura, Hideyuki
2019EPSC...13.1613S    Altcode:
  We present velocity maps of Jupiter obtained from the ground with a
  dedicated Doppler imaging spectrograph. It demonstrates the potential
  of this method to study the motion in the atmosphere of gaseous
  planets. It proves to be complementary to cloud-tracking to understand
  the atmospheric dynamics

---------------------------------------------------------
Title: VizieR Online Data Catalog: High-precision radial velocities
    for HD 221416 (Huber+, 2019)
Authors: Huber, D.; Chaplin, W. J.; Chontos, A.; Kjeldsen, H.;
   Christensen-Dalsgaard, J.; Bedding, T. R.; Ball, W.; Brahm, R.;
   Espinoza, N.; Henning, T.; Jordan, A.; Sarkis, P.; Knudstrup, E.;
   Albrecht, S.; Grundahl, F.; Andersen, M. F.; Palle, P. L.; Crossfield,
   I.; Fulton, B.; Howard, A. W.; Isaacson, H. T.; Weiss, L. M.; Handberg,
   R.; Lund, M. N.; Serenelli, A. M.; Rorsted Mosumgaard, J.; Stokholm,
   A.; Bieryla, A.; Buchhave, L. A.; Latham, D. W.; Quinn, S. N.;
   Gaidos, E.; Hirano, T.; Ricker, G. R.; Vanderspek, R. K.; Seager,
   S.; Jenkins, J. M.; Winn, J. N.; Antia, H. M.; Appourchaux, T.; Basu,
   S.; Bell, K. J.; Benomar, O.; Bonanno, A.; Buzasi, D. L.; Campante,
   T. L.; Celik Orhan, Z.; Corsaro, E.; Cunha, M. S.; Davies, G. R.;
   Deheuvels, S.; Grunblatt, S. K.; Hasanzadeh, A.; di Mauro, M. P.;
   Garcia, R. A.; Gaulme, P.; Girardi, L.; Guzik, J. A.; Hon, M.; Jiang,
   C.; Kallinger, T.; Kawaler, S. D.; Kuszlewicz, J. S.; Lebreton, Y.; Li,
   T.; Lucas, M.; Lundkvist, M. S.; Mann, A. W.; Mathis, S.; Mathur, S.;
   Mazumdar, A.; Metcalfe, T. S.; Miglio, A.; Monteiro, M. J. P. F. G.;
   Mosser, B.; Noll, A.; Nsamba, B.; Ong, J. M. J.; Ortel, S.; Pereira,
   F.; Ranadive, P.; Regulo, C.; Rodrigues, T. S.; Roxburgh, I. W.;
   Aguirre, V. S.; Smalley, B.; Schofield, M.; Sousa, S. G.; Stassun,
   K. G.; Stello, D.; Tayar, J.; White, T. R.; Verma, K.; Vrard, M.;
   Yildiz, M.; Baker, D.; Bazot, M.; Beichmann, C.; Bergmann, C.;
   Bugnet, L.; Cale, B.; Carlino, R.; Cartwright, S. M.; Christiansen,
   J. L.; Ciardi, D. R.; Creevey, O.; Dittmann, J. A.; Do Nascimento,
   J. -D., Jr.; van Eylen, V.; Furesz, G.; Gagne, J.; Gao, P.; Gazeas,
   K.; Giddens, F.; Hall, O. J.; Hekker, S.; Ireland, M. J.; Latouf,
   N.; Lebrun, D.; Levine, A. M.; Matzko, W.; Natinsky, E.; Page, E.;
   Plavchan, P.; Mansouri-Samani, M.; McCauliff, S.; Mullally, S. E.;
   Orenstein, B.; Soto, A. G.; Paegert, M.; van Saders, J. L.; Schnaible,
   C.; Soderblom, D. R.; Szabo, R.; Tanner, A.; Tinney, C. G.; Teske,
   J.; Thomas, A.; Trampedach, R.; Wright, D.; Yuan, T. T.; Zohrabi, F.
2019yCat..51570245H    Altcode:
  We obtained high-resolution spectra of HD 221416 using several
  facilities within the TESS Follow-up Observation Program (TFOP),
  including HIRES (Vogt et al. 1994SPIE.2198..362V) on the 10 m telescope
  at Keck Observatory (Maunakea, Hawai'i); the Hertzsprung SONG Telescope
  at Teide Observatory (Tenerife; Grundahl et al. 2017ApJ...836..142G);
  HARPS (Mayor et al. 2003Msngr.114...20M), FEROS (Kaufer et
  al. 1999Msngr..95....8K), Coralie (Queloz et al. 2001Msngr.105....1Q),
  and FIDEOS (Vanzi et al. 2018MNRAS.477.5041V) on the MPG/ESO 3.6 m, 2.2
  m, 1.2 m, and 1 m telescopes at La Silla Observatory (Chile); Veloce
  (Gilbert et al. 2018SPIE10702E..0YG) on the 3.9 m Anglo-Australian
  Telescope at Siding Spring Observatory (Australia); TRES (Furesz 2008,
  PhD thesis Univ. Szeged) on the 1.5 m Tillinghast reflector at the
  F. L. Whipple Observatory (Mt. Hopkins, Arizona); and iSHELL (Rayner
  et al. 2012SPIE.8446E..2CR) on the NASA IRTF Telescope (Maunakea,
  Hawai'i). All spectra used in this paper were obtained between 2018
  November 11 and December 30 and have a minimum spectral resolution of
  R~44000. <P />(1 data file).

---------------------------------------------------------
Title: Damping rates and frequency corrections of Kepler LEGACY stars
Authors: Houdek, G.; Lund, M. N.; Trampedach, R.;
   Christensen-Dalsgaard, J.; Handberg, R.; Appourchaux, T.
2019MNRAS.487..595H    Altcode: 2019MNRAS.tmp.1157H; 2019arXiv190413170H
  Linear damping rates and modal frequency corrections of radial
  oscillation modes in selected LEGACY main-sequence stars are
  estimated by means of a non-adiabatic stability analysis. The
  selected stellar sample covers stars observed by Kepler with a large
  range of surface temperatures and surface gravities. A non-local,
  time-dependent convection model is perturbed to assess stability
  against pulsation modes. The mixing-length parameter is calibrated
  to the surface-convection-zone depth of a stellar model obtained from
  fitting adiabatic frequencies to the LEGACY observations, and two of
  the non-local convection parameters are calibrated to the corresponding
  LEGACY linewidth measurements. The remaining non-local convection
  parameters in the 1D calculations are calibrated so as to reproduce
  profiles of turbulent pressure and of the anisotropy of the turbulent
  velocity field of corresponding 3D hydrodynamical simulations. The
  atmospheric structure in the 1D stability analysis adopts a
  temperature-optical-depth relation derived from 3D hydrodynamical
  simulations. Despite the small number of parameters to adjust, we
  find good agreement with detailed shapes of both turbulent pressure
  profiles and anisotropy profiles with depth, and with damping rates
  as a function of frequency. Furthermore, we find the absolute modal
  frequency corrections, relative to a standard adiabatic pulsation
  calculation, to increase with surface temperature and surface gravity.

---------------------------------------------------------
Title: A Hot Saturn Orbiting an Oscillating Late Subgiant Discovered
    by TESS
Authors: Huber, Daniel; Chaplin, William J.; Chontos, Ashley; Kjeldsen,
   Hans; Christensen-Dalsgaard, Jørgen; Bedding, Timothy R.; Ball,
   Warrick; Brahm, Rafael; Espinoza, Nestor; Henning, Thomas; Jordán,
   Andrés; Sarkis, Paula; Knudstrup, Emil; Albrecht, Simon; Grundahl,
   Frank; Fredslund Andersen, Mads; Pallé, Pere L.; Crossfield, Ian;
   Fulton, Benjamin; Howard, Andrew W.; Isaacson, Howard T.; Weiss,
   Lauren M.; Handberg, Rasmus; Lund, Mikkel N.; Serenelli, Aldo M.;
   Rørsted Mosumgaard, Jakob; Stokholm, Amalie; Bieryla, Allyson;
   Buchhave, Lars A.; Latham, David W.; Quinn, Samuel N.; Gaidos, Eric;
   Hirano, Teruyuki; Ricker, George R.; Vanderspek, Roland K.; Seager,
   Sara; Jenkins, Jon M.; Winn, Joshua N.; Antia, H. M.; Appourchaux,
   Thierry; Basu, Sarbani; Bell, Keaton J.; Benomar, Othman; Bonanno,
   Alfio; Buzasi, Derek L.; Campante, Tiago L.; Çelik Orhan, Z.; Corsaro,
   Enrico; Cunha, Margarida S.; Davies, Guy R.; Deheuvels, Sebastien;
   Grunblatt, Samuel K.; Hasanzadeh, Amir; Di Mauro, Maria Pia; García,
   Rafael A.; Gaulme, Patrick; Girardi, Léo; Guzik, Joyce A.; Hon, Marc;
   Jiang, Chen; Kallinger, Thomas; Kawaler, Steven D.; Kuszlewicz, James
   S.; Lebreton, Yveline; Li, Tanda; Lucas, Miles; Lundkvist, Mia S.;
   Mann, Andrew W.; Mathis, Stéphane; Mathur, Savita; Mazumdar, Anwesh;
   Metcalfe, Travis S.; Miglio, Andrea; Monteiro, Mário J. P. F. G.;
   Mosser, Benoit; Noll, Anthony; Nsamba, Benard; Ong, Jia Mian Joel;
   Örtel, S.; Pereira, Filipe; Ranadive, Pritesh; Régulo, Clara;
   Rodrigues, Thaíse S.; Roxburgh, Ian W.; Silva Aguirre, Victor;
   Smalley, Barry; Schofield, Mathew; Sousa, Sérgio G.; Stassun,
   Keivan G.; Stello, Dennis; Tayar, Jamie; White, Timothy R.; Verma,
   Kuldeep; Vrard, Mathieu; Yıldız, M.; Baker, David; Bazot, Michaël;
   Beichmann, Charles; Bergmann, Christoph; Bugnet, Lisa; Cale, Bryson;
   Carlino, Roberto; Cartwright, Scott M.; Christiansen, Jessie L.;
   Ciardi, David R.; Creevey, Orlagh; Dittmann, Jason A.; Do Nascimento,
   Jose-Dias, Jr.; Van Eylen, Vincent; Fürész, Gabor; Gagné, Jonathan;
   Gao, Peter; Gazeas, Kosmas; Giddens, Frank; Hall, Oliver J.; Hekker,
   Saskia; Ireland, Michael J.; Latouf, Natasha; LeBrun, Danny; Levine,
   Alan M.; Matzko, William; Natinsky, Eva; Page, Emma; Plavchan,
   Peter; Mansouri-Samani, Masoud; McCauliff, Sean; Mullally, Susan E.;
   Orenstein, Brendan; Garcia Soto, Aylin; Paegert, Martin; van Saders,
   Jennifer L.; Schnaible, Chloe; Soderblom, David R.; Szabó, Róbert;
   Tanner, Angelle; Tinney, C. G.; Teske, Johanna; Thomas, Alexandra;
   Trampedach, Regner; Wright, Duncan; Yuan, Thomas T.; Zohrabi, Farzaneh
2019AJ....157..245H    Altcode: 2019arXiv190101643H
  We present the discovery of HD 221416 b, the first transiting planet
  identified by the Transiting Exoplanet Survey Satellite (TESS) for
  which asteroseismology of the host star is possible. HD 221416 b
  (HIP 116158, TOI-197) is a bright (V = 8.2 mag), spectroscopically
  classified subgiant that oscillates with an average frequency of
  about 430 μHz and displays a clear signature of mixed modes. The
  oscillation amplitude confirms that the redder TESS bandpass compared
  to Kepler has a small effect on the oscillations, supporting the
  expected yield of thousands of solar-like oscillators with TESS 2
  minute cadence observations. Asteroseismic modeling yields a robust
  determination of the host star radius (R <SUB>⋆</SUB> = 2.943 ±
  0.064 R <SUB>⊙</SUB>), mass (M <SUB>⋆</SUB> = 1.212 ± 0.074 M
  <SUB>⊙</SUB>), and age (4.9 ± 1.1 Gyr), and demonstrates that it has
  just started ascending the red-giant branch. Combining asteroseismology
  with transit modeling and radial-velocity observations, we show that
  the planet is a “hot Saturn” (R <SUB>p</SUB> = 9.17 ± 0.33 R
  <SUB>⊕</SUB>) with an orbital period of ∼14.3 days, irradiance
  of F = 343 ± 24 F <SUB>⊕</SUB>, and moderate mass (M <SUB>p</SUB>
  = 60.5 ± 5.7 M <SUB>⊕</SUB>) and density (ρ <SUB>p</SUB> = 0.431
  ± 0.062 g cm<SUP>-3</SUP>). The properties of HD 221416 b show that
  the host-star metallicity-planet mass correlation found in sub-Saturns
  (4-8 R <SUB>⊕</SUB>) does not extend to larger radii, indicating that
  planets in the transition between sub-Saturns and Jupiters follow a
  relatively narrow range of densities. With a density measured to ∼15%,
  HD 221416 b is one of the best characterized Saturn-size planets to
  date, augmenting the small number of known transiting planets around
  evolved stars and demonstrating the power of TESS to characterize
  exoplanets and their host stars using asteroseismology.

---------------------------------------------------------
Title: Searching for g modes. II. Unconfirmed g-mode detection in
    the power spectrum of the time series of round-trip travel time
Authors: Appourchaux, T.; Corbard, T.
2019A&A...624A.106A    Altcode: 2019arXiv190303791A
  Context. The recent claims of g-mode detection have restarted the search
  for these potentially extremely important modes. The claimed detection
  of g modes was obtained from the analysis of the power spectrum of
  the time series of round-trip travel time of p modes. <BR /> Aims:
  The goal of this paper is to reproduce these results on which the
  claims are based for confirming or invalidating the detection of
  g modes with the method used to make the claims. <BR /> Methods: We
  computed the time series of round-trip travel time using the procedure
  given in Fossat et al. (2017, A&amp;A, 604, A40), and used different
  variations of the times series for comparison. We used the recently
  calibrated GOLF data (published in Paper I) with different sampling,
  different photomultipliers, different length of data for reproducing the
  analysis. We also correlated the power spectrum with an asymptotic model
  of g-mode frequencies in a similar manner to Fossat and Schmider (2018,
  A&amp;A, 612, L1). We devised a scheme for optimising the correlation
  both for pure noise and for the GOLF data. <BR /> Results: We confirm
  the analysis performed in Fossat et al. (2017) but draw different
  conclusions. Their claims of detection of g modes cannot be confirmed
  when changing parameters such as sampling interval, length of time
  series, or photomultipliers. Other instrument such as GONG and BiSON do
  not confirm their detection. We also confirm the analysis performed in
  Fossat and Schmider (2018), but again draw different conclusions. For
  GOLF, the correlation of the power spectrum with the asymptotic model of
  g-mode frequencies for l = 1 and l = 2 show a high correlation at lag=0
  and at lag corresponding to the rotational splitting ν<SUB>l</SUB>,
  but the same occurs for pure noise due to the large number of peaks
  present in the model. In addition, other very different parameters
  defining the asymptotic model also provide a high correlation at these
  lags. We conclude that the detection performed in Fossat and Schmider
  (2018) is an artefact of the methodology.

---------------------------------------------------------
Title: VizieR Online Data Catalog: Asymmetry of oscillations in 43
    Kepler stars (Benomar+, 2018)
Authors: Benomar, O.; Goupil, M.; Belkacem, K.; Appourchaux, T.;
   Nielsen, M. B.; Bazot, M.; Gizon, L.; Hanasoge, S.; Sreenivasan,
   K. R.; Marchand, B.
2019yCat..18570119B    Altcode:
  In this work, the considered ensemble of stars is a subset of the Kepler
  LEGACY sample (Lund+ 2017, J/ApJ/835/172). We selected 43 stars for
  analysis out of 66 of the LEGACY sample. The current analysis uses the
  unweighted power spectra provided by the Kepler Asteroseismic Science
  Operations Center (KASOC) pipeline (http://kasoc.phys.au.dk/). <P />(2
  data files).

---------------------------------------------------------
Title: The Asteroseismic Target List for Solar-like Oscillators
    Observed in 2 minute Cadence with the Transiting Exoplanet Survey
    Satellite
Authors: Schofield, Mathew; Chaplin, William J.; Huber, Daniel;
   Campante, Tiago L.; Davies, Guy R.; Miglio, Andrea; Ball, Warrick
   H.; Appourchaux, Thierry; Basu, Sarbani; Bedding, Timothy R.;
   Christensen-Dalsgaard, Jørgen; Creevey, Orlagh; García, Rafael A.;
   Handberg, Rasmus; Kawaler, Steven D.; Kjeldsen, Hans; Latham, David W.;
   Lund, Mikkel N.; Metcalfe, Travis S.; Ricker, George R.; Serenelli,
   Aldo; Silva Aguirre, Victor; Stello, Dennis; Vanderspek, Roland
2019ApJS..241...12S    Altcode: 2019arXiv190110148S
  We present the target list of solar-type stars to be observed in
  short-cadence (2 minute) for asteroseismology by the NASA Transiting
  Exoplanet Survey Satellite (TESS) during its 2 year nominal survey
  mission. The solar-like Asteroseismic Target List (ATL) is comprised
  of bright, cool main-sequence and subgiant stars and forms part of the
  larger target list of the TESS Asteroseismic Science Consortium. The
  ATL uses the Gaia Data Release 2 and the Extended Hipparcos Compilation
  (XHIP) to derive fundamental stellar properties, to calculate detection
  probabilities, and to produce a rank-ordered target list. We provide a
  detailed description of how the ATL was produced and calculate expected
  yields for solar-like oscillators based on the nominal photometric
  performance by TESS. We also provide a publicly available source code
  that can be used to reproduce the ATL, thereby enabling comparisons
  of asteroseismic results from TESS with predictions from synthetic
  stellar populations.

---------------------------------------------------------
Title: First measurements of Jupiter's zonal winds with visible
    imaging spectroscopy
Authors: Gonçalves, Ivan; Schmider, F. X.; Gaulme, Patrick;
   Morales-Juberías, Raúl; Guillot, Tristan; Rivet, Jean-Pierre;
   Appourchaux, Thierry; Boumier, Patrick; Jackiewicz, Jason; Sato,
   Bun'ei; Ida, Shigeru; Ikoma, Masahiro; Mékarnia, Djamel; Underwood,
   Thomas A.; Voelz, David
2019Icar..319..795G    Altcode:
  We present the first measurements of Jupiter's wind profile ever
  obtained with Doppler velocity measurements in the visible. Hitherto,
  knowledge about atmospheric dynamics has been obtained with
  cloud-tracking techniques, which consist of tracking visible features
  from images taken at different dates. However, cloud tracking indicates
  the motion of large cloud structures, which is an indication of
  the speed of iso-pressure regions, rather than the speed of the
  actual atmospheric particles. Doppler imaging is as challenging -
  motions are usually less than 100 m s-<SUP>1</SUP> - as appealing
  because it measures the speed of cloud particles instead of large
  cloud structures. Significant difference could appear in the case of
  atmospheric waves interfering with cloud structures. Here we present
  the first scientific results of a Doppler imaging spectrometer that
  is dedicated to giant-planet seismology and atmospheric dynamics by
  providing instantaneous line-of-sight-velocity maps of the planets of
  the solar system. The instrument has been developed in the framework
  of the projects JOVIAL (Jovian Oscillations through Velocity Images At
  several Longitudes) and JIVE in NM (Jovian Interiors from Velocimetry
  Experiment in New Mexico). It is a Fourier transform spectrometer with a
  fixed optical path difference working in the mid-visible domain, which
  monitors the position of solar Fraunhofer lines that are reflected
  in the planets' upper atmospheres. After describing the instrument
  principle and the different steps of data reduction, we report
  measurement of the average zonal wind speed of Jupiter, as a function
  of latitude, from datasets obtained in 2015 and 2016 with two different
  telescopes, when the planet was close to its opposition. Our results
  are consistent between the two years. We compare the results with wind
  profiles obtained by cloud tracking on HST (Hubble Space Telescope)
  images taken at the same epoch, and identify a significant discrepancy
  in the North Equatorial Belt and northern part of the Equatorial Zone.

---------------------------------------------------------
Title: Searching for g modes. I. A new calibration of the GOLF
    instrument
Authors: Appourchaux, T.; Boumier, P.; Leibacher, J. W.; Corbard, T.
2018A&A...617A.108A    Altcode: 2018arXiv180700998A
  Context. The recent claims of g-mode detection have restarted the
  search for these potentially extremely important modes. These claims
  can be reassessed in view of the different data sets available from
  the SoHO instruments and ground-based instruments. <BR /> Aims: We
  produce a new calibration of the GOLF data with a more consistent
  p-mode amplitude and a more consistent time shift correction compared
  to the time series used in the past. <BR /> Methods: The calibration
  of 22 yr of GOLF data is done with a simpler approach that uses
  only the predictive radial velocity of the SoHO spacecraft as a
  reference. Using p modes, we measure and correct the time shift between
  ground- and space-based instruments and the GOLF instrument. <BR />
  Results: The p-mode velocity calibration is now consistent to within
  a few percent with other instruments. The remaining time shifts are
  within ±5 s for 99.8% of the time series. <P />The new calibrated
  series (FITS) are available at the CDS via anonymous ftp to <A
  href="http://cdsarc.u-strasbg.fr">http://cdsarc.u-strasbg.fr</A>
  (ftp://130.79.128.5) or via <A
  href="http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/617/A108">http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/617/A108</A>

---------------------------------------------------------
Title: First measurements of the Jovian zonal winds profile through
    visible Doppler spectroscopy
Authors: Schmider, François-Xavier; Goncalves, Ivan; Gaulme, Patrick;
   Morales-Jubieras, Raul; Guillot, Tristan; Appourchaux, Thierry;
   Boumier, Patrick; Jackiewicz, Jason; Underwood, Thomas; Voelz, David;
   Sato, Bun'ei; Ida, Shigeru; Ikoma, Masahiro; Rivet, Jean-Pierre
2018EPSC...12..433S    Altcode:
  We present the first measurements of Jupiter's wind profile ever
  obtained with radial-velocity measurements. We report measurement of
  the average zonal wind speed of Jupiter, as function of latitude, from
  datasets obtained in 2016 and 2017 during the planet's opposition. We
  compare our results with simultaneous wind profiles obtained by cloud
  tracking from Hubble-space-telescope images, and point out a significant
  discrepancy at the latitude of the hot spots in the northern equatorial
  band, around 5° N.

---------------------------------------------------------
Title: Asteroseismic and orbital analysis of the triple star system
    HD 188753 observed by Kepler
Authors: Marcadon, F.; Appourchaux, T.; Marques, J. P.
2018A&A...617A...2M    Altcode: 2018arXiv180409296M
  Context. The NASA Kepler space telescope has detected solar-like
  oscillations in several hundreds of single stars, thereby providing a
  way to determine precise stellar parameters using asteroseismology. <BR
  /> Aims: In this work, we aim to derive the fundamental parameters of
  a close triple star system, HD 188753, for which asteroseismic and
  astrometric observations allow independent measurements of stellar
  masses. <BR /> Methods: We used six months of Kepler photometry
  available for HD 188753 to detect the oscillation envelopes of the
  two brightest stars. For each star, we extracted the individual mode
  frequencies by fitting the power spectrum using a maximum likelihood
  estimation approach. We then derived initial guesses of the stellar
  masses and ages based on two seismic parameters and on a characteristic
  frequency ratio, and modelled the two components independently with
  the stellar evolution code CESTAM. In addition, we derived the masses
  of the three stars by applying a Bayesian analysis to the position
  and radial-velocity measurements of the system. <BR /> Results:
  Based on stellar modelling, the mean common age of the system is
  10.8 ± 0.2 Gyr and the masses of the two seismic components are
  M<SUB>A</SUB> = 0.99 ± 0.01 M<SUB>⊙</SUB> and M<SUB>Ba</SUB>
  = 0.86 ± 0.01 M<SUB>⊙</SUB>. From the mass ratio of the close
  pair, M<SUB>Bb</SUB>/M<SUB>Ba</SUB> = 0.767 ± 0.006, the mass of
  the faintest star is M<SUB>Bb</SUB> = 0.66 ± 0.01 M<SUB>⊙</SUB>
  and the total seismic mass of the system is then M<SUB>syst</SUB> =
  2.51 ± 0.02 M<SUB>⊙</SUB>. This value agrees perfectly with the
  total mass derived from our orbital analysis, M<SUB>syst</SUB> =
  2.51<SUB>-0.18</SUB><SUP>+0.20</SUP> M<SUB>⊙</SUB>, and leads to
  the best current estimate of the parallax for the system, π = 21.9
  ± 0.2 mas. In addition, the minimal relative inclination between the
  inner and outer orbits is 10.9° ± 1.5°, implying that the system
  does not have a coplanar configuration.

---------------------------------------------------------
Title: The High Resolution Telescope (HRT) of the Polarimetric and
    Helioseismic Imager (PHI) onboard Solar Orbiter
Authors: Gandorfer, A.; Grauf, B.; Staub, J.; Bischoff, J.; Woch, J.;
   Hirzberger, J.; Solanki, S. K.; Álvarez-Herrero, A.; García Parejo,
   P.; Schmidt, W.; Volkmer, R.; Appourchaux, T.; del Toro Iniesta, J. C.
2018SPIE10698E..4NG    Altcode:
  Solar Orbiter is a joint mission of ESA and NASA scheduled for
  launch in 2020. Solar Orbiter is a complete and unique heliophysics
  mission, combining remote sensing and in-situ analysis; its special
  elliptical orbit allows viewing the Sun from a distance of only 0.28
  AU, and - leaving the ecliptic plane - to observe the solar poles from
  a hitherto unexplored vantage point. One of the key instruments for
  Solar Orbiter's science is the "Polarimetric and Helioseismic Imager"
  (PHI), which will provide maps of the solar surface magnetic fields and
  the gas flows on the visible solar surface. Two telescopes, a full disc
  imager, and a high resolution channel feed a common Fabry-Perot based
  tunable filter and thus allow sampling a single Fraunhofer line at 617.3
  nm with high spectral resolution; a polarization modulation system
  makes the system sensitive to the full state of polarization. From
  the analysis of the Doppler shift and the magnetically induced Zeeman
  polarization in this line, the magnetic field and the line-of-sight
  gas motions can be detected for each point in the image. In this
  paper we describe the opto-mechanical system design of the high
  resolution telescope. It is based on a decentred Ritchey-Chrétien
  two-mirror telescope. The telescope includes a Barlow type magnifier
  lens group, which is used as in-orbit focus compensator, and a beam
  splitter, which sends a small fraction of the collected light onto
  a fast camera, which provides the error signals for the actively
  controlled secondary mirror compensating for spacecraft jitter and other
  disturbances. The elliptical orbit of the spacecraft poses high demands
  on the thermo-mechanical stability. The varying size of the solar disk
  image requires a special false-light suppression architecture, which is
  briefly described. In combination with a heat-rejecting entrance window,
  the optical energy impinging on the polarimetric and spectral analysis
  system is efficiently reduced. We show how the design can preserve the
  diffraction-limited imaging performance over the design temperature
  range of -20°C to +60°C. The decentred hyperbolical mirrors require
  special measures for the inter-alignment and their alignment with
  respect to the mechanical structure. A system of alignment flats and
  mechanical references is used for this purpose. We will describe the
  steps of the alignment procedure, and the dedicated optical ground
  support equipment, which are needed to reach the diffraction limited
  performance of the telescope. We will also report on the verification
  of the telescope performance, both - in ambient condition - and in
  vacuum at different temperatures.

---------------------------------------------------------
Title: VizieR Online Data Catalog: Sun velocities from GOLF instrument
    (Appourchaux+, 2018)
Authors: Appourchaux, T.; Boumier, P.; Leibacher, J. W.; Corbard, T.
2018yCat..36170108A    Altcode:
  Three time series as FITS file comprising 34797600 data points of GOLF
  velocity in m/s sampled at 20 sec (no time provided). The time series
  starts on April 11, 1996 0:00 UT and ends on April 10, 2018 23:59:40
  UT. The time series are provided for the photomultipliers PM1 and PM2,
  and their arithmetic average. <P />(2 data files).

---------------------------------------------------------
Title: Exploring the poles of the Sun: POLAR Investigation of the Sun
    (POLARIS+)
Authors: Appourchaux, Thierry
2018tess.conf11001A    Altcode:
  The POLAR Investigation of the Sun (POLARIS+) idea is one that has
  been developed over a number of years, and is supported by scientists
  in Europe, US, India and Japan so far. It uses a combination of a
  gravity assist and solar sail propulsion to place a spacecraft in a
  0.48 AU circular orbit around the Sun with an inclination of 75º
  with respect to solar equator. In this orbit, at least 59% of the
  time will be spent at latitudes higher than the maximum latitude
  reached by Solar Orbiter (»32º). This first extended view of the
  high-latitude regions of the Sun will enable crucial observations
  not possible from the ecliptic viewpoint or from Solar Orbiter. While
  Solar Orbiter will give the first glimpse of the high latitude magnetic
  field and flows to probe the solar dynamo, it does not have sufficient
  viewing of the polar regions to achieve POLARIS+ primary objective:
  determining the relation between the magnetism and dynamics of the
  Sun's polar regions and the solar cycle. <P />The scientific payload
  needed to achieve these objectives consists of a set of remote-sensing
  instruments. All instruments have a very high TRL being derived
  from past and current missions such as Solar Orbiter. The payload
  will consist of remote sensing instruments: &lt;li&gt;Dopplergraph
  and magnetograph imager&lt;/li&gt; &lt;li&gt;White-light coronagraph
  (classical and heliospheric)&lt;/li&gt; &lt;li&gt;EUV imager&lt;/li&gt;
  &lt;li&gt;UV spectrograph&lt;/li&gt; &lt;li&gt;Total Solar Irradiance
  monitor&lt;/li&gt; <P />All imaging instruments will have a typical
  resolution of 2 to 4 arcseconds. In-situ instruments could also be
  considered as an interesting addition for following up on the success
  of the ESA's Ulysses mission. <P />Extended observations from high
  latitudes will revolutionize our understanding of the internal structure
  and dynamics of the Sun and its atmosphere. The rapid, 4-month polar
  orbit (allowed by the use of solar sails) combined with a suite of
  remote-sensing instrumentation further enables unprecedented studies
  of the physical connection between the Sun and the corona. Moreover,
  POLARIS+ serves as a pathfinder for a permanent solar polar sentinel
  for space-weather prediction in support of NASA's Vision for Space
  Exploration, of ESA's Space Situational Awareness and a broad range
  of other programs affected by space weather.

---------------------------------------------------------
Title: Asymmetry of Line Profiles of Stellar Oscillations Measured
by Kepler for Ensembles of Solar-like Oscillators: Impact on Mode
    Frequencies and Dependence on Effective Temperature
Authors: Benomar, O.; Goupil, Mjo.; Belkacem, K.; Appourchaux, T.;
   Nielsen, M. B.; Bazot, M.; Gizon, L.; Hanasoge, S.; Sreenivasan,
   K. R.; Marchand, B.
2018ApJ...857..119B    Altcode: 2018arXiv180406117B
  Oscillation properties are usually measured by fitting symmetric
  Lorentzian profiles to the power spectra of Sun-like stars. However,
  the line profiles of solar oscillations have been observed to be
  asymmetrical for the Sun. The physical origin of this line asymmetry is
  not fully understood; though, it should depend on the depth dependence
  of the source of wave excitation (convective turbulence) and details of
  the observable (velocity or intensity). For oscillations of the Sun,
  it has been shown that neglecting the asymmetry leads to systematic
  errors in the frequency determination. This could subsequently
  affect the results of seismic inferences of the solar internal
  structure. Using light curves from the Kepler spacecraft, we have
  measured mode asymmetries in 43 stars. We confirm that neglecting the
  asymmetry leads to systematic errors that can exceed the 1σ confidence
  intervals for seismic observations longer than one year. Therefore,
  the application of an asymmetric Lorentzian profile should be favored
  to improve the accuracy of the internal stellar structure and stellar
  fundamental parameters. We also show that the asymmetry changes sign
  between cool Sun-like stars and hotter stars. This provides the best
  constraints to date on the location of the excitation sources across
  the Hertzsprung-Russel diagram.

---------------------------------------------------------
Title: Helioseismology: Observations and Space Missions
Authors: Palle, P. L.; Appourchaux, T.; Christensen-Dalsgaard, J.;
   Garcia, R. A.
2018arXiv180200674P    Altcode:
  The great success of Helioseismology resides in the remarkable
  progress achieved in the understanding of the structure and dynamics
  of the solar interior. This success mainly relies on the ability to
  conceive, implement, and operate specific instrumentation with enough
  sensitivity to detect and measure small fluctuations (in velocity
  and/or intensity) on the solar surface that are well below one meter
  per second or a few parts per million. Furthermore the limitation of
  the ground observations imposing the day-night cycle (thus a periodic
  discontinuity in the observations) was overcome with the deployment of
  ground-based networks --properly placed at different longitudes all
  over the Earth-- allowing longer and continuous observations of the
  Sun and consequently increasing their duty cycles. In this chapter,
  we start by a short historical overview of helioseismology. Then we
  describe the different techniques used to do helioseismic analyses along
  with a description of the main instrumental concepts. We in particular
  focus on the instruments that have been operating long enough to study
  the solar magnetic activity. Finally, we give a highlight of the main
  results obtained with such high-duty cycle observations (&gt;80%)
  lasting over the last few decades.

---------------------------------------------------------
Title: VizieR Online Data Catalog: 61 main-sequence and subgiant
    oscillations (Appourchaux+, 2012)
Authors: Appourchaux, T.; Chaplin, W. J.; Garcia, R. A.; Gruberbauer,
   M.; Verner, G. A.; Antia, H. M.; Benomar, O.; Campante, T. L.; Davies,
   G. R.; Deheuvels, S.; Handberg, R.; Hekker, S.; Howe, R.; Regulo,
   C.; Salabert, D.; Bedding, T. R.; White, T. R.; Ballot, J.; Mathur,
   S.; Silva Aguirre, V.; Elsworth, Y. P.; Basu, S.; Gilliland, R. L.;
   Christensen-Dalsgaard, J.; Kjeldsen, H.; Uddin, K.; Stumpe, M. C.;
   Barclay, T.
2017yCat..35430054A    Altcode:
  Kepler observations are obtained in two different operating
  modes: long cadence (LC) and short cadence (SC) (Gilliland et al.,
  2010ApJ...713L.160G; Jenkins et al., 2010ApJ...713L..87J). This work is
  based on SC data. For the brightest stars (down to Kepler magnitude,
  Kp~=12), SC observations can be obtained for a limited number of
  stars (up to 512 at any given time) with a faster sampling cadence
  of 58.84876s (Nyquist frequency of ~8.5mHz), which permits a more
  precise transit timing and the performance of asteroseismology. Kepler
  observations are divided into three-month-long quarters (Q). A subset
  of 61 solar-type stars observed during quarters Q5-Q7 (March 22,
  2010 to December 22, 2010) were chosen because they have oscillation
  modes with high signal-to-noise ratios. This length of data gives a
  frequency resolution of about 0.04uHz. <P />(2 data files).

---------------------------------------------------------
Title: Conception and test of Echoes, a spectro-imager dedicated to
    the seismology of Jupiter
Authors: Soulat, L.; Schmider, F. -X.; Robbe-Dubois, S.; Appourchaux,
   T.; Gaulme, P.; Bresson, Y.; Gay, J.; Daban, J. -B.; Gouvret, C.
2017SPIE10564E..1VS    Altcode:
  Echoes is a project of a spaceborne Doppler Spectro-Imager (DSI) which
  has been proposed as payload to the JUICE mission project selected
  in the Cosmic Vision program of the European Space Agency (ESA). It
  is a Fourier transform spectrometer which measures phase shifts in
  the interference patterns induced by Doppler shifts of spectral lines
  reflected at the surface of the planet. Dedicated to the seismology of
  Jupiter, the instrument is designed to analyze the periodic movements
  induced by internal acoustic modes of the planet. It will allow
  the knowledge of the internal structure of Jupiter, in particular
  of the central region, which is essential for the comprehension of
  the scenario of the giant planets' formation. The optical design is
  based on a modified Mach-Zehnder interferometer operating in the
  visible domain and takes carefully into account the sensitivity
  of the optical path difference to the temperature. The instrument
  produces simultaneously four images in quadrature which allows the
  measurement of the phase without being contaminated by the continuum
  component of the incident light. We expect a noise level less than 1
  cm<SUP>2</SUP>s<SUP>-2</SUP>µHz<SUP>-1</SUP> in the frequency range
  [0.5 -10] mHz. In this paper, we present the prototype implemented
  at the Observatoire de la Côte d'Azur (OCA) in collaboration with
  Institut d'Astrophysique Spatiale (IAS) to study the real performances
  in laboratory and to demonstrate the capability to reach the required
  Technology Readiness Level 5.

---------------------------------------------------------
Title: VizieR Online Data Catalog: Asterosismology for solar analogues
    16 Cyg A/B (Davies+, 2015)
Authors: Davies, G. R.; Chaplin, W. J.; Farr, W. M.; Garcia, R. A.;
   Lund, M. N.; Mathis, S.; Metcalfe, T. S.; Appourchaux, T.; Basu, S.;
   Benomar, O.; Campante, T. L.; Ceillier, T.; Elsworth, Y.; Handberg,
   R.; Salabert, D.; Stello, D.
2017yCat..74462959D    Altcode:
  Both 16 Cyg A and B are brighter (V~6) than the saturation limit for
  which Kepler observations were designed. However, it was possible to
  capture the full stellar flux by using custom photometric aperture
  masks. Thus, 928 d of short-cadence observations (Gilliland et
  al. 2010ApJ...713L.160G) - from Quarter 7 to 16 - were generated using
  simple aperture photometry (Jenkins et al. 2010ApJ...713L..87J) and
  then corrected for instrumental perturbations following the methods
  described by Garcia et al. (2011MNRAS.414L...6G). The final light
  curves used for asteroseismic analyses were high-pass filtered using
  a triangular smooth of 4 d width and have a duty cycle of 90.5 per
  cent. The power density spectra were computed using a Lomb-Scargle
  algorithm. <P />(2 data files).

---------------------------------------------------------
Title: Definition of a metrology servo-system for a solar imaging
    fourier transform spectrometer working in the far UV (IFTSUV)
Authors: Ruiz de Galarreta Fanju, C.; Philippon, A.; Bouzit, M.;
   Appourchaux, T.; Vial, J. -C.; Maillard, J. -P.; Lemaire, P.
2017SPIE10564E..3ER    Altcode:
  The understanding of the solar outer atmosphere requires a simultaneous
  combination of imaging and spectral observations concerning the far UV
  lines that arise from the high chromospheres up to the corona. These
  observations must be performed with enough spectral, spatial and
  temporal resolution to reveal the small atmospheric structures and to
  resolve the solar dynamics. An Imaging Fourier Transform Spectrometer
  working in the far-UV (IFTSUV, Figure 1) is an attractive instrumental
  solution to fulfill these requirements. However, due to the short
  wavelength, to preserve IFTSUV spectral precision and Signal to Noise
  Ratio (SNR) requires a high optical surface quality and a very accurate
  (linear and angular) metrology to maintain the optical path difference
  (OPD) during the entire scanning process by: optical path difference
  sampling trigger; and dynamic alignment for tip/tilt compensation
  (Figure 2).

---------------------------------------------------------
Title: PLATO as it is : A legacy mission for Galactic archaeology
Authors: Miglio, A.; Chiappini, C.; Mosser, B.; Davies, G. R.;
   Freeman, K.; Girardi, L.; Jofré, P.; Kawata, D.; Rendle, B. M.;
   Valentini, M.; Casagrande, L.; Chaplin, W. J.; Gilmore, G.; Hawkins,
   K.; Holl, B.; Appourchaux, T.; Belkacem, K.; Bossini, D.; Brogaard,
   K.; Goupil, M. -J.; Montalbán, J.; Noels, A.; Anders, F.; Rodrigues,
   T.; Piotto, G.; Pollacco, D.; Rauer, H.; Prieto, C. Allende; Avelino,
   P. P.; Babusiaux, C.; Barban, C.; Barbuy, B.; Basu, S.; Baudin, F.;
   Benomar, O.; Bienaymé, O.; Binney, J.; Bland-Hawthorn, J.; Bressan,
   A.; Cacciari, C.; Campante, T. L.; Cassisi, S.; Christensen-Dalsgaard,
   J.; Combes, F.; Creevey, O.; Cunha, M. S.; Jong, R. S.; Laverny, P.;
   Degl'Innocenti, S.; Deheuvels, S.; Depagne, É.; Ridder, J.; Matteo,
   P. Di; Mauro, M. P. Di; Dupret, M. -A.; Eggenberger, P.; Elsworth,
   Y.; Famaey, B.; Feltzing, S.; García, R. A.; Gerhard, O.; Gibson,
   B. K.; Gizon, L.; Haywood, M.; Handberg, R.; Heiter, U.; Hekker,
   S.; Huber, D.; Ibata, R.; Katz, D.; Kawaler, S. D.; Kjeldsen, H.;
   Kurtz, D. W.; Lagarde, N.; Lebreton, Y.; Lund, M. N.; Majewski, S. R.;
   Marigo, P.; Martig, M.; Mathur, S.; Minchev, I.; Morel, T.; Ortolani,
   S.; Pinsonneault, M. H.; Plez, B.; Moroni, P. G. Prada; Pricopi, D.;
   Recio-Blanco, A.; Reylé, C.; Robin, A.; Roxburgh, I. W.; Salaris,
   M.; Santiago, B. X.; Schiavon, R.; Serenelli, A.; Sharma, S.; Aguirre,
   V. Silva; Soubiran, C.; Steinmetz, M.; Stello, D.; Strassmeier, K. G.;
   Ventura, P.; Ventura, R.; Walton, N. A.; Worley, C. C.
2017AN....338..644M    Altcode: 2017arXiv170603778M
  Deciphering the assembly history of the Milky Way is a formidable
  task, which becomes possible only if one can produce high-resolution
  chrono-chemo-kinematical maps of the Galaxy. Data from large-scale
  astrometric and spectroscopic surveys will soon provide us with a
  well-defined view of the current chemo-kinematical structure of the
  Milky Way, but will only enable a blurred view on the temporal sequence
  that led to the present-day Galaxy. As demonstrated by the (ongoing)
  exploitation of data from the pioneering photometric missions CoRoT,
  Kepler, and K2, asteroseismology provides the way forward: solar-like
  oscillating giants are excellent evolutionary clocks thanks to the
  availability of seismic constraints on their mass and to the tight
  age-initial-mass relation they adhere to. In this paper we identify
  five key outstanding questions relating to the formation and evolution
  of the Milky Way that will need precise and accurate ages for large
  samples of stars to be addressed, and we identify the requirements
  in terms of number of targets and the precision on the stellar
  properties that are needed to tackle such questions. By quantifying
  the asteroseismic yields expected from PLATO for red-giant stars, we
  demonstrate that these requirements are within the capabilities of the
  current instrument design, provided that observations are sufficiently
  long to identify the evolutionary state and allow robust and precise
  determination of acoustic-mode frequencies. This will allow us to
  harvest data of sufficient quality to reach a 10% precision in age. This
  is a fundamental pre-requisite to then reach the more ambitious goal
  of a similar level of accuracy, which will only be possible if we
  have to hand a careful appraisal of systematic uncertainties on age
  deriving from our limited understanding of stellar physics, a goal
  which conveniently falls within the main aims of PLATO's core science.

---------------------------------------------------------
Title: SOLARIS: Solar Sail Investigation of the Sun
Authors: Appourchaux, Thierry; Auchère, Frédéric; Antonucci, Ester;
   Gizon, Laurent; MacDonald, Malcolm; Hara, Hirohisa; Sekii, Takashi;
   Moses, Daniel; Vourlidas, Angelos
2017arXiv170708193A    Altcode:
  In this paper, we detail the scientific objectives and outline
  a strawman payload of the SOLAR sail Investigation of the Sun
  (SOLARIS). The science objectives are to study the 3D structure
  of the solar magnetic and velocity field, the variation of total
  solar irradiance with latitude, and the structure of the corona. We
  show how we can meet these science objective using solar-sail
  technologies currently under development. We provide a tentative
  mission profile considering several trade-off approaches. We also
  provide a tentative mass budget breakdown and a perspective for a
  programmatic implementation.

---------------------------------------------------------
Title: Kepler observations of the asteroseismic binary HD 176465
Authors: White, T. R.; Benomar, O.; Silva Aguirre, V.; Ball, W. H.;
   Bedding, T. R.; Chaplin, W. J.; Christensen-Dalsgaard, J.; Garcia,
   R. A.; Gizon, L.; Stello, D.; Aigrain, S.; Antia, H. M.; Appourchaux,
   T.; Bazot, M.; Campante, T. L.; Creevey, O. L.; Davies, G. R.;
   Elsworth, Y. P.; Gaulme, P.; Handberg, R.; Hekker, S.; Houdek,
   G.; Howe, R.; Huber, D.; Karoff, C.; Marques, J. P.; Mathur, S.;
   McQuillan, A.; Metcalfe, T. S.; Mosser, B.; Nielsen, M. B.; Régulo,
   C.; Salabert, D.; Stahn, T.
2017A&A...601A..82W    Altcode: 2016arXiv160909581W; 2016A&A...601A..82W
  Binary star systems are important for understanding stellar structure
  and evolution, and are especially useful when oscillations can be
  detected and analysed with asteroseismology. However, only four
  systems are known in which solar-like oscillations are detected in
  both components. Here, we analyse the fifth such system, HD 176465,
  which was observed by Kepler. We carefully analysed the system's
  power spectrum to measure individual mode frequencies, adapting our
  methods where necessary to accommodate the fact that both stars
  oscillate in a similar frequency range. We also modelled the two
  stars independently by fitting stellar models to the frequencies and
  complementaryparameters. We are able to cleanly separate the oscillation
  modes in both systems. The stellar models produce compatible ages and
  initial compositions for the stars, as is expected from their common
  and contemporaneous origin. Combining the individual ages, the system
  is about 3.0 ± 0.5 Gyr old. The two components of HD 176465 are young
  physically-similar oscillating solar analogues, the first such system
  to be found, and provide important constraints for stellar evolution
  and asteroseismology.

---------------------------------------------------------
Title: Future Mission Concepts for Helioseismology
Authors: Sekii, Takashi; Appourchaux, Thierry; Fleck, Bernhard;
   Turck-Chièze, Sylvaine
2017hdsi.book..291S    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Helioseismology with Solar Orbiter
Authors: Löptien, Björn; Birch, Aaron C.; Gizon, Laurent; Schou,
   Jesper; Appourchaux, Thierry; Blanco Rodríguez, Julián; Cally,
   Paul S.; Dominguez-Tagle, Carlos; Gandorfer, Achim; Hill, Frank;
   Hirzberger, Johann; Scherrer, Philip H.; Solanki, Sami K.
2017hdsi.book..257L    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: A Distant Mirror: Solar Oscillations Observed on Neptune by
    the Kepler K2 Mission
Authors: Gaulme, P.; Rowe, J. F.; Bedding, T. R.; Benomar, O.;
   Corsaro, E.; Davies, G. R.; Hale, S. J.; Howe, R.; Garcia, R. A.;
   Huber, D.; Jiménez, A.; Mathur, S.; Mosser, B.; Appourchaux, T.;
   Boumier, P.; Jackiewicz, J.; Leibacher, J.; Schmider, F. -X.; Hammel,
   H. B.; Lissauer, J. J.; Marley, M. S.; Simon, A. A.; Chaplin, W. J.;
   Elsworth, Y.; Guzik, J. A.; Murphy, N.; Silva Aguirre, V.
2016ApJ...833L..13G    Altcode: 2016arXiv161204287G
  Starting in 2014 December, Kepler K 2 observed Neptune continuously
  for 49 days at a 1 minute cadence. The goals consisted of studying its
  atmospheric dynamics, detecting its global acoustic oscillations, and
  those of the Sun, which we report on here. We present the first indirect
  detection of solar oscillations in intensity measurements. Beyond
  the remarkable technical performance, it indicates how Kepler would
  see a star like the Sun. The result from the global asteroseismic
  approach, which consists of measuring the oscillation frequency
  at maximum amplitude ν <SUB>max</SUB> and the mean frequency
  separation between mode overtones Δν, is surprising as the ν
  <SUB>max</SUB> measured from Neptune photometry is larger than the
  accepted value. Compared to the usual reference ν <SUB>max,⊙</SUB>
  = 3100 μHz, the asteroseismic scaling relations therefore make the
  solar mass and radius appear larger by 13.8 ± 5.8% and 4.3 ± 1.9%,
  respectively. The higher ν <SUB>max</SUB> is caused by a combination
  of the value of ν <SUB>max,⊙</SUB>, being larger at the time
  of observations than the usual reference from SOHO/VIRGO/SPM data
  (3160 ± 10 μHz), and the noise level of the K 2 time series, being
  10 times larger than VIRGO’s. The peak-bagging method provides
  more consistent results: despite a low signal-to-noise ratio (S/N),
  we model 10 overtones for degrees ℓ = 0, 1, 2. We compare the K 2
  data with simultaneous SOHO/VIRGO/SPM photometry and BiSON velocity
  measurements. The individual frequencies, widths, and amplitudes mostly
  match those from VIRGO and BiSON within 1σ, except for the few peaks
  with the lowest S/N.

---------------------------------------------------------
Title: Far side Helioseismology with Solar Orbiter
Authors: Appourchaux, T.; Birch, A.; Gizon, L. C.; Löptien, B.;
   Schou, J.; Solanki, S. K.; del Toro Iniesta, J. C.; Gandorfer, A.;
   Hirzberger, J.; Alvarez-Herrero, A.; Woch, J. G.; Schmidt, W.
2016AGUFMSH43A2554A    Altcode:
  The Solar Orbiter mission, to be launched in October 2018, will
  carry a suite of remote sensing and in-situ instruments, including
  the Polarimetric and Helioseismic Imager (PHI). PHI will deliver
  high-cadence images of the Sun in intensity and Doppler velocity
  suitable for carrying out novel helioseismic studies. The orbit
  of the Solar Orbiter spacecraft will reach a solar latitude up to
  34 degrees by the end of the extended mission and thus will enable
  the first local helioseismology studies of the polar regions. The
  full range of Earth-Sun-spacecraft angles provided by the orbit will
  enable helioseismology from two vantage points by combining PHI with
  another instrument: stereoscopic helioseismology will allow the study
  of the deep solar interior and a better understanding of the physics
  of solar oscillations in both quiet Sun and sunspots. In this paper
  we will review the helioseismic objectives achievable with PHI, and
  will also give a short status report of the development of the Flight
  Model of PHI.

---------------------------------------------------------
Title: Detection of Solar-like Oscillations, Observational
    Constraints, and Stellar Models for θ Cyg, the Brightest Star
    Observed By the Kepler Mission
Authors: Guzik, J. A.; Houdek, G.; Chaplin, W. J.; Smalley, B.; Kurtz,
   D. W.; Gilliland, R. L.; Mullally, F.; Rowe, J. F.; Bryson, S. T.;
   Still, M. D.; Antoci, V.; Appourchaux, T.; Basu, S.; Bedding, T. R.;
   Benomar, O.; Garcia, R. A.; Huber, D.; Kjeldsen, H.; Latham, D. W.;
   Metcalfe, T. S.; Pápics, P. I.; White, T. R.; Aerts, C.; Ballot, J.;
   Boyajian, T. S.; Briquet, M.; Bruntt, H.; Buchhave, L. A.; Campante,
   T. L.; Catanzaro, G.; Christensen-Dalsgaard, J.; Davies, G. R.;
   Doğan, G.; Dragomir, D.; Doyle, A. P.; Elsworth, Y.; Frasca, A.;
   Gaulme, P.; Gruberbauer, M.; Handberg, R.; Hekker, S.; Karoff, C.;
   Lehmann, H.; Mathias, P.; Mathur, S.; Miglio, A.; Molenda-Żakowicz,
   J.; Mosser, B.; Murphy, S. J.; Régulo, C.; Ripepi, V.; Salabert,
   D.; Sousa, S. G.; Stello, D.; Uytterhoeven, K.
2016ApJ...831...17G    Altcode: 2016arXiv160701035G
  θ Cygni is an F3 spectral type magnitude V = 4.48 main-sequence star
  that was the brightest star observed by the original Kepler spacecraft
  mission. Short-cadence (58.8 s) photometric data using a custom
  aperture were first obtained during Quarter 6 (2010 June-September) and
  subsequently in Quarters 8 and 12-17. We present analyses of solar-like
  oscillations based on Q6 and Q8 data, identifying angular degree l = 0,
  1, and 2 modes with frequencies of 1000-2700 μHz, a large frequency
  separation of 83.9 ± 0.4 μHz, and maximum oscillation amplitude
  at frequency ν <SUB>max</SUB> = 1829 ± 54 μHz. We also present
  analyses of new ground-based spectroscopic observations, which,
  combined with interferometric angular diameter measurements, give T
  <SUB>eff</SUB> = 6697 ± 78 K, radius 1.49 ± 0.03 R <SUB>⊙</SUB>,
  [Fe/H] = -0.02 ± 0.06 dex, and log g = 4.23 ± 0.03. We calculate
  stellar models matching these constraints using the Yale Rotating
  Evolution Code and the Asteroseismic Modeling Portal. The best-fit
  models have masses of 1.35-1.39 M <SUB>⊙</SUB> and ages of 1.0-1.6
  Gyr. θ Cyg’s T <SUB>eff</SUB> and log g place it cooler than the red
  edge of the γ Doradus instability region established from pre-Kepler
  ground-based observations, but just at the red edge derived from
  pulsation modeling. The pulsation models show γ Dor gravity modes
  driven by the convective blocking mechanism, with frequencies of 1-3
  cycles per day (11 to 33 μHz). However, gravity modes were not seen
  in Kepler data; one signal at 1.776 cycles per day (20.56 μHz) may
  be attributable to a faint, possibly background, binary.

---------------------------------------------------------
Title: Oscillation mode linewidths and heights of 23 main-sequence
    stars observed by Kepler (Corrigendum)
Authors: Appourchaux, T.; Antia, H. M.; Benomar, O.; Campante, T. L.;
   Davies, G. R.; Handberg, R.; Howe, R.; Régulo, C.; Belkacem, K.;
   Houdek, G.; García, R. A.; Chaplin, W. J.
2016A&A...595C...2A    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The Asteroseismic Potential of TESS: Exoplanet-host Stars
Authors: Campante, T. L.; Schofield, M.; Kuszlewicz, J. S.; Bouma,
   L.; Chaplin, W. J.; Huber, D.; Christensen-Dalsgaard, J.; Kjeldsen,
   H.; Bossini, D.; North, T. S. H.; Appourchaux, T.; Latham, D. W.;
   Pepper, J.; Ricker, G. R.; Stassun, K. G.; Vanderspek, R.; Winn, J. N.
2016ApJ...830..138C    Altcode: 2016arXiv160801138C
  New insights on stellar evolution and stellar interior physics are
  being made possible by asteroseismology. Throughout the course of the
  Kepler mission, asteroseismology has also played an important role
  in the characterization of exoplanet-host stars and their planetary
  systems. The upcoming NASA Transiting Exoplanet Survey Satellite
  (TESS) will be performing a near all-sky survey for planets that
  transit bright nearby stars. In addition, its excellent photometric
  precision, combined with its fine time sampling and long intervals of
  uninterrupted observations, will enable asteroseismology of solar-type
  and red-giant stars. Here we develop a simple test to estimate the
  detectability of solar-like oscillations in TESS photometry of any given
  star. Based on an all-sky stellar and planetary synthetic population,
  we go on to predict the asteroseismic yield of the TESS mission,
  placing emphasis on the yield of exoplanet-host stars for which we
  expect to detect solar-like oscillations. This is done for both the
  target stars (observed at a 2-minute cadence) and the full-frame-image
  stars (observed at a 30-minute cadence). A similar exercise is also
  conducted based on a compilation of known host stars. We predict that
  TESS will detect solar-like oscillations in a few dozen target hosts
  (mainly subgiant stars but also in a smaller number of F dwarfs), in up
  to 200 low-luminosity red-giant hosts, and in over 100 solar-type and
  red-giant known hosts, thereby leading to a threefold improvement in the
  asteroseismic yield of exoplanet-host stars when compared to Kepler's.

---------------------------------------------------------
Title: Advances in the development of a Mach-Zehnder interferometric
    Doppler imager for seismology of giant planets
Authors: Gonçalves, Ivan; Schmider, François-Xavier; Bresson, Yves;
   Dejonghe, Julien; Preis, Olivier; Robbe-Dubois, Sylvie; Appourchaux,
   Thierry; Boumier, Patrick; Leclec'h, Jean-Christophe; Morinaud,
   Gilles; Gaulme, Patrick; Jackiewicz, Jason
2016SPIE.9908E..3MG    Altcode:
  The measurements of radial velocity fields on planets with a Doppler
  Spectro-Imager allow the study of atmospheric dynamics of giant planets
  and the detection of their acoustic oscillations. The frequencies of
  these oscillations lead to the determination of the internal structure
  by asteroseismology. A new imaging tachometer, based on a Mach-Zehnder
  interferometer, has been developed to monitor the Doppler shift of solar
  lines reflected at the surface of the planets. We present the principle
  of this instrument. A prototype was designed and built, following
  the specifications of a future space mission. The performance of the
  prototype, both at the laboratory and on the sky, is presented here.

---------------------------------------------------------
Title: Measuring the extent of convective cores in low-mass stars
using Kepler data: toward a calibration of core overshooting
Authors: Deheuvels, S.; Brandão, I.; Silva Aguirre, V.; Ballot, J.;
   Michel, E.; Cunha, M. S.; Lebreton, Y.; Appourchaux, T.
2016A&A...589A..93D    Altcode: 2016arXiv160302332D
  Context. Our poor understanding of the boundaries of convective
  cores generates large uncertainties on the extent of these cores and
  thus on stellar ages. The detection and precise characterization of
  solar-like oscillations in hundreds of main-sequence stars by CoRoT
  and Kepler has given the opportunity to revisit this problem. <BR />
  Aims: Our aim is to use asteroseismology to consistently measure the
  extent of convective cores in a sample of main-sequence stars whose
  masses lie around the mass limit for having a convective core. <BR />
  Methods: We first tested and validated a seismic diagnostic that was
  proposed to probe the extent of convective cores in a model-dependent
  way using the so-called r<SUB>010</SUB> ratios, which are built
  with l = 0 and l = 1 modes. We applied this procedure to 24 low-mass
  stars chosen among Kepler targets to optimize the efficiency of this
  diagnostic. For this purpose, we computed grids of stellar models
  with both the Cesam2k and mesa evolution codes, where the extensions
  of convective cores were modeled either by an instantaneous mixing or
  as a diffusion process. <BR /> Results: We found that 10 stars in our
  sample are in fact subgiants. Among the other targets, were able to
  unambiguously detect convective cores in eight stars, and we obtained
  seismic measurements of the extent of the mixed core in these targets
  with a good agreement between the Cesam2k and mesa codes. By performing
  optimizations using the Levenberg-Marquardt algorithm, we then obtained
  estimates of the amount of extra mixing beyond the core that is required
  in Cesam2k to reproduce seismic observations for these eight stars,
  and we showed that this can be used to propose a calibration of this
  quantity. This calibration depends on the prescription chosen for the
  extra mixing, but we found that it should also be valid for the code
  mesa, provided the same prescription is used. <BR /> Conclusions:
  This study constitutes a first step toward calibrating the extension
  of convective cores in low-mass stars, which will help reduce the
  uncertainties on the ages of these stars.

---------------------------------------------------------
Title: Helioseismology with Solar Orbiter
Authors: Löptien, Björn; Birch, Aaron C.; Gizon, Laurent; Schou,
   Jesper; Appourchaux, Thierry; Blanco Rodríguez, Julián; Cally,
   Paul S.; Dominguez-Tagle, Carlos; Gandorfer, Achim; Hill, Frank;
   Hirzberger, Johann; Scherrer, Philip H.; Solanki, Sami K.
2015SSRv..196..251L    Altcode: 2014arXiv1406.5435L; 2014SSRv..tmp...31L
  The Solar Orbiter mission, to be launched in July 2017, will
  carry a suite of remote sensing and in-situ instruments, including
  the Polarimetric and Helioseismic Imager (PHI). PHI will deliver
  high-cadence images of the Sun in intensity and Doppler velocity
  suitable for carrying out novel helioseismic studies. The orbit of
  the Solar Orbiter spacecraft will reach a solar latitude of up to
  21<SUP>∘</SUP> (up to 34<SUP>∘</SUP> by the end of the extended
  mission) and thus will enable the first local helioseismology studies of
  the polar regions. Here we consider an array of science objectives to be
  addressed by helioseismology within the baseline telemetry allocation
  (51 Gbit per orbit, current baseline) and within the science observing
  windows (baseline 3×10 days per orbit). A particularly important
  objective is the measurement of large-scale flows at high latitudes
  (rotation and meridional flow), which are largely unknown but play an
  important role in flux transport dynamos. For both helioseismology
  and feature tracking methods convection is a source of noise in
  the measurement of longitudinally averaged large-scale flows, which
  decreases as T <SUP>-1/2</SUP> where T is the total duration of the
  observations. Therefore, the detection of small amplitude signals (e.g.,
  meridional circulation, flows in the deep solar interior) requires long
  observation times. As an example, one hundred days of observations at
  lower spatial resolution would provide a noise level of about three m/s
  on the meridional flow at 80<SUP>∘</SUP> latitude. Longer time-series
  are also needed to study temporal variations with the solar cycle. The
  full range of Earth-Sun-spacecraft angles provided by the orbit will
  enable helioseismology from two vantage points by combining PHI with
  another instrument: stereoscopic helioseismology will allow the study
  of the deep solar interior and a better understanding of the physics
  of solar oscillations in both quiet Sun and sunspots. We have used a
  model of the PHI instrument to study its performance for helioseismology
  applications. As input we used a 6 hr time-series of realistic solar
  magneto-convection simulation (Stagger code) and the SPINOR radiative
  transfer code to synthesize the observables. The simulated power
  spectra of solar oscillations show that the instrument is suitable for
  helioseismology. In particular, the specified point spread function,
  image jitter, and photon noise are no obstacle to a successful mission.

---------------------------------------------------------
Title: Future Mission Concepts for Helioseismology
Authors: Sekii, Takashi; Appourchaux, Thierry; Fleck, Bernhard;
   Turck-Chièze, Sylvaine
2015SSRv..196..285S    Altcode: 2015SSRv..tmp...15S
  Future space-mission concepts currently discussed in the helioseismology
  community are reviewed. One popular idea is to observe the Sun from high
  latitudes, to explore the polar regions as well as to probe the deep
  interior using stereoscopic techniques, by combining observations from
  high latitudes with observations from within the ecliptic plane. Another
  idea is to stay within the ecliptic plane but still aim for stereoscopic
  helioseismology for deep layers. A new instrument and a novel mission
  concept for studying the solar core regions are also discussed.

---------------------------------------------------------
Title: A seismic and gravitationally bound double star observed by
    Kepler. Implication for the presence of a convective core
Authors: Appourchaux, T.; Antia, H. M.; Ball, W.; Creevey, O.;
   Lebreton, Y.; Verma, K.; Vorontsov, S.; Campante, T. L.; Davies,
   G. R.; Gaulme, P.; Régulo, C.; Horch, E.; Howell, S.; Everett, M.;
   Ciardi, D.; Fossati, L.; Miglio, A.; Montalbán, J.; Chaplin, W. J.;
   García, R. A.; Gizon, L.
2015A&A...582A..25A    Altcode:
  Context. Solar-like oscillations have been observed by Kepler and CoRoT
  in many solar-type stars, thereby providing a way to probe stars using
  asteroseismology. <BR /> Aims: The derivation of stellar parameters
  has usually been done with single stars. The aim of the paper is to
  derive the stellar parameters of a double-star system (HIP 93511),
  for which an interferometric orbit has been observed along with
  asteroseismic measurements. <BR /> Methods: We used a time series
  of nearly two years of data for the double star to detect the two
  oscillation-mode envelopes that appear in the power spectrum. Using
  a new scaling relation based on luminosity, we derived the radius and
  mass of each star. We derived the age of each star using two proxies:
  one based upon the large frequency separation and a new one based
  upon the small frequency separation. Using stellar modelling, the mode
  frequencies allowed us to derive the radius, the mass, and the age of
  each component. In addition, speckle interferometry performed since 2006
  has enabled us to recover the orbit of the system and the total mass
  of the system. <BR /> Results: From the determination of the orbit,
  the total mass of the system is 2.34<SUB>-0.33</SUB><SUP>+0.45</SUP>
  M<SUB>⊙</SUB>. The total seismic mass using scaling relations
  is 2.47 ± 0.07 M<SUB>⊙</SUB>. The seismic age derived using the
  new proxy based upon the small frequency separation is 3.5 ± 0.3
  Gyr. Based on stellar modelling, the mean common age of the system is
  2.7-3.9 Gyr. The mean total seismic mass of the system is 2.34-2.53
  M<SUB>⊙</SUB> consistent with what we determined independently
  with the orbit. The stellar models provide the mean radius, mass,
  and age of the stars as R<SUB>A</SUB> = 1.82-1.87R<SUB>⊙</SUB>,
  M<SUB>A</SUB> = 1.25-1.39 M<SUB>⊙</SUB>, Age<SUB>A</SUB> = 2.6-3.5
  Gyr; R<SUB>B</SUB> = 1.22-1.25 R<SUB>⊙</SUB>, M<SUB>B</SUB> =
  1.08-1.14 M<SUB>⊙</SUB>, Age<SUB>B</SUB> = 3.35-4.21 Gyr. The
  models provide two sets of values for Star A: [1.25-1.27]
  M<SUB>⊙</SUB> and [1.34-1.39] M<SUB>⊙</SUB>. We detect a
  convective core in Star A, while Star B does not have any. For the
  metallicity of the binary system of Z ≈ 0.02, we set the limit
  between stars having a convective core in the range [1.14-1.25]
  M<SUB>⊙</SUB>. <P />Appendices are available in electronic form at <A
  href="http://www.aanda.org/10.1051/0004-6361/201526610/olm">http://www.aanda.org</A>

---------------------------------------------------------
Title: The Polarimetric and Helioseismic Imager for Solar Orbiter:
    SO/PHI
Authors: Solanki, Sami K.; del Toro Iniesta, Jose Carlos; Woch,
   Joachim; Gandorfer, Achim; Hirzberger, Johann; Schmidt, Wolfgang;
   Appourchaux, Thierry; Alvarez-Herrero, Alberto
2015IAUS..305..108S    Altcode: 2015arXiv150203368S
  The Solar Orbiter is the next solar physics mission of the European
  Space Agency, ESA, in collaboration with NASA, with a launch planned in
  2018. The spacecraft is designed to approach the Sun to within 0.28 AU
  at perihelion of a highly eccentric orbit. The proximity with the Sun
  will also allow its observation at uniformly high resolution at EUV and
  visible wavelengths. Such observations are central for learning more
  about the magnetic coupling of the solar atmosphere. At a later phase
  in the mission the spacecraft will leave the ecliptic and study the
  enigmatic poles of the Sun from a heliographic latitude of up to 33°.

---------------------------------------------------------
Title: Asteroseismology of Solar-Type Stars with K2: Detection of
    Oscillations in C1 Data
Authors: Chaplin, W. J.; Lund, M. N.; Handberg, R.; Basu, S.;
   Buchhave, L. A.; Campante, T. L.; Davies, G. R.; Huber, D.; Latham,
   D. W.; Latham, C. A.; Serenelli, A.; Antia, H. M.; Appourchaux, T.;
   Ball, W. H.; Benomar, O.; Casagrande, L.; Christensen-Dalsgaard, J.;
   Coelho, H. R.; Creevey, O. L.; Elsworth, Y.; García, R. A.; Gaulme,
   P.; Hekker, S.; Kallinger, T.; Karoff, C.; Kawaler, S. D.; Kjeldsen,
   H.; Lundkvist, M. S.; Marcadon, F.; Mathur, S.; Miglio, A.; Mosser,
   B.; Régulo, C.; Roxburgh, I. W.; Silva Aguirre, V.; Stello, D.;
   Verma, K.; White, T. R.; Bedding, T. R.; Barclay, T.; Buzasi, D. L.;
   Dehuevels, S.; Gizon, L.; Houdek, G.; Howell, S. B.; Salabert, D.;
   Soderblom, D. R.
2015PASP..127.1038C    Altcode: 2015arXiv150701827C
  We present the first detections by the NASA K2 Mission of oscillations
  in solar-type stars, using short-cadence data collected during
  K2 Campaign\,1 (C1). We understand the asteroseismic detection
  thresholds for C1-like levels of photometric performance, and we
  can detect oscillations in subgiants having dominant oscillation
  frequencies around $1000\,\rm \mu Hz$. Changes to the operation of the
  fine-guidance sensors are expected to give significant improvements
  in the high-frequency performance from C3 onwards. A reduction in the
  excess high-frequency noise by a factor of two-and-a-half in amplitude
  would bring main-sequence stars with dominant oscillation frequencies as
  high as ${\simeq 2500}\,\rm \mu Hz$ into play as potential asteroseismic
  targets for K2.

---------------------------------------------------------
Title: Asteroseismic estimate of helium abundance of 16 Cyg A, B
Authors: Verma, Kuldeep; Faria, João P.; Antia, H. M.; Basu, Sarbani;
   Mazumdar, Anwesh; Monteiro, Mário J. P. F. G.; Appourchaux, Thierry;
   Chaplin, William J.; García, Rafael A.; Metcalfe, Travis S.
2015EPJWC.10106066V    Altcode:
  The helium ionization zone in a star leaves a characteristic signature
  on its oscillation frequencies, which can be used to estimate the
  helium content in the envelope of the star. We use the oscillation
  frequencies of 16 Cyg A and B, obtained using 2.5 years of Kepler data,
  to estimate the envelope helium abundance of these stars. We find the
  envelope helium abundance to lie in the range 0.231-0.251 for 16 Cyg
  A and 0.218-0.266 for 16 Cyg B.

---------------------------------------------------------
Title: An attempt to calibrate core overshooting using the seismic
    properties of low-mass stars
Authors: Deheuvels, S.; Silva Aguirre, V.; Cunha, M. S.; Appourchaux,
   T.; Ballot, J.; Brandão, I.; Lebreton, Y.; Michel, E.
2015EPJWC.10101013D    Altcode:
  The sizes of stellar convective cores remain uncertain because of our
  poor understanding of the interface between convective and radiative
  zones. The very high precision of the seismic data provided by the CoRoT
  and Kepler space missions offers a great opportunity to search for the
  signature of convective cores in main-sequence stars. We here validate
  the seismic diagnostic based on the r<SUB>010</SUB> ratios, which has
  been proposed to probe the size of convective cores, and we use it on
  a sample of 24 specially chosen Kepler targets. We thus constrain the
  extension of the core in 14 targets and find a tendency of the core
  extension to increase with stellar mass in this mass range. These
  results will be presented in more detail in a paper in preparation.

---------------------------------------------------------
Title: Helioseismology: Observations and space missions
Authors: Pallé, P. L.; Appourchaux, T.; Christensen-Dalsgaard, J.;
   Garcxía, I. A.
2015exse.book...25P    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Asteroseismology observations and space missions
Authors: Appourchaux, T.; Grundahl, F.
2015exse.book...11A    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Asteroseismic inference on rotation, gyrochronology and
    planetary system dynamics of 16 Cygni
Authors: Davies, G. R.; Chaplin, W. J.; Farr, W. M.; García, R. A.;
   Lund, M. N.; Mathis, S.; Metcalfe, T. S.; Appourchaux, T.; Basu, S.;
   Benomar, O.; Campante, T. L.; Ceillier, T.; Elsworth, Y.; Handberg,
   R.; Salabert, D.; Stello, D.
2015MNRAS.446.2959D    Altcode: 2014arXiv1411.1359D
  The solar analogues 16 Cyg A and B are excellent asteroseismic targets
  in the Kepler field of view and together with a red dwarf and a Jovian
  planet form an interesting system. For these more evolved Sun-like
  stars we cannot detect surface rotation with the current Kepler
  data but instead use the technique of asteroseimology to determine
  rotational properties of both 16 Cyg A and B. We find the rotation
  periods to be 23.8^{+1.5}_{-1.8} and 23.2^{+11.5}_{-3.2} d, and
  the angles of inclination to be 56^{+6}_{-5}° and 36^{+17}_{-7}°,
  for A and B, respectively. Together with these results we use the
  published mass and age to suggest that, under the assumption of a
  solar-like rotation profile, 16 Cyg A could be used when calibrating
  gyrochronology relations. In addition, we discuss the known 16 Cyg B
  star-planet eccentricity and measured low obliquity which is consistent
  with Kozai cycling and tidal theory.

---------------------------------------------------------
Title: Building galaxies, stars, planets and the ingredients for life
    between the stars. The science behind the European Ultraviolet-Visible
    Observatory
Authors: Gómez de Castro, Ana I.; Appourchaux, Thierry; Barstow,
   Martin A.; Barthelemy, Mathieu; Baudin, Frederic; Benetti, Stefano;
   Blay, Pere; Brosch, Noah; Bunce, Emma; de Martino, Domitilla;
   Deharveng, Jean-Michel; Ferlet, Roger; France, Kevin; García, Miriam;
   Gänsicke, Boris; Gry, Cecile; Hillenbrand, Lynne; Josselin, Eric;
   Kehrig, Carolina; Lamy, Laurent; Lapington, Jon; Lecavelier des
   Etangs, Alain; LePetit, Frank; López-Santiago, Javier; Milliard,
   Bruno; Monier, Richard; Naletto, Giampiero; Nazé, Yael; Neiner,
   Coralie; Nichols, Jonathan; Orio, Marina; Pagano, Isabella; Peroux,
   Céline; Rauw, Gregor; Shore, Steven; Spaans, Marco; Tovmassian,
   Gagik; ud-Doula, Asif; Vilchez, José
2014Ap&SS.354..229G    Altcode: 2014Ap&SS.tmp..185G; 2013arXiv1306.3358G
  This contribution gathers the contents of the white paper submitted
  by the UV community to the Call issued by the European Space Agency
  in March 2013, for the definition of the L2 and L3 missions in the ESA
  science program. We outlined the key science that a large UV facility
  would make possible and the instrumentation to be implemented. The
  growth of luminous structures and the building blocks of life in the
  Universe began as primordial gas was processed in stars and mixed at
  galactic scales. The mechanisms responsible for this development are
  not well-understood and have changed over the intervening 13 billion
  years. To follow the evolution of matter over cosmic time, it is
  necessary to study the strongest (resonance) transitions of the most
  abundant species in the Universe. Most of them are in the ultraviolet
  (UV; 950 Å-3000 Å) spectral range that is unobservable from the
  ground. A versatile space observatory with UV sensitivity a factor
  of 50-100 greater than existing facilities will revolutionize our
  understanding of the Universe. Habitable planets grow in protostellar
  discs under ultraviolet irradiation, a by-product of the star-disk
  interaction that drives the physical and chemical evolution of discs
  and young planetary systems. The electronic transitions of the most
  abundant molecules are pumped by this UV field, providing unique
  diagnostics of the planet-forming environment that cannot be accessed
  from the ground. Earth's atmosphere is in constant interaction with
  the interplanetary medium and the solar UV radiation field. A 50-100
  times improvement in sensitivity would enable the observation of the
  key atmospheric ingredients of Earth-like exoplanets (carbon, oxygen,
  ozone), provide crucial input for models of biologically active worlds
  outside the solar system, and provide the phenomenological baseline
  to understand the Earth atmosphere in context.

---------------------------------------------------------
Title: The PLATO 2.0 mission
Authors: Rauer, H.; Catala, C.; Aerts, C.; Appourchaux, T.; Benz,
   W.; Brandeker, A.; Christensen-Dalsgaard, J.; Deleuil, M.; Gizon,
   L.; Goupil, M. -J.; Güdel, M.; Janot-Pacheco, E.; Mas-Hesse,
   M.; Pagano, I.; Piotto, G.; Pollacco, D.; Santos, Ċ.; Smith, A.;
   Suárez, J. -C.; Szabó, R.; Udry, S.; Adibekyan, V.; Alibert, Y.;
   Almenara, J. -M.; Amaro-Seoane, P.; Eiff, M. Ammler-von; Asplund, M.;
   Antonello, E.; Barnes, S.; Baudin, F.; Belkacem, K.; Bergemann, M.;
   Bihain, G.; Birch, A. C.; Bonfils, X.; Boisse, I.; Bonomo, A. S.;
   Borsa, F.; Brandão, I. M.; Brocato, E.; Brun, S.; Burleigh, M.;
   Burston, R.; Cabrera, J.; Cassisi, S.; Chaplin, W.; Charpinet, S.;
   Chiappini, C.; Church, R. P.; Csizmadia, Sz.; Cunha, M.; Damasso, M.;
   Davies, M. B.; Deeg, H. J.; Díaz, R. F.; Dreizler, S.; Dreyer, C.;
   Eggenberger, P.; Ehrenreich, D.; Eigmüller, P.; Erikson, A.; Farmer,
   R.; Feltzing, S.; de Oliveira Fialho, F.; Figueira, P.; Forveille,
   T.; Fridlund, M.; García, R. A.; Giommi, P.; Giuffrida, G.; Godolt,
   M.; Gomes da Silva, J.; Granzer, T.; Grenfell, J. L.; Grotsch-Noels,
   A.; Günther, E.; Haswell, C. A.; Hatzes, A. P.; Hébrard, G.; Hekker,
   S.; Helled, R.; Heng, K.; Jenkins, J. M.; Johansen, A.; Khodachenko,
   M. L.; Kislyakova, K. G.; Kley, W.; Kolb, U.; Krivova, N.; Kupka, F.;
   Lammer, H.; Lanza, A. F.; Lebreton, Y.; Magrin, D.; Marcos-Arenal,
   P.; Marrese, P. M.; Marques, J. P.; Martins, J.; Mathis, S.; Mathur,
   S.; Messina, S.; Miglio, A.; Montalban, J.; Montalto, M.; Monteiro,
   M. J. P. F. G.; Moradi, H.; Moravveji, E.; Mordasini, C.; Morel, T.;
   Mortier, A.; Nascimbeni, V.; Nelson, R. P.; Nielsen, M. B.; Noack,
   L.; Norton, A. J.; Ofir, A.; Oshagh, M.; Ouazzani, R. -M.; Pápics,
   P.; Parro, V. C.; Petit, P.; Plez, B.; Poretti, E.; Quirrenbach, A.;
   Ragazzoni, R.; Raimondo, G.; Rainer, M.; Reese, D. R.; Redmer, R.;
   Reffert, S.; Rojas-Ayala, B.; Roxburgh, I. W.; Salmon, S.; Santerne,
   A.; Schneider, J.; Schou, J.; Schuh, S.; Schunker, H.; Silva-Valio,
   A.; Silvotti, R.; Skillen, I.; Snellen, I.; Sohl, F.; Sousa, S. G.;
   Sozzetti, A.; Stello, D.; Strassmeier, K. G.; Švanda, M.; Szabó,
   Gy. M.; Tkachenko, A.; Valencia, D.; Van Grootel, V.; Vauclair,
   S. D.; Ventura, P.; Wagner, F. W.; Walton, N. A.; Weingrill, J.;
   Werner, S. C.; Wheatley, P. J.; Zwintz, K.
2014ExA....38..249R    Altcode: 2014ExA...tmp...41R; 2013arXiv1310.0696R
  PLATO 2.0 has recently been selected for ESA's M3 launch opportunity
  (2022/24). Providing accurate key planet parameters (radius, mass,
  density and age) in statistical numbers, it addresses fundamental
  questions such as: How do planetary systems form and evolve? Are there
  other systems with planets like ours, including potentially habitable
  planets? The PLATO 2.0 instrument consists of 34 small aperture
  telescopes (32 with 25 s readout cadence and 2 with 2.5 s candence)
  providing a wide field-of-view (2232 deg <SUP>2</SUP>) and a large
  photometric magnitude range (4-16 mag). It focusses on bright (4-11
  mag) stars in wide fields to detect and characterize planets down to
  Earth-size by photometric transits, whose masses can then be determined
  by ground-based radial-velocity follow-up measurements. Asteroseismology
  will be performed for these bright stars to obtain highly accurate
  stellar parameters, including masses and ages. The combination of
  bright targets and asteroseismology results in high accuracy for
  the bulk planet parameters: 2 %, 4-10 % and 10 % for planet radii,
  masses and ages, respectively. The planned baseline observing strategy
  includes two long pointings (2-3 years) to detect and bulk characterize
  planets reaching into the habitable zone (HZ) of solar-like stars
  and an additional step-and-stare phase to cover in total about 50 %
  of the sky. PLATO 2.0 will observe up to 1,000,000 stars and detect
  and characterize hundreds of small planets, and thousands of planets
  in the Neptune to gas giant regime out to the HZ. It will therefore
  provide the first large-scale catalogue of bulk characterized planets
  with accurate radii, masses, mean densities and ages. This catalogue
  will include terrestrial planets at intermediate orbital distances,
  where surface temperatures are moderate. Coverage of this parameter
  range with statistical numbers of bulk characterized planets is unique
  to PLATO 2.0. The PLATO 2.0 catalogue allows us to e.g.: - complete
  our knowledge of planet diversity for low-mass objects, - correlate the
  planet mean density-orbital distance distribution with predictions from
  planet formation theories,- constrain the influence of planet migration
  and scattering on the architecture of multiple systems, and - specify
  how planet and system parameters change with host star characteristics,
  such as type, metallicity and age. The catalogue will allow us to study
  planets and planetary systems at different evolutionary phases. It
  will further provide a census for small, low-mass planets. This will
  serve to identify objects which retained their primordial hydrogen
  atmosphere and in general the typical characteristics of planets
  in such low-mass, low-density range. Planets detected by PLATO 2.0
  will orbit bright stars and many of them will be targets for future
  atmosphere spectroscopy exploring their atmosphere. Furthermore,
  the mission has the potential to detect exomoons, planetary rings,
  binary and Trojan planets. The planetary science possible with PLATO
  2.0 is complemented by its impact on stellar and galactic science via
  asteroseismology as well as light curves of all kinds of variable stars,
  together with observations of stellar clusters of different ages. This
  will allow us to improve stellar models and study stellar activity. A
  large number of well-known ages from red giant stars will probe the
  structure and evolution of our Galaxy. Asteroseismic ages of bright
  stars for different phases of stellar evolution allow calibrating
  stellar age-rotation relationships. Together with the results of ESA's
  Gaia mission, the results of PLATO 2.0 will provide a huge legacy to
  planetary, stellar and galactic science.

---------------------------------------------------------
Title: Filtergraph Calibration for the Polarimetric and Helioseismic
    Imager
Authors: Dominguez-Tagle, Carlos; Appourchaux, Thierry; Fourmond,
   Jean-Jacques; Philippon, Anne; Le Clec'h, Jean-Christophe; Bouzit,
   Mehdi; Le Cocguen, Regis
2014JSAST..12.Tk25D    Altcode:
  Solar Orbiter mission will study the Sun to the proximity of 0.28 AU,
  reaching solar latitudes up to 34°. This spacecraft will be launched
  in 2017 and will represent a complete approach to heliophysics. The
  Polarimetric and Helioseismic Imager (PHI), on board of Solar Orbiter,
  will provide the most important data for helioseismology. PHI will
  measure the photospheric vector magnetic field and the line-of-sight
  velocity observing the FeI 6173 A absorption line with a narrowband
  filtergraph (FG). At different spectral positions, the polarization
  state of the incoming light will be analyzed. The FG will provide a
  tuning range to compensate the spacecraft radial velocity and to scan
  the continuum at both sides of the absorption line. Thus, the fine
  tuning of the FG is essential for the instrument performance. Here
  we present the FG characterization and calibration status as they
  represent an important milestone in the development of the instrument.

---------------------------------------------------------
Title: Optical characterization of the breadboard narrowband
    prefilters for Solar Orbiter PHI
Authors: Dominguez-Tagle, Carlos; Appourchaux, Thierry; Ruiz
   de Galarreta, Claudia; Fourmond, Jean-Jacques; Philippon, Anne;
   Le Clec'h, Jean-Christophe; Bouzit, Mehdi; Bommier, Véronique;
   Le Cocguen, Regis; Crussaire, Daniel; Malherbe, Jean-Marie
2014SPIE.9143E..5GD    Altcode:
  The Polarimetric and Helioseismic Imager (PHI) on board of Solar
  Orbiter will observe the Sun to measure the photospheric vector
  magnetic field and the line-of-sight velocity. It will employ
  a narrowband filtergraph (FG) to scan the FeI 6173 Å absorption
  line. At different spectral positions, the polarization state of the
  incoming light will be analyzed. The FG will provide a tuning range
  to scan the line, the continuum, and to compensate for the spacecraft
  radial velocity, as it will approach to the Sun down to 0.28 AU. The
  FG includes a Fabry-Perot etalon and two narrowband prefilters. The
  bandpass of the narrowest one has a nominal Full Width at Half Maximum
  (FWHM) of 2.7 Å. The measurement of the prefilters characteristics is
  essential for the instrument calibration. Here we present the results
  of the breadboard prefilters characterization, which is an important
  milestone in the development of the instrument.

---------------------------------------------------------
Title: Asteroseismic Estimate of Helium Abundance of a Solar Analog
    Binary System
Authors: Verma, Kuldeep; Faria, João P.; Antia, H. M.; Basu, Sarbani;
   Mazumdar, Anwesh; Monteiro, Mário J. P. F. G.; Appourchaux, Thierry;
   Chaplin, William J.; García, Rafael A.; Metcalfe, Travis S.
2014ApJ...790..138V    Altcode: 2014arXiv1405.7512V
  16 Cyg A and B are among the brightest stars observed by Kepler. What
  makes these stars more interesting is that they are solar analogs. 16
  Cyg A and B exhibit solar-like oscillations. In this work we use
  oscillation frequencies obtained using 2.5 yr of Kepler data to
  determine the current helium abundance of these stars. For this we
  use the fact that the helium ionization zone leaves a signature on
  the oscillation frequencies and that this signature can be calibrated
  to determine the helium abundance of that layer. By calibrating the
  signature of the helium ionization zone against models of known helium
  abundance, the helium abundance in the envelope of 16 Cyg A is found
  to lie in the range of 0.231 to 0.251 and that of 16 Cyg B lies in
  the range of 0.218 to 0.266.

---------------------------------------------------------
Title: Oscillation mode linewidths and heights of 23 main-sequence
    stars observed by Kepler
Authors: Appourchaux, T.; Antia, H. M.; Benomar, O.; Campante, T. L.;
   Davies, G. R.; Handberg, R.; Howe, R.; Régulo, C.; Belkacem, K.;
   Houdek, G.; García, R. A.; Chaplin, W. J.
2014A&A...566A..20A    Altcode: 2014arXiv1403.7046A
  Context. Solar-like oscillations have been observed by Kepler and
  CoRoT in many solar-type stars, thereby providing a way to probe
  the stars using asteroseismology. <BR /> Aims: We provide the mode
  linewidths and mode heights of the oscillations of various stars as
  a function of frequency and of effective temperature. <BR /> Methods:
  We used a time series of nearly two years of data for each star. The
  23 stars observed belong to the simple or F-like category. The power
  spectra of the 23 main-sequence stars were analysed using both maximum
  likelihood estimators and Bayesian estimators, providing individual mode
  characteristics such as frequencies, linewidths, and mode heights. We
  study the source of systematic errors in the mode linewidths and mode
  heights, and we present a way to correct these errors with respect to
  a common reference fit. <BR /> Results: Using the correction, we can
  explain all sources of systematic errors, which could be reduced to
  less than ±15% for mode linewidths and heights, and less than ±5%
  for amplitude, when compared to the reference fit. The effect of
  a different estimated stellar background and a different estimated
  splitting will provide frequency-dependent systematic errors that
  might affect the comparison with theoretical mode linewidth and mode
  height, therefore affecting the understanding of the physical nature of
  these parameters. All other sources of relative systematic errors are
  less dependent upon frequency. We also provide the dependence of the
  so-called linewidth dip in the middle of the observed frequency range as
  a function of effective temperature. We show that the depth of the dip
  decreases with increasing effective temperature. The dependence of the
  dip on effective temperature may imply that the mixing length parameter
  α or the convective flux may increase with effective temperature. <P
  />Tables 4-27 and Appendices are available in electronic form at <A
  href="http://www.aanda.org/10.1051/0004-6361/201323317/olm">http://www.aanda.org</A>

---------------------------------------------------------
Title: Surface Activity and Oscillation Amplitudes of Red Giants in
    Eclipsing Binaries
Authors: Gaulme, P.; Jackiewicz, J.; Appourchaux, T.; Mosser, B.
2014ApJ...785....5G    Altcode: 2014arXiv1402.3027G
  Among the 19 red-giant stars belonging to eclipsing binary systems
  that have been identified in Kepler data, 15 display solar-like
  oscillations. We study whether the absence of mode detection in
  the remaining 4 is an observational bias or possibly evidence of
  mode damping that originates from tidal interactions. A careful
  analysis of the corresponding Kepler light curves shows that modes
  with amplitudes that are usually observed in red giants would have
  been detected if they were present. We observe that mode depletion is
  strongly associated with short-period systems, in which stellar radii
  account for 16%-24% of the semi-major axis, and where red-giant surface
  activity is detected. We suggest that when the rotational and orbital
  periods synchronize in close binaries, the red-giant component is spun
  up, so that a dynamo mechanism starts and generates a magnetic field,
  leading to observable stellar activity. Pressure modes would then be
  damped as acoustic waves dissipate in these fields.

---------------------------------------------------------
Title: Seismic analysis of HD 43587Aa, a solar-like oscillator in
    a multiple system
Authors: Boumier, P.; Benomar, O.; Baudin, F.; Verner, G.; Appourchaux,
   T.; Lebreton, Y.; Gaulme, P.; Chaplin, W.; García, R. A.; Hekker,
   S.; Regulo, C.; Salabert, D.; Stahn, T.; Elsworth, Y.; Gizon, L.;
   Hall, M.; Mathur, S.; Michel, E.; Morel, T.; Mosser, B.; Poretti,
   E.; Rainer, M.; Roxburgh, I.; do Nascimento, J. -D., Jr.; Samadi,
   R.; Auvergne, M.; Chaintreuil, S.; Baglin, A.; Catala, C.
2014A&A...564A..34B    Altcode: 2014arXiv1402.5053B
  Context. The object HD 43587Aa is a G0V star observed during the
  145-day LRa03 run of the COnvection, ROtation and planetary Transits
  space mission (CoRoT), for which complementary High Accuracy Radial
  velocity Planet Searcher (HARPS) spectra with S/N &gt; 300 were also
  obtained. Its visual magnitude is 5.71, and its effective temperature is
  close to 5950 K. It has a known companion in a highly eccentric orbit
  and is also coupled with two more distant companions. <BR /> Aims:
  We undertake a preliminary investigation of the internal structure
  of HD 43587Aa. <BR /> Methods: We carried out a seismic analysis of
  the star, using maximum likelihood estimators and Markov chain Monte
  Carlo methods. <BR /> Results: We established the first table of the
  eigenmode frequencies, widths, and heights for HD 43587Aa. The star
  appears to have a mass and a radius slightly larger than the Sun, and is
  slightly older (5.6 Gyr). Two scenarios are suggested for the geometry
  of the star: either its inclination angle is very low, or the rotation
  velocity of the star is very low. <BR /> Conclusions: A more detailed
  study of the rotation and of the magnetic and chromospheric activity for
  this star is needed, and will be the subject of a further study. New
  high resolution spectrometric observations should be performed for at
  least several months in duration.

---------------------------------------------------------
Title: Seismic constraints on the radial dependence of the internal
    rotation profiles of six Kepler subgiants and young red giants
Authors: Deheuvels, S.; Doğan, G.; Goupil, M. J.; Appourchaux, T.;
   Benomar, O.; Bruntt, H.; Campante, T. L.; Casagrande, L.; Ceillier,
   T.; Davies, G. R.; De Cat, P.; Fu, J. N.; García, R. A.; Lobel,
   A.; Mosser, B.; Reese, D. R.; Regulo, C.; Schou, J.; Stahn, T.;
   Thygesen, A. O.; Yang, X. H.; Chaplin, W. J.; Christensen-Dalsgaard,
   J.; Eggenberger, P.; Gizon, L.; Mathis, S.; Molenda-Żakowicz, J.;
   Pinsonneault, M.
2014A&A...564A..27D    Altcode: 2014arXiv1401.3096D
  Context. We still do not understand which physical mechanisms are
  responsible for the transport of angular momentum inside stars. The
  recent detection of mixed modes that contain the clear signature of
  rotation in the spectra of Kepler subgiants and red giants gives us
  the opportunity to make progress on this question. <BR /> Aims: Our
  aim is to probe the radial dependence of the rotation profiles for a
  sample of Kepler targets. For this purpose, subgiants and early red
  giants are particularly interesting targets because their rotational
  splittings are more sensitive to the rotation outside the deeper core
  than is the case for their more evolved counterparts. <BR /> Methods:
  We first extracted the rotational splittings and frequencies of the
  modes for six young Kepler red giants. We then performed a seismic
  modeling of these stars using the evolutionary codes Cesam2k and
  astec. By using the observed splittings and the rotational kernels
  of the optimal models, we inverted the internal rotation profiles
  of the six stars. <BR /> Results: We obtain estimates of the core
  rotation rates for these stars, and upper limits to the rotation in
  their convective envelope. We show that the rotation contrast between
  the core and the envelope increases during the subgiant branch. Our
  results also suggest that the core of subgiants spins up with time,
  while their envelope spins down. For two of the stars, we show that a
  discontinuous rotation profile with a deep discontinuity reproduces
  the observed splittings significantly better than a smooth rotation
  profile. Interestingly, the depths that are found to be most probable
  for the discontinuities roughly coincide with the location of the
  H-burning shell, which separates the layers that contract from those
  that expand. <BR /> Conclusions: We characterized the differential
  rotation pattern of six young giants with a range of metallicities, and
  with both radiative and convective cores on the main sequence. This will
  bring observational constraints to the scenarios of angular momentum
  transport in stars. Moreover, if the existence of sharp gradients in
  the rotation profiles of young red giants is confirmed, it is expected
  to help in distinguishing between the physical processes that could
  transport angular momentum in the subgiant and red giant branches. <P
  />Appendices and Tables 3-9 are available in electronic form at <A
  href="http://www.aanda.org/10.1051/0004-6361/201322779/olm">http://www.aanda.org</A>

---------------------------------------------------------
Title: The PLATO 2.0 Mission
Authors: Pagano, I.; Rauer, H.; Aerts, C.; Appourchaux, T.; Benz,
   W.; Brandeker, A.; Christensen-Dalsgaard, J.; Deleuil, M.; Gizon, L.;
   Goupil, M. -J.; Guedel, M.; Heras, A.; Janot-Pacheco, E.; Mas-Hesse,
   M.; Piotto, G.; Pollaco, D.; Ragazzoni, R.; Santos, N. C.; Smith,
   A.; Suarez, J. C.; Szabo, R.; Udry, S.
2014EPSC....9..789P    Altcode:
  PLATO 2.0 is the M class mission selected by ESA for its M3 launch
  slot in the framework of the Cosmic Vision 2015-2025 program. The main
  goals of PLATO 2.0 are the detection of terrestrial exoplanets in the
  habitable zone of solar-type stars and the characterization of their
  bulk properties needed to determine their habitability. Moreover,
  PLATO 2.0 will be key in understanding the formation, architecture,
  and evolution of planetary systems thanks to a thorough inventory
  of the physical properties of thousands of rocky, icy, and gaseous
  giant planets. We will illustrate the PLATO 2.0 science goals, how
  the instrument is conceived to fulfil the science requirements, and
  how the project is organized to implement the instrument, plan the
  observations, and exploit the resulting data.

---------------------------------------------------------
Title: Prospects for Detecting Asteroseismic Binaries in Kepler Data
Authors: Miglio, A.; Chaplin, W. J.; Farmer, R.; Kolb, U.; Girardi,
   L.; Elsworth, Y.; Appourchaux, T.; Handberg, R.
2014ApJ...784L...3M    Altcode: 2014arXiv1402.2480M
  Asteroseismology may in principle be used to detect unresolved stellar
  binary systems comprised of solar-type stars and/or red giants. This
  novel method relies on the detection of the presence of two solar-like
  oscillation spectra in the frequency spectrum of a single light
  curve. Here, we make predictions of the numbers of systems that may be
  detectable in data already collected by the NASA Kepler Mission. Our
  predictions, which are based upon TRILEGAL and BiSEPS simulations
  of the Kepler field of view, indicate that as many as 200 or more
  "asteroseismic binaries" may be detectable in this manner. Most
  of these binaries should be comprised of two He-core-burning red
  giants. Owing largely to the limited numbers of targets with the
  requisite short-cadence Kepler data, we expect only a small number of
  detected binaries containing solar-type stars. The predicted yield of
  detections is sensitive to the assumed initial mass ratio distribution
  (IMRD) of the binary components and therefore represents a sensitive
  calibration of the much debated IMRD near mass ratio unity.

---------------------------------------------------------
Title: A crash course on data analysis in asteroseismology
Authors: Appourchaux, Thierry
2014aste.book..123A    Altcode: 2011arXiv1103.5352A
  In this course, I try to provide a few basics required for performing
  data analysis in asteroseismology. First, I address how one can properly
  treat times series: the sampling, the filtering effect, the use of
  Fourier transform, the associated statistics. Second, I address how one
  can apply statistics for decision making and for parameter estimation
  either in a frequentist of a Bayesian framework. Last, I review how
  these basic principle have been applied (or not) in asteroseismology.

---------------------------------------------------------
Title: VizieR Online Data Catalog: Asteroseismic study of solar-type
    stars (Chaplin+, 2014)
Authors: Chaplin, W. J.; Basu, S.; Huber, D.; Serenelli, A.;
   Casagrande, L.; Silva Aguirre, V.; Ball, W. H.; Creevey, O. L.;
   Gizon, L.; Handberg, R.; Karoff, C.; Lutz, R.; Marques, J. P.;
   Miglio, A.; Stello, D.; Suran, M. D.; Pricopi, D.; Metcalfe, T. S.;
   Monteiro, M. J. P. F. G.; Molenda-Zakowicz, J.; Appourchaux, T.;
   Christensen-Dalsgaard, J.; Elsworth, Y.; Garcia, R. A.; Houdek, G.;
   Kjeldsen, H.; Bonanno, A.; Campante, T. L.; Corsaro, E.; Gaulme, P.;
   Hekker, S.; Mathur, S.; Mosser, B.; Regulo, C.; Salabert, D.
2014yCat..22100001C    Altcode:
  During the first 10 months of science operations more than 2000
  solar-type stars were selected by the Kepler Asteroseismic Science
  Consortium (KASC) to be observed as part of an asteroseismic survey
  of the Sun-like population in the Kepler field of view. Solar-like
  oscillations were detected by Kepler in more than 500 stars (Chaplin
  et al. 2011Sci...332..213C), and from these data robust global or
  average asteroseismic parameters were determined for all targets in the
  sample. These asteroseismic parameters allow us to estimate fundamental
  properties of the stars. In this paper we present stellar properties
  - namely masses, radii, surface gravities, mean densities and ages -
  of this asteroseismic sample of main-sequence and subgiant stars. <P
  />(5 data files).

---------------------------------------------------------
Title: Asteroseismic Fundamental Properties of Solar-type Stars
    Observed by the NASA Kepler Mission
Authors: Chaplin, W. J.; Basu, S.; Huber, D.; Serenelli, A.;
   Casagrande, L.; Silva Aguirre, V.; Ball, W. H.; Creevey, O. L.;
   Gizon, L.; Handberg, R.; Karoff, C.; Lutz, R.; Marques, J. P.;
   Miglio, A.; Stello, D.; Suran, M. D.; Pricopi, D.; Metcalfe, T. S.;
   Monteiro, M. J. P. F. G.; Molenda-Żakowicz, J.; Appourchaux, T.;
   Christensen-Dalsgaard, J.; Elsworth, Y.; García, R. A.; Houdek, G.;
   Kjeldsen, H.; Bonanno, A.; Campante, T. L.; Corsaro, E.; Gaulme, P.;
   Hekker, S.; Mathur, S.; Mosser, B.; Régulo, C.; Salabert, D.
2014ApJS..210....1C    Altcode: 2013arXiv1310.4001C
  We use asteroseismic data obtained by the NASA Kepler mission to
  estimate the fundamental properties of more than 500 main-sequence and
  sub-giant stars. Data obtained during the first 10 months of Kepler
  science operations were used for this work, when these solar-type
  targets were observed for one month each in survey mode. Stellar
  properties have been estimated using two global asteroseismic parameters
  and complementary photometric and spectroscopic data. Homogeneous sets
  of effective temperatures, T <SUB>eff</SUB>, were available for the
  entire ensemble from complementary photometry; spectroscopic estimates
  of T <SUB>eff</SUB> and [Fe/H] were available from a homogeneous
  analysis of ground-based data on a subset of 87 stars. We adopt
  a grid-based analysis, coupling six pipeline codes to 11 stellar
  evolutionary grids. Through use of these different grid-pipeline
  combinations we allow implicitly for the impact on the results of
  stellar model dependencies from commonly used grids, and differences
  in adopted pipeline methodologies. By using just two global parameters
  as the seismic inputs we are able to perform a homogenous analysis
  of all solar-type stars in the asteroseismic cohort, including many
  targets for which it would not be possible to provide robust estimates
  of individual oscillation frequencies (due to a combination of low
  signal-to-noise ratio and short dataset lengths). The median final
  quoted uncertainties from consolidation of the grid-based analyses
  are for the full ensemble (spectroscopic subset) approximately 10.8%
  (5.4%) in mass, 4.4% (2.2%) in radius, 0.017 dex (0.010 dex) in log g,
  and 4.3% (2.8%) in mean density. Around 36% (57%) of the stars have
  final age uncertainties smaller than 1 Gyr. These ages will be useful
  for ensemble studies, but should be treated carefully on a star-by-star
  basis. Future analyses using individual oscillation frequencies will
  offer significant improvements on up to 150 stars, in particular for
  estimates of the ages, where having the individual frequency data is
  most important.

---------------------------------------------------------
Title: On the development of a Fourier Transform Spectrometer for
    Solar Physics
Authors: Ruiz de Galarreta, Claudia; Vial, Jean-Claude; Appourchaux,
   Thierry; Philippon, Anne
2014cosp...40E2793R    Altcode:
  The origin and the evolution of the different structures that inhabit
  beyond the Sun’s photosphere, as well as the processes involved in
  the dynamics and the heating of the corona remain quite unknown. The
  inextricable complexity of the physical phenomena that govern the solar
  outer atmosphere is accompanied by the lack of suitable data adapted to
  the scientific need. Indeed, the interpretation and the models of the
  mechanisms that connect the exchanges between the chromosphere and the
  corona depend on critical observational parameters. It is for example
  essential to measure broad bands of vertical temperature and density
  ranges that fit the multiple spatial and temporal scales that are
  characteristic of the different events that take place in the Sun. The
  understanding of the dynamics of the plasma must be also based on the
  Doppler analysis of the observed scene. That implies the ability to
  combine time resolved spectroscopic and imaging technologies. Moreover,
  space is the place to observe the far UV corona and that implies a
  real technical challenge. Despite excellent advances in technology and
  instrumentation, the study of the Sun in the far UV is a fairly recent
  science. To date, no solar space mission could provide a combined and
  simultaneous diagnostic of both observables in the spectral range of
  interest. It is because of these expectations that the study of a
  new device called IFTSUV (the acronym of Imaging Fourier Transform
  Spectrometer working in the far UV) is presented in this paper. We
  start from the definition of the scientific requirements that lead to
  the technical choice, the first objective of this study is to develop
  a preliminary instrumental model of the IFTSUV. The overall technical
  and design specifications are based in theoretical calculations that
  have been expressed in terms of spectral accuracy, image quality and
  signal to noise ratio. Throughout the identification of difficult
  points, the realization of a servo-metrology system to control the
  sampling mirror appears naturally as an intrinsic need of proof of
  concept. Indeed, the wavenumbers from the raw spectra are set by the
  interferogram. That implies that acquisition must be rigorously constant
  and that the sampling steps must be known with high accuracy. Therefore,
  the mockup of a metrological solution that has been developped at IAS
  will is also presented. The results on the damonstrator that validate
  and converge to the optimization and prototyping of a system that could
  be integrated in a space based application will be discussed. Finally we
  propose a discussion on the possible future space mission opportunities
  in which this innovative project could be framed.

---------------------------------------------------------
Title: The History of the g-mode Quest
Authors: Appourchaux, T.; Pallé, P. L.
2013ASPC..478..125A    Altcode: 2013arXiv1309.3835A
  The quest for the solar gravity modes (or g modes) is key for the
  understanding of the structure and dynamics of the solar core. We
  review the history of the solar g-mode searches which is separated in
  three nearly distinct eras which correspond to: the theory of g modes,
  the search from the ground and the search from space. The prospects
  of definitive solar g-mode detection are also discussed.

---------------------------------------------------------
Title: The JOVIAL Project for Jovian Seismology
Authors: Schmider, F. X.; Appourchaux, T.; Gaulme, P.; Guillot, T.;
   Sato, B.; Murphy, N.; Daban, J. B.; Gay, J.; Soulat, L.; Baudin,
   F.; Boumier, P.; Ollivier, M.; Bordé. P.; Jackiewicz, J.; Ida, S.;
   Showman, A. P.
2013ASPC..478..119S    Altcode:
  Jovian seismology is a unique tool to determine the internal structure
  of the giant planet. It could uncover the size and mass of the core,
  if any, the existence of a “plasma phase transition” between the
  molecular and the metallic hydrogen envelope, reveal the internal
  dynamic, and more generally address the formation and evolution of
  giant planets in the solar system giving a point of comparison for extra
  solar planets. Jovian seismology requires special observing tool. SYMPA
  (Schmider et al. 2007; Gaulme et al. 2008) was the first project
  specially designed for those objectives. A new type of instrument,
  a Doppler Imager, had been developed. The project permitted for the
  first time the measurement of the fundamental acoustic frequency
  of Jupiter (Gaulme et al. 2011). It also validated the principle
  of the instrument. However, several limitations appeared during the
  observations. The main one was the poor temporal coverage. A new version
  of the Doppler Spectro Imager (DSI) has been studied extensively in
  the framework of the development of a space instrument for the JUICE
  mission. A prototype of this new device is presently developed in the
  laboratory (Soulat et al. 2011) and shows excellent sensitivity and
  stability. It will be tested on the sky in January 2014. The JOVIAL
  project foresees the installation of three similar instruments on
  three telescopes around the Earth (Japan, France, and USA) that will
  provide the necessary continuity in the observations. We expect to
  observe winds in the Jovian atmosphere with a precision better than
  2 m/s and to detect modes with amplitude as low as 5 cm/s up to the
  degree ℓ = 10 at least. The main objective of the project is the
  detection of the Jovian core.

---------------------------------------------------------
Title: Asteroseismology observations and space missions
Authors: Appourchaux, T.; Grundahl, F.
2013arXiv1312.6993A    Altcode:
  Contribution to a book entitled "Extraterrestrial seismology".

---------------------------------------------------------
Title: Mode Line Widths in Red-Giant Stars
Authors: Baudin, F.; Elsworth, Y.; Hekker, S.; Kallinger, T.; Stello,
   D.; Mosser, B.; Appourchaux, T.; Belkacem, K.; Benomar, O.; Barban,
   C.; Chaplin, W. J.
2013ASPC..479..179B    Altcode:
  Mode line widths and amplitudes provide valuable information on stellar
  oscillation excitation and damping, and thus on physical processes such
  as convection, radiative losses and convection/pulsation coupling. We
  present preliminary results for mode line widths obtained by fitting
  mode spectra from Kepler observations. The difficulties of such fitting
  are discussed as well as these preliminary estimates in the context
  of models.

---------------------------------------------------------
Title: Kepler White Paper: Asteroseismology of Solar-Like Oscillators
    in a 2-Wheel Mission
Authors: Chaplin, W. J; Kjeldsen, H.; Christensen-Dalsgaard, J.;
   Gilliland, R. L.; Kawaler, S. D.; Basu, S.; De Ridder, J.; Huber, D.;
   Arentoft, T.; Schou, J.; Garcia, R. A.; Metcalfe, T. S.; Brogaard, K.;
   Campante, T. L.; Elsworth, Y.; Miglio, A.; Appourchaux, T.; Bedding,
   T. R.; Hekker, S.; Houdek, G.; Karoff, C.; Molenda-Zakowicz, J.;
   Monteiro, M. J. P. F. G.; Silva Aguirre, V.; Stello, D.; Ball, W.;
   Beck, P. G.; Birch, A. C.; Buzasi, D. L.; Casagrande, L.; Cellier,
   T.; Corsaro, E.; Creevey, O. L.; Davies, G. R.; Deheuvels, S.; Dogan,
   G.; Gizon, L.; Grundahl, F.; Guzik, J.; Handberg, R.; Jimenez, A.;
   Kallinger, T.; Lund, M. N.; Lundkvist, M.; Mathis, S.; Mathur, S.;
   Mazumdar, A.; Mosser, B.; Neiner, C.; Nielsen, M. B.; Palle, P. L.;
   Pinsonneault, M. H.; Salabert, D.; Serenelli, A. M.; Shunker, H.;
   White, T. R.
2013arXiv1309.0702C    Altcode:
  We comment on the potential for continuing asteroseismology of
  solar-type and red-giant stars in a 2-wheel Kepler Mission. Our main
  conclusion is that by targeting stars in the ecliptic it should be
  possible to perform high-quality asteroseismology, as long as favorable
  scenarios for 2-wheel pointing performance are met. Targeting the
  ecliptic would potentially facilitate unique science that was not
  possible in the nominal Mission, notably from the study of clusters
  that are significantly brighter than those in the Kepler field. Our
  conclusions are based on predictions of 2-wheel observations made by
  a space photometry simulator, with information provided by the Kepler
  Project used as input to describe the degraded pointing scenarios. We
  find that elevated levels of frequency-dependent noise, consistent with
  the above scenarios, would have a significant negative impact on our
  ability to continue asteroseismic studies of solar-like oscillators in
  the Kepler field. However, the situation may be much more optimistic
  for observations in the ecliptic, provided that pointing resets of the
  spacecraft during regular desaturations of the two functioning reaction
  wheels are accurate at the &lt; 1 arcsec level. This would make it
  possible to apply a post-hoc analysis that would recover most of the
  lost photometric precision. Without this post-hoc correction---and the
  accurate re-pointing it requires---the performance would probably be
  as poor as in the Kepler-field case. Critical to our conclusions for
  both fields is the assumed level of pointing noise (in the short-term
  jitter and the longer-term drift). We suggest that further tests will
  be needed to clarify our results once more detail and data on the
  expected pointing performance becomes available, and we offer our
  assistance in this work.

---------------------------------------------------------
Title: Seismic constraints on rotation of Sun-like star and mass
    of exoplanet
Authors: Gizon, L.; Ballot, J.; Michel, E.; Stahn, T.; Vauclair, G.;
   Bruntt, H.; Quirion, P. -O.; Benomar, O.; Vauclair, S.; Appourchaux,
   T.; Auvergne, M.; Baglin, A.; Barban, C.; Baudin, F.; Bazot, M.;
   Campante, T.; Catala, C.; Chaplin, W.; Creevey, O.; Deheuvels, S.;
   Dolez, N.; Elsworth, Y.; Garcia, R.; Gaulme, P.; Mathis, S.; Mathur,
   S.; Mosser, B.; Regulo, C.; Roxburgh, I.; Salabert, D.; Samadi, R.;
   Sato, K.; Verner, G.; Hanasoge, S.; Sreenivasan, K. R.
2013PNAS..11013267G    Altcode: 2013arXiv1308.4352G
  Rotation is thought to drive cyclic magnetic activity in the Sun
  and Sun-like stars. Stellar dynamos, however, are poorly understood
  owing to the scarcity of observations of rotation and magnetic fields
  in stars. Here, inferences are drawn on the internal rotation of a
  distant Sun-like star by studying its global modes of oscillation. We
  report asteroseismic constraints imposed on the rotation rate and the
  inclination of the spin axis of the Sun-like star HD 52265, a principal
  target observed by the CoRoT satellite that is known to host a planetary
  companion. These seismic inferences are remarkably consistent with an
  independent spectroscopic observation (rotational line broadening)
  and with the observed rotation period of star spots. Furthermore,
  asteroseismology constrains the mass of exoplanet HD 52265b. Under
  the standard assumption that the stellar spin axis and the axis of the
  planetary orbit coincide, the minimum spectroscopic mass of the planet
  can be converted into a true mass of 1.85 (+0.52,-0.42) M_Jupiter,
  which implies that it is a planet, not a brown dwarf.

---------------------------------------------------------
Title: Filtergraph Calibration for the Polarimetric and Helioseismic
    Imager
Authors: Dominguez-Tagle, Carlos; Appourchaux, Thierry; Fourmond,
   Jean-Jacques; Philippon, Anne; Le Clec'h, Jean-Christophe; Bouzit,
   Mehdi; Le Cocguen, Regis
2013ists.conf...46D    Altcode:
  ESA's Solar Orbiter mission will study the Sun to the proximity
  of 0.28 AU, reaching solar latitudes up to 34deg. This spacecraft
  will be launched in 2017 and will represent a complete approach
  to heliophysics. The Polarimetric and Helioseismic Imager (PHI),
  on board of Solar Orbiter, will provide the most important data for
  helioseismology. PHI will measure the photospheric vector magnetic field
  and the line-of-sight velocity observing the FeI 6173A absorption line
  with a narrowband filtergraph (FG). At different spectral positions,
  the polarisation state of the incoming light will be analysed. The FG
  will provide a tuning range to compensate the spacecraft radial velocity
  and to scan the continuum at both sides the absorption line. Thus, the
  fine tuning of the FG is essential for the instrument performance. Here
  we present the FG characterisation and calibration status as they
  represent an important milestone in the development of the instrument.

---------------------------------------------------------
Title: Helioseismology with PICARD
Authors: Corbard, T.; Salabert, D.; Boumier, P.; Appourchaux, T.;
   Hauchecorne, A.; Journoud, P.; Nunge, A.; Gelly, B.; Hochedez, J. F.;
   Irbah, A.; Meftah, M.; Renaud, C.; Turck-Chièze, S.
2013JPhCS.440a2025C    Altcode: 2013arXiv1301.6940C
  PICARD is a CNES micro-satellite launched in June 2010 [17]. Its main
  goal is to measure the solar shape, total and spectral irradiance during
  the ascending phase of the activity cycle. The SODISM telescope onboard
  PICARD also allows us to conduct a program for helioseismology in
  intensity at 535.7 nm [5]. One-minute cadence low-resolution full images
  are available for a so-called medium-l program, and high-resolution
  images of the limb recorded every 2 minutes are used to study mode
  amplification near the limb in the perspective of g-mode search. First
  analyses and results from these two programs are presented here.

---------------------------------------------------------
Title: Stellar Ages and Convective Cores in Field Main-sequence Stars:
    First Asteroseismic Application to Two Kepler Targets
Authors: Silva Aguirre, V.; Basu, S.; Brandão, I. M.;
   Christensen-Dalsgaard, J.; Deheuvels, S.; Doğan, G.; Metcalfe, T. S.;
   Serenelli, A. M.; Ballot, J.; Chaplin, W. J.; Cunha, M. S.; Weiss,
   A.; Appourchaux, T.; Casagrande, L.; Cassisi, S.; Creevey, O. L.;
   García, R. A.; Lebreton, Y.; Noels, A.; Sousa, S. G.; Stello, D.;
   White, T. R.; Kawaler, S. D.; Kjeldsen, H.
2013ApJ...769..141S    Altcode: 2013arXiv1304.2772S
  Using asteroseismic data and stellar evolution models we obtain the
  first detection of a convective core in a Kepler field main-sequence
  star, putting a stringent constraint on the total size of the mixed
  zone and showing that extra mixing beyond the formal convective
  boundary exists. In a slightly less massive target the presence of
  a convective core cannot be conclusively discarded, and thus its
  remaining main-sequence lifetime is uncertain. Our results reveal
  that best-fit models found solely by matching individual frequencies
  of oscillations corrected for surface effects do not always properly
  reproduce frequency combinations. Moreover, slightly different criteria
  to define what the best-fit model is can lead to solutions with similar
  global properties but very different interior structures. We argue that
  the use of frequency ratios is a more reliable way to obtain accurate
  stellar parameters, and show that our analysis in field main-sequence
  stars can yield an overall precision of 1.5%, 4%, and 10% in radius,
  mass, and age, respectively. We compare our results with those obtained
  from global oscillation properties, and discuss the possible sources of
  uncertainties in asteroseismic stellar modeling where further studies
  are still needed.

---------------------------------------------------------
Title: Mode lifetime and associated scaling relations
Authors: Belkacem, K.; Appourchaux, T.; Baudin, F.; Dupret, M. A.;
   Goupil, M. J.; Marques, J. P.; Noels, A.; Samadi, R.
2013EPJWC..4303009B    Altcode:
  Thanks to the CoRoT and Kepler spacecrafts, scaling relations (linking
  seismic indices and global stellar parameters) are becoming the
  cornerstone of ensemble asteroseismology. Among them, the relation
  between the cut-off frequency and the frequency of the maximum in
  the power spectrum of solar-like pulsators as well as the relation
  between mode lifetime and the effective temperature remain poorly
  understood. However, a solid theoretical background is essential
  to assess the accuracy of those relations and subsequently of the
  derived stellar parameters. We will thus present recent advances on the
  understanding of the underlying mechanisms governing those relations
  and show that the physics of mode lifetime (thus of mode damping)
  plays a major role.

---------------------------------------------------------
Title: VizieR Online Data Catalog: Abundances of 93 solar-type Kepler
    targets (Bruntt+, 2012)
Authors: Bruntt, H.; Basu, S.; Smalley, B.; Chaplin, W. J.; Verner,
   G. A.; Bedding, T. R.; Catala, C.; Gazzano, J. -C.; Molenda-Zakowicz,
   J.; Thygesen, A. O.; Uytterhoeven, K.; Hekker, S.; Huber, D.; Karoff,
   C.; Mathur, S.; Mosser, B.; Appourchaux, T.; Campante, T. L.; Elsworth,
   Y.; Garcia, R. A.; Handberg, R.; Metcalfe, T. S.; Quirion, P. -O.;
   Regulo, C.; Roxburgh, I. W.; Stello, D.; Christensen-Dalsgaard,
   J.; Kawaler, S. D.; Kjeldsen, H.; Morris, R. L.; Quintana, E. V.;
   Sanderfer, D. T.
2013yCat..74230122B    Altcode:
  The spectra were obtained with the ESPaDOnS spectrograph at the 3.6-m
  Canada-France-Hawaii Telescope (CFHT) in USA and with the NARVAL
  spectrograph mounted on the 2-m Bernard Lyot Telescope at the Pic du
  Midi Observatory in France. In both the facilities, the observations
  were carried out as service observations from May to September in
  2010. <P />(3 data files).

---------------------------------------------------------
Title: Metrology for a solar imaging Fourier transform spectrometer
working in the far UV: from the instrumental concept to the first
    experimental results
Authors: Ruiz de Galarreta Fanjul, C.; Bouzit, M.; Appourchaux, T.;
   Dassas, K.; Viale, T.; Philippon, A.; Vial, J. -C.; Maillard, J. -P.
2012SPIE.8450E..0DR    Altcode:
  The spectroscopy of the far UV emission lines of the solar spectrum
  combined with an imaging capability is essential to understand the
  physics of the outer solar atmosphere. An imaging Fourier transform
  spectrometer (IFTSUV) is an attractive instrumental solution to perform
  such far-UV solar observations. Working in the far UV involves high
  precision metrology to maintain the optical path difference (OPD) during
  the entire scanning process of the interferogram. It also involves
  a compact all-reflection design for UV applications. We present
  the specification of a servo-system that enables dynamic tip/tilt
  alignment compensation and OPD sampling measurement of the IFTSUV
  scanning mirror. We also discuss the first experimental results of a
  breadboard as well as the preliminary design of a space-based device.

---------------------------------------------------------
Title: Echoes: a new instrumental concept of spectro-imaging for
    Jovian seismology
Authors: Soulat, L.; Schmider, F. -X.; Robbe-Dubois, S.; Appourchaux,
   T.; Bresson, Y.; Daban, J. -B.; Gaulme, P.; Gay, J.; Gouvret, C.
2012SPIE.8442E..4MS    Altcode:
  Echoes is a project of a space-borne instrument which has been proposed
  as part of the JUICE mission which is selected in the Cosmic Vision
  program of the European Space Agency (ESA) to perform seismic and
  dynamics studies of Jupiter's interior and atmosphere. Based on an
  original Mach-Zehnder design, the instrument aims to measure Doppler
  shifts of solar spectral lines, which are reflected by cloud layers
  of Jupiter's upper troposphere, coupled with imaging capabilities. It
  is specified to detect global oscillations with degree up to l = 50
  and amplitude as low as 1 cm/s at the surface of Jupiter. In order
  to check the compliance of the instrument, and its capability to
  operate in representative environment (TRL5), we build a prototype to
  perform tests. In this paper, we present the prototype implemented
  at Observatoire de la Côte d'Azur in collaboration with Institut
  d'Astrophysique Spatiale. We describe the design of the Mach-Zehnder
  and the procedure of control and adjustment. We present the necessary
  tests and we show on simulation that the measurements will provide
  the required precision. In conclusion, we will explain the perspective
  for such a new instrument.

---------------------------------------------------------
Title: Seismic Analysis of Four Solar-like Stars Observed during
    More Than Eight Months by Kepler
Authors: Mathur, S.; Campante, T. L.; Handberg, R.; García, R. A.;
   Appourchaux, T.; Bedding, T. R.; Mosser, B.; Chaplin, W. J.; Ballot,
   J.; Benomar, O.; Bonanno, A.; Corsaro, E.; Gaulme, P.; Hekker,
   S.; Régulo, C.; Salabert, D.; Verner, G.; White, T. R.; Brandão,
   I. M.; Creevey, O. L.; Dogan, G.; Bazot, M.; Cunha, M. S.; Elsworth,
   Y.; Huber, D.; Hale, S. J.; Houdek, G.; Karoff, C.; Lundkvist, M.;
   Metcalfe, T. S.; Molenda-Zakowicz, J.; Monteiro, M. J. P. F. G.;
   Thompson, M. J.; Stello, D.; Christensen-Dalsgaard, J.; Gilliland,
   R. L.; Kawaler, S. D.; Kjeldsen, H.; Clarke, B. D.; Girouard, F. R.;
   Hall, J. R.; Quintana, E. V.; Sanderfer, D. T.; Seader, S. E.
2012ASPC..462..180M    Altcode: 2011arXiv1110.0135M
  Having started science operations in May 2009, the Kepler photometer
  has been able to provide exquisite data for solar-like stars. Five
  out of the 42 stars observed continuously during the survey phase
  show evidence of oscillations, even though they are rather faint
  (magnitudes from 10.5 to 12). In this paper, we present an overview
  of the results of the seismic analysis of 4 of these stars observed
  during more than eight months.

---------------------------------------------------------
Title: The EUI instrument on board the Solar Orbiter mission: from
    breadboard and prototypes to instrument model validation
Authors: Halain, J. -P.; Rochus, P.; Renotte, E.; Appourchaux, T.;
   Berghmans, D.; Harra, L.; Schühle, U.; Schmutz, W.; Auchère, F.;
   Zhukov, A.; Dumesnil, C.; Delmotte, F.; Kennedy, T.; Mercier, R.;
   Pfiffner, D.; Rossi, L.; Tandy, J.; BenMoussa, A.; Smith, P.
2012SPIE.8443E..07H    Altcode:
  The Solar Orbiter mission will explore the connection between the Sun
  and its heliosphere, taking advantage of an orbit approaching the Sun at
  0.28 AU. As part of this mission, the Extreme Ultraviolet Imager (EUI)
  will provide full-sun and high-resolution image sequences of the solar
  atmosphere at selected spectral emission lines in the extreme and vacuum
  ultraviolet. To achieve the required scientific performances under the
  challenging constraints of the Solar Orbiter mission it was required
  to further develop existing technologies. As part of this development,
  and of its maturation of technology readiness, a set of breadboard and
  prototypes of critical subsystems have thus been realized to improve
  the overall instrument design. The EUI instrument architecture, its
  major components and sub-systems are described with their driving
  constraints and the expected performances based on the breadboard and
  prototype results. The instrument verification and qualification plan
  will also be discussed. We present the thermal and mechanical model
  validation, the instrument test campaign with the structural-thermal
  model (STM), followed by the other instrument models in advance of
  the flight instrument manufacturing and AIT campaign.

---------------------------------------------------------
Title: Seismic Evidence for a Rapidly Rotating Core in a
    Lower-giant-branch Star Observed with Kepler
Authors: Deheuvels, S.; García, R. A.; Chaplin, W. J.; Basu, S.;
   Antia, H. M.; Appourchaux, T.; Benomar, O.; Davies, G. R.; Elsworth,
   Y.; Gizon, L.; Goupil, M. J.; Reese, D. R.; Regulo, C.; Schou, J.;
   Stahn, T.; Casagrande, L.; Christensen-Dalsgaard, J.; Fischer, D.;
   Hekker, S.; Kjeldsen, H.; Mathur, S.; Mosser, B.; Pinsonneault, M.;
   Valenti, J.; Christiansen, J. L.; Kinemuchi, K.; Mullally, F.
2012ApJ...756...19D    Altcode: 2012arXiv1206.3312D
  Rotation is expected to have an important influence on the structure
  and the evolution of stars. However, the mechanisms of angular momentum
  transport in stars remain theoretically uncertain and very complex to
  take into account in stellar models. To achieve a better understanding
  of these processes, we desperately need observational constraints on the
  internal rotation of stars, which until very recently was restricted to
  the Sun. In this paper, we report the detection of mixed modes—i.e.,
  modes that behave both as g modes in the core and as p modes in
  the envelope—in the spectrum of the early red giant KIC 7341231,
  which was observed during one year with the Kepler spacecraft. By
  performing an analysis of the oscillation spectrum of the star, we
  show that its non-radial modes are clearly split by stellar rotation
  and we are able to determine precisely the rotational splittings of
  18 modes. We then find a stellar model that reproduces very well the
  observed atmospheric and seismic properties of the star. We use this
  model to perform inversions of the internal rotation profile of the
  star, which enables us to show that the core of the star is rotating at
  least five times faster than the envelope. This will shed new light on
  the processes of transport of angular momentum in stars. In particular,
  this result can be used to place constraints on the angular momentum
  coupling between the core and the envelope of early red giants, which
  could help us discriminate between the theories that have been proposed
  over the last few decades.

---------------------------------------------------------
Title: Oscillation mode frequencies of 61 main-sequence and subgiant
    stars observed by Kepler
Authors: Appourchaux, T.; Chaplin, W. J.; García, R. A.; Gruberbauer,
   M.; Verner, G. A.; Antia, H. M.; Benomar, O.; Campante, T. L.; Davies,
   G. R.; Deheuvels, S.; Handberg, R.; Hekker, S.; Howe, R.; Régulo,
   C.; Salabert, D.; Bedding, T. R.; White, T. R.; Ballot, J.; Mathur,
   S.; Silva Aguirre, V.; Elsworth, Y. P.; Basu, S.; Gilliland, R. L.;
   Christensen-Dalsgaard, J.; Kjeldsen, H.; Uddin, K.; Stumpe, M. C.;
   Barclay, T.
2012A&A...543A..54A    Altcode: 2012arXiv1204.3147A
  Context. Solar-like oscillations have been observed by Kepler and CoRoT
  in several solar-type stars, thereby providing a way to probe the stars
  using asteroseismology <BR /> Aims: We provide the mode frequencies of
  the oscillations of various stars required to perform a comparison with
  those obtained from stellar modelling. <BR /> Methods: We used a time
  series of nine months of data for each star. The 61 stars observed were
  categorised in three groups: simple, F-like, and mixed-mode. The simple
  group includes stars for which the identification of the mode degree is
  obvious. The F-like group includes stars for which the identification
  of the degree is ambiguous. The mixed-mode group includes evolved stars
  for which the modes do not follow the asymptotic relation of low-degree
  frequencies. Following this categorisation, the power spectra of the
  61 main-sequence and subgiant stars were analysed using both maximum
  likelihood estimators and Bayesian estimators, providing individual mode
  characteristics such as frequencies, linewidths, and mode heights. We
  developed and describe a methodology for extracting a single set of
  mode frequencies from multiple sets derived by different methods and
  individual scientists. We report on how one can assess the quality of
  the fitted parameters using the likelihood ratio test and the posterior
  probabilities. <BR /> Results: We provide the mode frequencies of
  61 stars (with their 1-σ error bars), as well as their associated
  échelle diagrams. <P />Appendices are available in electronic form
  at <A href="http://www.aanda.org">http://www.aanda.org</A>

---------------------------------------------------------
Title: Accurate fundamental parameters and detailed abundance patterns
    from spectroscopy of 93 solar-type Kepler targets
Authors: Bruntt, H.; Basu, S.; Smalley, B.; Chaplin, W. J.; Verner,
   G. A.; Bedding, T. R.; Catala, C.; Gazzano, J. -C.; Molenda-Żakowicz,
   J.; Thygesen, A. O.; Uytterhoeven, K.; Hekker, S.; Huber, D.; Karoff,
   C.; Mathur, S.; Mosser, B.; Appourchaux, T.; Campante, T. L.; Elsworth,
   Y.; García, R. A.; Handberg, R.; Metcalfe, T. S.; Quirion, P. -O.;
   Régulo, C.; Roxburgh, I. W.; Stello, D.; Christensen-Dalsgaard,
   J.; Kawaler, S. D.; Kjeldsen, H.; Morris, R. L.; Quintana, E. V.;
   Sanderfer, D. T.
2012MNRAS.423..122B    Altcode: 2012arXiv1203.0611B; 2012MNRAS.tmp.3037B
  We present a detailed spectroscopic study of 93 solar-type stars
  that are targets of the NASA/Kepler mission and provide detailed
  chemical composition of each target. We find that the overall
  metallicity is well represented by Fe lines. Relative abundances
  of light elements (CNO) and α elements are generally higher for
  low-metallicity stars. Our spectroscopic analysis benefits from the
  accurately measured surface gravity from the asteroseismic analysis
  of the Kepler light curves. The accuracy on the log g parameter is
  better than 0.03 dex and is held fixed in the analysis. We compare
  our T<SUB>eff</SUB> determination with a recent colour calibration of
  V<SUB>T</SUB>-K<SUB>S</SUB> [TYCHO V magnitude minus Two Micron All Sky
  Survey (2MASS) K<SUB>S</SUB> magnitude] and find very good agreement
  and a scatter of only 80 K, showing that for other nearby Kepler
  targets, this index can be used. The asteroseismic log g values agree
  very well with the classical determination using Fe I-Fe II balance,
  although we find a small systematic offset of 0.08 dex (asteroseismic
  log g values are lower). The abundance patterns of metals, α elements
  and the light elements (CNO) show that a simple scaling by [Fe/H]
  is adequate to represent the metallicity of the stars, except for
  the stars with metallicity below -0.3, where α-enhancement becomes
  important. However, this is only important for a very small fraction of
  the Kepler sample. We therefore recommend that a simple scaling with
  [Fe/H] be employed in the asteroseismic analyses of large ensembles
  of solar-type stars.

---------------------------------------------------------
Title: Solving the Mode Identification Problem in Asteroseismology
    of F Stars Observed with Kepler
Authors: White, Timothy R.; Bedding, Timothy R.; Gruberbauer, Michael;
   Benomar, Othman; Stello, Dennis; Appourchaux, Thierry; Chaplin,
   William J.; Christensen-Dalsgaard, Jørgen; Elsworth, Yvonne P.;
   García, Rafael A.; Hekker, Saskia; Huber, Daniel; Kjeldsen, Hans;
   Mosser, Benoît; Kinemuchi, Karen; Mullally, Fergal; Still, Martin
2012ApJ...751L..36W    Altcode: 2012arXiv1205.0544W
  Asteroseismology of F-type stars has been hindered by an ambiguity in
  identification of their oscillation modes. The regular mode pattern
  that makes this task trivial in cooler stars is masked by increased
  line widths. The absolute mode frequencies, encapsulated in the
  asteroseismic variable epsilon, can help solve this impasse because
  the values of epsilon implied by the two possible mode identifications
  are distinct. We find that the correct epsilon can be deduced from the
  effective temperature and the line widths and we apply these methods
  to a sample of solar-like oscillators observed with Kepler.

---------------------------------------------------------
Title: Damping rates of solar-like oscillations across the HR
    diagram. Theoretical calculations confronted to CoRoT and Kepler
    observations
Authors: Belkacem, K.; Dupret, M. A.; Baudin, F.; Appourchaux, T.;
   Marques, J. P.; Samadi, R.
2012A&A...540L...7B    Altcode: 2012arXiv1203.1737B
  The space-borne missions CoRoT and Kepler are providing a rich harvest
  of high-quality constraints on solar-like pulsators. Among the seismic
  parameters, mode damping rates remains poorly understood and are thus
  barely used to infer the physical properties of stars. Nevertheless,
  thanks to the CoRoT and Kepler spacecrafts it is now possible to measure
  damping rates for hundreds of main-sequence and thousands of red-giant
  stars with unprecedented precision. By using a non-adiabatic pulsation
  code including a time-dependent convection treatment, we compute
  damping rates for stellar models that are representative of solar-like
  pulsators from the main-sequence to the red-giant phase. This allows us
  to reproduce the observations of both CoRoT and Kepler, which validates
  our modeling of mode damping rates and thus the underlying physical
  mechanisms included in the modeling. By considering the perturbations
  of turbulent pressure and entropy (including the perturbation of the
  dissipation rate of turbulent energy into heat) by the oscillation
  in our computation, we succeed in reproducing the observed relation
  between damping rates and effective temperature. Moreover, we discuss
  the physical reasons for mode damping rates to scale with effective
  temperature, as observationally exhibited. Finally, this opens the
  way for the use of mode damping rates to probe turbulent convection
  in solar-like stars.

---------------------------------------------------------
Title: A Uniform Asteroseismic Analysis of 22 Solar-type Stars
    Observed by Kepler
Authors: Mathur, S.; Metcalfe, T. S.; Woitaszek, M.; Bruntt, H.;
   Verner, G. A.; Christensen-Dalsgaard, J.; Creevey, O. L.; Doǧan, G.;
   Basu, S.; Karoff, C.; Stello, D.; Appourchaux, T.; Campante, T. L.;
   Chaplin, W. J.; García, R. A.; Bedding, T. R.; Benomar, O.; Bonanno,
   A.; Deheuvels, S.; Elsworth, Y.; Gaulme, P.; Guzik, J. A.; Handberg,
   R.; Hekker, S.; Herzberg, W.; Monteiro, M. J. P. F. G.; Piau, L.;
   Quirion, P. -O.; Régulo, C.; Roth, M.; Salabert, D.; Serenelli, A.;
   Thompson, M. J.; Trampedach, R.; White, T. R.; Ballot, J.; Brandão,
   I. M.; Molenda-Żakowicz, J.; Kjeldsen, H.; Twicken, J. D.; Uddin,
   K.; Wohler, B.
2012ApJ...749..152M    Altcode: 2012arXiv1202.2844M
  Asteroseismology with the Kepler space telescope is providing not
  only an improved characterization of exoplanets and their host stars,
  but also a new window on stellar structure and evolution for the
  large sample of solar-type stars in the field. We perform a uniform
  analysis of 22 of the brightest asteroseismic targets with the highest
  signal-to-noise ratio observed for 1 month each during the first year
  of the mission, and we quantify the precision and relative accuracy
  of asteroseismic determinations of the stellar radius, mass, and age
  that are possible using various methods. We present the properties
  of each star in the sample derived from an automated analysis of the
  individual oscillation frequencies and other observational constraints
  using the Asteroseismic Modeling Portal (AMP), and we compare them to
  the results of model-grid-based methods that fit the global oscillation
  properties. We find that fitting the individual frequencies typically
  yields asteroseismic radii and masses to ~1% precision, and ages to
  ~2.5% precision (respectively, 2, 5, and 8 times better than fitting
  the global oscillation properties). The absolute level of agreement
  between the results from different approaches is also encouraging,
  with model-grid-based methods yielding slightly smaller estimates of
  the radius and mass and slightly older values for the stellar age
  relative to AMP, which computes a large number of dedicated models
  for each star. The sample of targets for which this type of analysis
  is possible will grow as longer data sets are obtained during the
  remainder of the mission.

---------------------------------------------------------
Title: Asteroseismology of the Solar Analogs 16 Cyg A and B from
    Kepler Observations
Authors: Metcalfe, T. S.; Chaplin, W. J.; Appourchaux, T.; García,
   R. A.; Basu, S.; Brandão, I.; Creevey, O. L.; Deheuvels, S.; Doǧan,
   G.; Eggenberger, P.; Karoff, C.; Miglio, A.; Stello, D.; Yıldız,
   M.; Çelik, Z.; Antia, H. M.; Benomar, O.; Howe, R.; Régulo, C.;
   Salabert, D.; Stahn, T.; Bedding, T. R.; Davies, G. R.; Elsworth, Y.;
   Gizon, L.; Hekker, S.; Mathur, S.; Mosser, B.; Bryson, S. T.; Still,
   M. D.; Christensen-Dalsgaard, J.; Gilliland, R. L.; Kawaler, S. D.;
   Kjeldsen, H.; Ibrahim, K. A.; Klaus, T. C.; Li, J.
2012ApJ...748L..10M    Altcode: 2012arXiv1201.5966M
  The evolved solar-type stars 16 Cyg A and B have long been studied
  as solar analogs, yielding a glimpse into the future of our own
  Sun. The orbital period of the binary system is too long to provide
  meaningful dynamical constraints on the stellar properties, but
  asteroseismology can help because the stars are among the brightest
  in the Kepler field. We present an analysis of three months of nearly
  uninterrupted photometry of 16 Cyg A and B from the Kepler space
  telescope. We extract a total of 46 and 41 oscillation frequencies
  for the two components, respectively, including a clear detection
  of octupole (l = 3) modes in both stars. We derive the properties
  of each star independently using the Asteroseismic Modeling Portal,
  fitting the individual oscillation frequencies and other observational
  constraints simultaneously. We evaluate the systematic uncertainties
  from an ensemble of results generated by a variety of stellar evolution
  codes and fitting methods. The optimal models derived by fitting each
  component individually yield a common age (t = 6.8 ± 0.4 Gyr) and
  initial composition (Z <SUB>i</SUB> = 0.024 ± 0.002, Y <SUB>i</SUB> =
  0.25 ± 0.01) within the uncertainties, as expected for the components
  of a binary system, bolstering our confidence in the reliability of
  asteroseismic techniques. The longer data sets that will ultimately
  become available will allow future studies of differential rotation,
  convection zone depths, and long-term changes due to stellar activity
  cycles.

---------------------------------------------------------
Title: Acoustic spectrum fitting for a large set of solar-like
    pulsators
Authors: Benomar, O.; Baudin, F.; Chaplin, W. J.; Elsworth, Y.;
   Appourchaux, T.
2012MNRAS.420.2178B    Altcode: 2011MNRAS.tmp.2149B
  Asteroseismology provides the means both to constrain the global
  properties and to probe the internal structures of stars. Asteroseismic
  data are now available on large numbers of solar-type stars, thanks
  in particular to the CoRoT and Kepler space missions, and automated
  data-analysis pipelines are needed to provide efficient and timely
  results. Here, we present an automated algorithm that is able to extract
  mode parameters under low signal-to-noise ratio conditions. We use a
  Bayesian framework to ensure the robustness of the algorithm. We discuss
  the efficiency of the method and test it using Variability of Solar
  Irradiance and Gravity Oscillations (VIRGO) Sun-as-a-star photometry
  data and the artificial Astero Fitting at Low Angular degree Group
  (asteroFLAG) Kepler ensemble. Analysis of the VIRGO data shows that
  it is possible to track variations of the individual mode parameters
  (frequency, height, width) through the solar cycle, using short time
  series (30 days). The present analysis also revealed a modulation
  of the degree l = 2 relative height through the solar cycle. Applied
  on asteroFLAG data, we show that the pipeline extracts accurately the
  central frequency and the large separation. It is also able to identify
  the degree of the modes in 78 per cent of stars.

---------------------------------------------------------
Title: Kepler-21b: A 1.6 R <SUB>Earth</SUB> Planet Transiting the
    Bright Oscillating F Subgiant Star HD 179070
Authors: Howell, Steve B.; Rowe, Jason F.; Bryson, Stephen T.; Quinn,
   Samuel N.; Marcy, Geoffrey W.; Isaacson, Howard; Ciardi, David R.;
   Chaplin, William J.; Metcalfe, Travis S.; Monteiro, Mario J. P. F. G.;
   Appourchaux, Thierry; Basu, Sarbani; Creevey, Orlagh L.; Gilliland,
   Ronald L.; Quirion, Pierre-Olivier; Stello, Denis; Kjeldsen, Hans;
   Christensen-Dalsgaard, Jörgen; Elsworth, Yvonne; García, Rafael
   A.; Houdek, Günter; Karoff, Christoffer; Molenda-Żakowicz, Joanna;
   Thompson, Michael J.; Verner, Graham A.; Torres, Guillermo; Fressin,
   Francois; Crepp, Justin R.; Adams, Elisabeth; Dupree, Andrea; Sasselov,
   Dimitar D.; Dressing, Courtney D.; Borucki, William J.; Koch, David
   G.; Lissauer, Jack J.; Latham, David W.; Buchhave, Lars A.; Gautier,
   Thomas N., III; Everett, Mark; Horch, Elliott; Batalha, Natalie M.;
   Dunham, Edward W.; Szkody, Paula; Silva, David R.; Mighell, Ken;
   Holberg, Jay; Ballot, Jerôme; Bedding, Timothy R.; Bruntt, Hans;
   Campante, Tiago L.; Handberg, Rasmus; Hekker, Saskia; Huber, Daniel;
   Mathur, Savita; Mosser, Benoit; Régulo, Clara; White, Timothy R.;
   Christiansen, Jessie L.; Middour, Christopher K.; Haas, Michael R.;
   Hall, Jennifer R.; Jenkins, Jon M.; McCaulif, Sean; Fanelli, Michael
   N.; Kulesa, Craig; McCarthy, Don; Henze, Christopher E.
2012ApJ...746..123H    Altcode: 2011arXiv1112.2165H
  We present Kepler observations of the bright (V = 8.3), oscillating
  star HD 179070. The observations show transit-like events which
  reveal that the star is orbited every 2.8 days by a small, 1.6 R
  <SUB>Earth</SUB> object. Seismic studies of HD 179070 using short
  cadence Kepler observations show that HD 179070 has a frequency-power
  spectrum consistent with solar-like oscillations that are acoustic
  p-modes. Asteroseismic analysis provides robust values for the mass
  and radius of HD 179070, 1.34 ± 0.06 M <SUB>⊙</SUB> and 1.86 ±
  0.04 R <SUB>⊙</SUB>, respectively, as well as yielding an age of
  2.84 ± 0.34 Gyr for this F5 subgiant. Together with ground-based
  follow-up observations, analysis of the Kepler light curves and
  image data, and blend scenario models, we conservatively show at the
  &gt;99.7% confidence level (3σ) that the transit event is caused by
  a 1.64 ± 0.04 R <SUB>Earth</SUB> exoplanet in a 2.785755 ± 0.000032
  day orbit. The exoplanet is only 0.04 AU away from the star and our
  spectroscopic observations provide an upper limit to its mass of ~10 M
  <SUB>Earth</SUB> (2σ). HD 179070 is the brightest exoplanet host star
  yet discovered by Kepler. <P />Based in part on observations obtained
  at the W. M. Keck Observatory, which is operated by the University
  of California and the California Institute of Technology, the Mayall
  telescope at Kitt Peak National Observatory, and the WIYN Observatory
  which is a joint facility of NOAO, University of Wisconsin-Madison,
  Indiana University, and Yale University.

---------------------------------------------------------
Title: Oscillation mode linewidths of main-sequence and subgiant
    stars observed by Kepler
Authors: Appourchaux, T.; Benomar, O.; Gruberbauer, M.; Chaplin,
   W. J.; García, R. A.; Handberg, R.; Verner, G. A.; Antia, H. M.;
   Campante, T. L.; Davies, G. R.; Deheuvels, S.; Hekker, S.; Howe,
   R.; Salabert, D.; Bedding, T. R.; White, T. R.; Houdek, G.; Silva
   Aguirre, V.; Elsworth, Y. P.; van Cleve, J.; Clarke, B. D.; Hall,
   J. R.; Kjeldsen, H.
2012A&A...537A.134A    Altcode: 2011arXiv1112.3295A
  Context. Solar-like oscillations have been observed by Kepler and CoRoT
  in several solar-type stars. <BR /> Aims: We study the variations in the
  stellar p-mode linewidth as a function of effective temperature. <BR
  /> Methods: We study a time series of nine months of Kepler data. We
  analyse the power spectra of 42 cool main-sequence stars and subgiants
  using both maximum likelihood estimators and Bayesian estimators
  to recover individual mode characteristics such as frequencies,
  linewidths, and mode heights. <BR /> Results: We report on the mode
  linewidth at both maximum power and maximum mode height for these 42
  stars as a function of effective temperature. <BR /> Conclusions: We
  show that the mode linewidth at either maximum mode height or maximum
  amplitude follows a scaling relation with effective temperature,
  which is a combination of a power law and a lower bound. The typical
  power-law index is about 13 for the linewidth derived from the maximum
  mode height, and about 16 for the linewidth derived from the maximum
  amplitude, while the lower bound is about 0.3 μHz and 0.7 μHz,
  respectively. We stress that this scaling relation is only valid for
  cool main-sequence stars and subgiants, and does not have any predictive
  power outside the temperature range of these stars.

---------------------------------------------------------
Title: Testing Scaling Relations for Solar-like Oscillations from
    the Main Sequence to Red Giants Using Kepler Data
Authors: Huber, D.; Bedding, T. R.; Stello, D.; Hekker, S.; Mathur,
   S.; Mosser, B.; Verner, G. A.; Bonanno, A.; Buzasi, D. L.; Campante,
   T. L.; Elsworth, Y. P.; Hale, S. J.; Kallinger, T.; Silva Aguirre,
   V.; Chaplin, W. J.; De Ridder, J.; García, R. A.; Appourchaux,
   T.; Frandsen, S.; Houdek, G.; Molenda-Żakowicz, J.; Monteiro,
   M. J. P. F. G.; Christensen-Dalsgaard, J.; Gilliland, R. L.; Kawaler,
   S. D.; Kjeldsen, H.; Broomhall, A. M.; Corsaro, E.; Salabert, D.;
   Sanderfer, D. T.; Seader, S. E.; Smith, J. C.
2011ApJ...743..143H    Altcode: 2011arXiv1109.3460H
  We have analyzed solar-like oscillations in ~1700 stars observed by the
  Kepler Mission, spanning from the main sequence to the red clump. Using
  evolutionary models, we test asteroseismic scaling relations for the
  frequency of maximum power (ν<SUB>max</SUB>), the large frequency
  separation (Δν), and oscillation amplitudes. We show that the
  difference of the Δν-ν<SUB>max</SUB> relation for unevolved and
  evolved stars can be explained by different distributions in effective
  temperature and stellar mass, in agreement with what is expected from
  scaling relations. For oscillation amplitudes, we show that neither
  (L/M)<SUP> s </SUP> scaling nor the revised scaling relation by Kjeldsen
  &amp; Bedding is accurate for red-giant stars, and demonstrate that a
  revised scaling relation with a separate luminosity-mass dependence can
  be used to calculate amplitudes from the main sequence to red giants
  to a precision of ~25%. The residuals show an offset particularly for
  unevolved stars, suggesting that an additional physical dependency is
  necessary to fully reproduce the observed amplitudes. We investigate
  correlations between amplitudes and stellar activity, and find evidence
  that the effect of amplitude suppression is most pronounced for subgiant
  stars. Finally, we test the location of the cool edge of the instability
  strip in the Hertzsprung-Russell diagram using solar-like oscillations
  and find the detections in the hottest stars compatible with a domain
  of hybrid stochastically excited and opacity driven pulsation.

---------------------------------------------------------
Title: Asteroseismic Diagrams from a Survey of Solar-like Oscillations
    with Kepler
Authors: White, Timothy R.; Bedding, Timothy R.; Stello, Dennis;
   Appourchaux, Thierry; Ballot, Jérôme; Benomar, Othman; Bonanno,
   Alfio; Broomhall, Anne-Marie; Campante, Tiago L.; Chaplin, William
   J.; Christensen-Dalsgaard, Jørgen; Corsaro, Enrico; Doǧan, Gülnur;
   Elsworth, Yvonne P.; Fletcher, Stephen T.; García, Rafael A.; Gaulme,
   Patrick; Handberg, Rasmus; Hekker, Saskia; Huber, Daniel; Karoff,
   Christoffer; Kjeldsen, Hans; Mathur, Savita; Mosser, Benoit; Monteiro,
   Mario J. P. F. G.; Régulo, Clara; Salabert, David; Silva Aguirre,
   Victor; Thompson, Michael J.; Verner, Graham; Morris, Robert L.;
   Sanderfer, Dwight T.; Seader, Shawn E.
2011ApJ...742L...3W    Altcode: 2011arXiv1110.1375W
  Photometric observations made by the NASA Kepler Mission have led to a
  dramatic increase in the number of main-sequence and subgiant stars with
  detected solar-like oscillations. We present an ensemble asteroseismic
  analysis of 76 solar-type stars. Using frequencies determined from the
  Kepler time-series photometry, we have measured three asteroseismic
  parameters that characterize the oscillations: the large frequency
  separation (Δν), the small frequency separation between modes of
  l = 0 and l = 2 (δν<SUB>02</SUB>), and the dimensionless offset
  (epsilon). These measurements allow us to construct asteroseismic
  diagrams, namely the so-called Christensen-Dalsgaard diagram of
  δν<SUB>02</SUB> versus Δν, and the recently re-introduced epsilon
  diagram. We compare the Kepler results with previously observed
  solar-type stars and with theoretical models. The positions of
  stars in these diagrams places constraints on their masses and
  ages. Additionally, we confirm the observational relationship
  between epsilon and T <SUB>eff</SUB> that allows for the unambiguous
  determination of radial order and should help resolve the problem of
  mode identification in F stars.

---------------------------------------------------------
Title: Constructing a One-solar-mass Evolutionary Sequence Using
    Asteroseismic Data from Kepler
Authors: Silva Aguirre, V.; Chaplin, W. J.; Ballot, J.; Basu,
   S.; Bedding, T. R.; Serenelli, A. M.; Verner, G. A.; Miglio, A.;
   Monteiro, M. J. P. F. G.; Weiss, A.; Appourchaux, T.; Bonanno,
   A.; Broomhall, A. M.; Bruntt, H.; Campante, T. L.; Casagrande, L.;
   Corsaro, E.; Elsworth, Y.; García, R. A.; Gaulme, P.; Handberg,
   R.; Hekker, S.; Huber, D.; Karoff, C.; Mathur, S.; Mosser, B.;
   Salabert, D.; Schönrich, R.; Sousa, S. G.; Stello, D.; White, T. R.;
   Christensen-Dalsgaard, J.; Gilliland, R. L.; Kawaler, S. D.; Kjeldsen,
   H.; Houdek, G.; Metcalfe, T. S.; Molenda-Żakowicz, J.; Thompson,
   M. J.; Caldwell, D. A.; Christiansen, J. L.; Wohler, B.
2011ApJ...740L...2S    Altcode: 2011arXiv1108.2031S
  Asteroseismology of solar-type stars has entered a new era of
  large surveys with the success of the NASA Kepler mission, which
  is providing exquisite data on oscillations of stars across the
  Hertzsprung-Russell diagram. From the time-series photometry, the two
  seismic parameters that can be most readily extracted are the large
  frequency separation (Δν) and the frequency of maximum oscillation
  power (ν<SUB>max</SUB>). After the survey phase, these quantities
  are available for hundreds of solar-type stars. By scaling from solar
  values, we use these two asteroseismic observables to identify for the
  first time an evolutionary sequence of 1 M <SUB>sun</SUB> field stars,
  without the need for further information from stellar models. Comparison
  of our determinations with the few available spectroscopic results
  shows an excellent level of agreement. We discuss the potential of the
  method for differential analysis throughout the main-sequence evolution
  and the possibility of detecting twins of very well-known stars.

---------------------------------------------------------
Title: Asteroseismology from multi-month Kepler photometry: the
    evolved Sun-like stars KIC 10273246 and KIC 10920273
Authors: Campante, T. L.; Handberg, R.; Mathur, S.; Appourchaux, T.;
   Bedding, T. R.; Chaplin, W. J.; García, R. A.; Mosser, B.; Benomar,
   O.; Bonanno, A.; Corsaro, E.; Fletcher, S. T.; Gaulme, P.; Hekker, S.;
   Karoff, C.; Régulo, C.; Salabert, D.; Verner, G. A.; White, T. R.;
   Houdek, G.; Brandão, I. M.; Creevey, O. L.; Doǧan, G.; Bazot,
   M.; Christensen-Dalsgaard, J.; Cunha, M. S.; Elsworth, Y.; Huber,
   D.; Kjeldsen, H.; Lundkvist, M.; Molenda-Żakowicz, J.; Monteiro,
   M. J. P. F. G.; Stello, D.; Clarke, B. D.; Girouard, F. R.; Hall, J. R.
2011A&A...534A...6C    Altcode: 2011arXiv1108.3807C
  Context. The evolved main-sequence Sun-like stars KIC 10273246 (F-type)
  and KIC 10920273 (G-type) were observed with the NASA Kepler satellite
  for approximately ten months with a duty cycle in excess of 90%. Such
  continuous and long observations are unprecedented for solar-type
  stars other than the Sun. <BR /> Aims: We aimed mainly at extracting
  estimates of p-mode frequencies - as well as of other individual mode
  parameters - from the power spectra of the light curves of both stars,
  thus providing scope for a full seismic characterization. <BR />
  Methods: The light curves were corrected for instrumental effects in
  a manner independent of the Kepler science pipeline. Estimation of
  individual mode parameters was based both on the maximization of the
  likelihood of a model describing the power spectrum and on a classic
  prewhitening method. Finally, we employed a procedure for selecting
  frequency lists to be used in stellar modeling. <BR /> Results: A
  total of 30 and 21 modes of degree l = 0,1,2 - spanning at least eight
  radial orders - have been identified for KIC 10273246 and KIC 10920273,
  respectively. Two avoided crossings (l = 1 ridge) have been identified
  for KIC 10273246, whereas one avoided crossing plus another likely
  one have been identified for KIC 10920273. Good agreement is found
  between observed and predicted mode amplitudes for the F-type star KIC
  10273246, based on a revised scaling relation. Estimates are given of
  the rotational periods, the parameters describing stellar granulation
  and the global asteroseismic parameters Δν and ν<SUB>max</SUB>.

---------------------------------------------------------
Title: Verification of the Kepler Input Catalog from Asteroseismology
    of Solar-type Stars
Authors: Verner, G. A.; Chaplin, W. J.; Basu, S.; Brown, T. M.;
   Hekker, S.; Huber, D.; Karoff, C.; Mathur, S.; Metcalfe, T. S.;
   Mosser, B.; Quirion, P. -O.; Appourchaux, T.; Bedding, T. R.; Bruntt,
   H.; Campante, T. L.; Elsworth, Y.; García, R. A.; Handberg, R.;
   Régulo, C.; Roxburgh, I. W.; Stello, D.; Christensen-Dalsgaard, J.;
   Gilliland, R. L.; Kawaler, S. D.; Kjeldsen, H.; Allen, C.; Clarke,
   B. D.; Girouard, F. R.
2011ApJ...738L..28V    Altcode: 2011arXiv1109.0869V
  We calculate precise stellar radii and surface gravities from the
  asteroseismic analysis of over 500 solar-type pulsating stars observed
  by the Kepler space telescope. These physical stellar properties
  are compared with those given in the Kepler Input Catalog (KIC),
  determined from ground-based multi-color photometry. For the stars
  in our sample, we find general agreement but we detect an average
  overestimation bias of 0.23 dex in the KIC determination of log (g)
  for stars with log (g)<SUB>KIC</SUB> &gt; 4.0 dex, and a resultant
  underestimation bias of up to 50% in the KIC radii estimates for stars
  with R <SUB>KIC</SUB> &lt; 2 R <SUB>sun</SUB>. Part of the difference
  may arise from selection bias in the asteroseismic sample; nevertheless,
  this result implies there may be fewer stars characterized in the KIC
  with R ~ 1 R <SUB>sun</SUB> than is suggested by the physical properties
  in the KIC. Furthermore, if the radius estimates are taken from the
  KIC for these affected stars and then used to calculate the size of
  transiting planets, a similar underestimation bias may be applied to
  the planetary radii.

---------------------------------------------------------
Title: Global asteroseismic properties of solar-like oscillations
observed by Kepler: a comparison of complementary analysis methods
Authors: Verner, G. A.; Elsworth, Y.; Chaplin, W. J.; Campante,
   T. L.; Corsaro, E.; Gaulme, P.; Hekker, S.; Huber, D.; Karoff, C.;
   Mathur, S.; Mosser, B.; Appourchaux, T.; Ballot, J.; Bedding, T. R.;
   Bonanno, A.; Broomhall, A. -M.; García, R. A.; Handberg, R.; New,
   R.; Stello, D.; Régulo, C.; Roxburgh, I. W.; Salabert, D.; White,
   T. R.; Caldwell, D. A.; Christiansen, J. L.; Fanelli, M. N.
2011MNRAS.415.3539V    Altcode: 2011MNRAS.tmp..892V; 2011arXiv1105.0571V
  We present the asteroseismic analysis of 1948 F-, G- and K-type
  main-sequence and subgiant stars observed by the National Aeronautics
  and Space Administration Kepler mission. We detect and characterize
  solar-like oscillations in 642 of these stars. This represents the
  largest cohort of main-sequence and subgiant solar-like oscillators
  observed to date. The photometric observations are analysed using the
  methods developed by nine independent research teams. The results are
  combined to validate the determined global asteroseismic parameters
  and calculate the relative precision by which the parameters can be
  obtained. We correlate the relative number of detected solar-like
  oscillators with stellar parameters from the Kepler Input Catalogue
  and find a deficiency for stars with effective temperatures in the
  range 5300 ≲T<SUB>eff</SUB>≲ 5700 K and a drop-off in detected
  oscillations in stars approaching the red edge of the classical
  instability strip. We compare the power-law relationships between the
  frequency of peak power, ν<SUB>max</SUB>, the mean large frequency
  separation, Δν, and the maximum mode amplitude, A<SUB>max</SUB>,
  and show that there are significant method-dependent differences in the
  results obtained. This illustrates the need for multiple complementary
  analysis methods to be used to assess the robustness and reproducibility
  of results derived from global asteroseismic parameters.

---------------------------------------------------------
Title: Solar-like Oscillations in KIC 11395018 and KIC 11234888 from
    8 Months of Kepler Data
Authors: Mathur, S.; Handberg, R.; Campante, T. L.; García, R. A.;
   Appourchaux, T.; Bedding, T. R.; Mosser, B.; Chaplin, W. J.; Ballot,
   J.; Benomar, O.; Bonanno, A.; Corsaro, E.; Gaulme, P.; Hekker,
   S.; Régulo, C.; Salabert, D.; Verner, G.; White, T. R.; Brandão,
   I. M.; Creevey, O. L.; Doǧan, G.; Elsworth, Y.; Huber, D.; Hale,
   S. J.; Houdek, G.; Karoff, C.; Metcalfe, T. S.; Molenda-Żakowicz,
   J.; Monteiro, M. J. P. F. G.; Thompson, M. J.; Christensen-Dalsgaard,
   J.; Gilliland, R. L.; Kawaler, S. D.; Kjeldsen, H.; Quintana, E. V.;
   Sanderfer, D. T.; Seader, S. E.
2011ApJ...733...95M    Altcode: 2011arXiv1103.4085M
  We analyze the photometric short-cadence data obtained with the Kepler
  mission during the first 8 months of observations of two solar-type
  stars of spectral types G and F: KIC 11395018 and KIC 11234888,
  respectively, the latter having a lower signal-to-noise ratio (S/N)
  compared with the former. We estimate global parameters of the acoustic
  (p) modes such as the average large and small frequency separations, the
  frequency of the maximum of the p-mode envelope, and the average line
  width of the acoustic modes. We were able to identify and to measure
  22 p-mode frequencies for the first star and 16 for the second one
  even though the S/N of these stars are rather low. We also derive some
  information about the stellar rotation periods from the analyses of the
  low-frequency parts of the power spectral densities. A model-independent
  estimation of the mean density, mass, and radius is obtained using the
  scaling laws. We emphasize the importance of continued observations
  for the stars with low S/N for an improved characterization of the
  oscillation modes. Our results offer a preview of what will be possible
  for many stars with the long data sets obtained during the remainder
  of the mission.

---------------------------------------------------------
Title: Preparation of Kepler light curves for asteroseismic analyses
Authors: García, R. A.; Hekker, S.; Stello, D.; Gutiérrez-Soto,
   J.; Handberg, R.; Huber, D.; Karoff, C.; Uytterhoeven, K.;
   Appourchaux, T.; Chaplin, W. J.; Elsworth, Y.; Mathur, S.; Ballot,
   J.; Christensen-Dalsgaard, J.; Gilliland, R. L.; Houdek, G.; Jenkins,
   J. M.; Kjeldsen, H.; McCauliff, S.; Metcalfe, T.; Middour, C. K.;
   Molenda-Zakowicz, J.; Monteiro, M. J. P. F. G.; Smith, J. C.; Thompson,
   M. J.
2011MNRAS.414L...6G    Altcode: 2011arXiv1103.0382G
  The Kepler mission is providing photometric data of exquisite
  quality for the asteroseismic study of different classes of pulsating
  stars. These analyses place particular demands on the pre-processing
  of the data, over a range of time-scales from minutes to months. Here,
  we describe processing procedures developed by the Kepler Asteroseismic
  Science Consortium to prepare light curves that are optimized for the
  asteroseismic study of solar-like oscillating stars in which outliers,
  jumps and drifts are corrected.

---------------------------------------------------------
Title: Accurate p-mode measurements of the G0V metal-rich CoRoT
    target HD 52265
Authors: Ballot, J.; Gizon, L.; Samadi, R.; Vauclair, G.; Benomar, O.;
   Bruntt, H.; Mosser, B.; Stahn, T.; Verner, G. A.; Campante, T. L.;
   García, R. A.; Mathur, S.; Salabert, D.; Gaulme, P.; Régulo, C.;
   Roxburgh, I. W.; Appourchaux, T.; Baudin, F.; Catala, C.; Chaplin,
   W. J.; Deheuvels, S.; Michel, E.; Bazot, M.; Creevey, O.; Dolez, N.;
   Elsworth, Y.; Sato, K. H.; Vauclair, S.; Auvergne, M.; Baglin, A.
2011A&A...530A..97B    Altcode: 2011arXiv1105.3551B
  Context. The star <ASTROBJ>HD 52265</ASTROBJ> is a G0V metal-rich
  exoplanet-host star observed in the seismology field of the CoRoT
  space telescope from November 2008 to March 2009. The satellite
  collected 117 days of high-precision photometric data on this star,
  showing that it presents solar-like oscillations. HD 52265 was also
  observed in spectroscopy with the Narval spectrograph at the same
  epoch. <BR /> Aims: We characterise HD 52265 using both spectroscopic
  and seismic data. <BR /> Methods: The fundamental stellar parameters
  of HD 52265 were derived with the semi-automatic software VWA, and
  the projected rotational velocity was estimated by fitting synthetic
  profiles to isolated lines in the observed spectrum. The parameters
  of the observed p modes were determined with a maximum-likelihood
  estimation. We performed a global fit of the oscillation spectrum,
  over about ten radial orders, for degrees l = 0 to 2. We also derived
  the properties of the granulation, and analysed a signature of the
  rotation induced by the photospheric magnetic activity. <BR /> Results:
  Precise determinations of fundamental parameters have been obtained:
  T<SUB>eff</SUB> = 6100 ± 60 K, log g = 4.35 ± 0.09, [M/H] = 0.19 ±
  0.05, as well as vsini=3.6<SUP>+0.3</SUP><SUB>-1.0kms</SUB>. We have
  measured a mean rotation period P<SUB>rot</SUB> = 12.3 ± 0.15 days,
  and find a signature of differential rotation. The frequencies of 31
  modes are reported in the range 1500-2550 μHz. The large separation
  exhibits a clear modulation around the mean value Dnu=98.3 ± 0.1
  μHz. Mode widths vary with frequency along an S-shape with a clear
  local maximum around 1800 μHz. We deduce lifetimes ranging between
  0.5 and 3 days for these modes. Finally, we find a maximal bolometric
  amplitude of about 3.96 ± 0.24 ppm for radial modes. <P />The CoRoT
  space mission, launched on December 27th 2006, has been developed
  and is operated by CNES, with the contribution of Austria, Belgium,
  Brazil, ESA (RSSD and Science Programme), Germany and Spain.

---------------------------------------------------------
Title: Predicting the Detectability of Oscillations in Solar-type
    Stars Observed by Kepler
Authors: Chaplin, W. J.; Kjeldsen, H.; Bedding, T. R.;
   Christensen-Dalsgaard, J.; Gilliland, R. L.; Kawaler, S. D.;
   Appourchaux, T.; Elsworth, Y.; García, R. A.; Houdek, G.; Karoff, C.;
   Metcalfe, T. S.; Molenda-Żakowicz, J.; Monteiro, M. J. P. F. G.;
   Thompson, M. J.; Verner, G. A.; Batalha, N.; Borucki, W. J.;
   Brown, T. M.; Bryson, S. T.; Christiansen, J. L.; Clarke, B. D.;
   Jenkins, J. M.; Klaus, T. C.; Koch, D.; An, D.; Ballot, J.; Basu,
   S.; Benomar, O.; Bonanno, A.; Broomhall, A. -M.; Campante, T. L.;
   Corsaro, E.; Creevey, O. L.; Esch, L.; Gai, N.; Gaulme, P.; Hale,
   S. J.; Handberg, R.; Hekker, S.; Huber, D.; Mathur, S.; Mosser, B.;
   New, R.; Pinsonneault, M. H.; Pricopi, D.; Quirion, P. -O.; Régulo,
   C.; Roxburgh, I. W.; Salabert, D.; Stello, D.; Suran, M. D.
2011ApJ...732...54C    Altcode: 2011arXiv1103.0702C
  Asteroseismology of solar-type stars has an important part to play
  in the exoplanet program of the NASA Kepler Mission. Precise and
  accurate inferences on the stellar properties that are made possible
  by the seismic data allow very tight constraints to be placed on the
  exoplanetary systems. Here, we outline how to make an estimate of the
  detectability of solar-like oscillations in any given Kepler target,
  using rough estimates of the temperature and radius, and the Kepler
  apparent magnitude.

---------------------------------------------------------
Title: Evidence for the Impact of Stellar Activity on the
    Detectability of Solar-like Oscillations Observed by Kepler
Authors: Chaplin, W. J.; Bedding, T. R.; Bonanno, A.; Broomhall,
   A. -M.; García, R. A.; Hekker, S.; Huber, D.; Verner, G. A.;
   Basu, S.; Elsworth, Y.; Houdek, G.; Mathur, S.; Mosser, B.; New,
   R.; Stevens, I. R.; Appourchaux, T.; Karoff, C.; Metcalfe, T. S.;
   Molenda-Żakowicz, J.; Monteiro, M. J. P. F. G.; Thompson, M. J.;
   Christensen-Dalsgaard, J.; Gilliland, R. L.; Kawaler, S. D.; Kjeldsen,
   H.; Ballot, J.; Benomar, O.; Corsaro, E.; Campante, T. L.; Gaulme,
   P.; Hale, S. J.; Handberg, R.; Jarvis, E.; Régulo, C.; Roxburgh,
   I. W.; Salabert, D.; Stello, D.; Mullally, F.; Li, J.; Wohler, W.
2011ApJ...732L...5C    Altcode: 2011arXiv1103.5570C
  We use photometric observations of solar-type stars, made by the NASA
  Kepler Mission, to conduct a statistical study of the impact of stellar
  surface activity on the detectability of solar-like oscillations. We
  find that the number of stars with detected oscillations falls
  significantly with increasing levels of activity. The results present
  strong evidence for the impact of magnetic activity on the properties
  of near-surface convection in the stars, which appears to inhibit
  the amplitudes of the stochastically excited, intrinsically damped
  solar-like oscillations.

---------------------------------------------------------
Title: Ensemble Asteroseismology of Solar-Type Stars with the NASA
    Kepler Mission
Authors: Chaplin, W. J.; Kjeldsen, H.; Christensen-Dalsgaard, J.;
   Basu, S.; Miglio, A.; Appourchaux, T.; Bedding, T. R.; Elsworth, Y.;
   García, R. A.; Gilliland, R. L.; Girardi, L.; Houdek, G.; Karoff,
   C.; Kawaler, S. D.; Metcalfe, T. S.; Molenda-Żakowicz, J.; Monteiro,
   M. J. P. F. G.; Thompson, M. J.; Verner, G. A.; Ballot, J.; Bonanno,
   A.; Brandão, I. M.; Broomhall, A. -M.; Bruntt, H.; Campante, T. L.;
   Corsaro, E.; Creevey, O. L.; Doğan, G.; Esch, L.; Gai, N.; Gaulme,
   P.; Hale, S. J.; Handberg, R.; Hekker, S.; Huber, D.; Jiménez, A.;
   Mathur, S.; Mazumdar, A.; Mosser, B.; New, R.; Pinsonneault, M. H.;
   Pricopi, D.; Quirion, P. -O.; Régulo, C.; Salabert, D.; Serenelli,
   A. M.; Silva Aguirre, V.; Sousa, S. G.; Stello, D.; Stevens, I. R.;
   Suran, M. D.; Uytterhoeven, K.; White, T. R.; Borucki, W. J.; Brown,
   T. M.; Jenkins, J. M.; Kinemuchi, K.; Van Cleve, J.; Klaus, T. C.
2011Sci...332..213C    Altcode: 2011arXiv1109.4723C
  In addition to its search for extrasolar planets, the NASA Kepler
  mission provides exquisite data on stellar oscillations. We report the
  detections of oscillations in 500 solar-type stars in the Kepler field
  of view, an ensemble that is large enough to allow statistical studies
  of intrinsic stellar properties (such as mass, radius, and age) and
  to test theories of stellar evolution. We find that the distribution
  of observed masses of these stars shows intriguing differences to
  predictions from models of synthetic stellar populations in the Galaxy.

---------------------------------------------------------
Title: The Solar Orbiter Mission and its Polarimetric and Helioseismic
    Imager (SO/PHI)
Authors: Gandorfer, Achim; Solanki, Sami K.; Woch, Joachim; Martínez
   Pillet, Valentin; Álvarez Herrero, Alberto; Appourchaux, Thierry
2011JPhCS.271a2086G    Altcode:
  We briefly outline the scientific and instrumental aspects of ESA's
  Solar Orbiter mission. Special emphasis is given to the Polarimetric
  and Helioseismic Imager, the instrument with the highest relevance for
  helioseismology applications, which will observe gas motions and the
  vector magnetic field in the photosphere at high spatial and temporal
  resolution.

---------------------------------------------------------
Title: PLATO : PLAnetary Transits and Oscillations of stars
Authors: Catala, Claude; Appourchaux, Thierry; Plato Mission Consortium
2011JPhCS.271a2084C    Altcode:
  PLATO is a M-class candidate in the ESA Cosmic Vision program. PLATO's
  objective is to characterize exoplanets and their host stars in
  the solar neighbourhood. While it builds on the heritage from CoRoT
  and Kepler, the major breakthrough will come from its strong focus
  on bright targets (m<SUB>V</SUB> &lt;= 11). The PLATO targets will
  also include a large number of very bright (m<SUB>V</SUB> &lt;= 8)
  and nearby stars. <P />The prime science goals of PLATO are: (i) the
  detection and characterization of exoplanetary systems of all kinds,
  including both the planets and their host stars, reaching down to small,
  terrestrial planets in the habitable zone; (ii) the identification
  of suitable targets for future, more detailed characterization,
  including a spectroscopic search for bio-markers in nearby habitable
  exoplanets. <P />These ambitious goals will be reached by ultra-high
  precision, long (few years), uninterrupted photometric monitoring in
  the visible of very large samples of bright stars, which can only be
  done from space. The resulting high quality light curves will be used
  on the one hand to detect planetary transits, as well as to measure
  their characteristics, and on the other hand to provide a seismic
  analysis of the host stars of the detected planets, from which precise
  measurements of their radii, masses, and ages will be derived. <P
  />The PLATO space-based data will be complemented by ground-based
  follow-up observations, in particular very precise radial velocity
  monitoring, which will be used to confirm the planetary nature of the
  detected events and to measure the planet masses. <P />The full set of
  parameters of exoplanetary systems will thus be measured, including
  all characteristics of the host stars and the orbits, radii, masses,
  and ages of the planets, allowing us to derive planet mean densities,
  and estimate their temperature and radiation environment. Finally,
  the knowledge of the age of the exoplanetary systems will allow us to
  put them in an evolutionary perspective.

---------------------------------------------------------
Title: FOREWORD Foreword
Authors: Appourchaux, Thierry
2011JPhCS.271a1001A    Altcode:
  Volume 271 (2011) of the Journal of Physics: Conference Series provides
  a record of the invited and contributed talks, and of the posters
  presented at the GONG2010-SoHO24 conference entitled 'A new era of
  seismology of the Sun and solar-like stars'. The conference was held
  from 27 June 2010 to 2 July 2010 in Aix-en-Provence, France. More than
  120 scientists from all over the world attended the conference. <P
  />I would like to express my gratitude for the the financial support
  from the following organisations: Université Paris-Sud; the Centre
  National d'Etudes Spatiales (CNES); the Programme National des Relations
  Soleil-Terre (PNST) and the Programme National de Physique Stellaire
  (PNPS) (both programmes under the umbrella of the Institut National
  des Sciences de l'Univers, INSU); INSU of the Centre National de la
  Recherche Scientifique (CNRS); the SoHO project of the European Space
  Agency (ESA), and the Science Programme of ESA; the Global Oscillations
  Network Group (GONG); and finally the European Aeronautic Defence
  and Space Company (EADS). <P />The Scientific Organizing Committee
  comprised Thierry Appourchaux (chairman, Institut d'Astrophysique
  Spatiale, Orsay, France), Frank Hill (co-chairman, GONG / National
  Solar Observatory, Tucson, Arizona, United States), Annie Baglin
  (Observatoire de Paris-Meudon, France), William Chaplin (University
  of Birmingham, United Kingdom), Jørgen Christensen-Dalsgaard (Aarhus
  Universitet, Denmark), Thierry Corbard (Observatoire de la Côte d'Azur,
  Nice, France), Bernhard Fleck (European Space Agency), Laurent Gizon
  (Max-Planck-Institut für Sonnensystemforschung, Lindau, Germany),
  Travis Metcalfe (National Center for Atmospheric Research, Boulder,
  Colorado, United States), Michael Thompson (Sheffied University, United
  Kingdom; High Altitude Observatory, Boulder, Colorado, United States)
  and Jesper Schou (Stanford University, California, United States). <P
  />The Editorial Committee of these proceedings was composed of
  Thierry Appourchaux (chairman), Annie Baglin, William Chaplin, Jørgen
  Christensen-Dalsgaard, Laurent Gizon, Michael Thompson, Takashi Sekii
  (National Astronomical Observatory of Japan, Tokyo) and John Leibacher
  (IAS, Orsay, France; GONG / NSO, Tucson, Arizona, United States). <P
  />This volume consists of 86 articles organised in sections reflecting
  the scientific programme of the conference: <P />012001-012024 Local
  helioseismology 012025-012030 Solar diameter, irradiance and activity
  012031-012044 Solar and stellar modelling 012045-012056 Low degree
  stellar seismology 012057-012063 First results from space missions
  012064-012082 Convection, dynamo and flows 012083-012086 Prospective
  <P />All papers are freely accessible on the internet, in colour, at <A
  href="http://iopscience.iop.org/1742-6596/271/1">http://iopscience.iop.org/1742-6596/271/1</A>,
  and an interactive picture of the conference is available in the
  attached PDF. <P />I am also grateful to the Local Organizing
  Committee for making this conference a success: Catherine Cougrand
  (secretary), Stéphane Caminade (web designer), Delphine Prival
  (administration) and Jean-Paul Rozet (logistics). I could
  not have done it without your help! <P />Last but not least,
  let me also thank the official photographer of the conference,
  Pierre Assus, for producing excellent photographs, including
  the group photo. Please feel free to send me an e-mail at <A
  href="Thierry.Appourchaux@ias.u-psud.fr">Thierry.Appourchaux@ias.u-psud.fr</A>
  if you would like copies of these pictures. <P />Thierry Appourchaux
  Editor <P />Orsay, France 24 December 2010 <P />Conference photograph
  <P />IAS logo  Université Paris-Sud logo  CNRS logo  SOHO logo
  <P />ESA logo  NASA logo  Gong logo  EADS ASTRIUM logo

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Title: HD 46375: seismic and spectropolarimetric analysis of a young
    Sun hosting a Saturn-like planet
Authors: Gaulme, P.; Deheuvels, S.; Weiss, W. W.; Mosser, B.; Moutou,
   C.; Bruntt, H.; Donati, J. -F.; Vannier, M.; Guillot, T.; Appourchaux,
   T.; Michel, E.; Auvergne, M.; Samadi, R.; Baudin, F.; Catala, C.;
   Baglin, A.
2010A&A...524A..47G    Altcode: 2010arXiv1011.2671G
  Context. HD 46375 is known to host a Saturn-like exoplanet orbiting at
  0.04 AU from its host star. Stellar light reflected by the planet
  was tentatively identified in the 34-day CoRoT run acquired in
  October-November 2008. <BR /> Aims: We constrain the properties of the
  magnetic field of HD 46375 based on spectropolarimetric observations
  with the NARVAL spectrograph at the Pic du Midi observatory. In
  addition, we use a high-resolution NARVAL flux spectrum to contrain
  the atmospheric parameters. With these constraints, we perform
  an asteroseismic analysis and modelling of HD 46375 using the
  frequencies extracted from the CoRoT light curve. <BR /> Methods:
  We used Zeeman Doppler imaging to reconstruct the magnetic map of the
  stellar surface. In the spectroscopic analysis we fitted isolated lines
  using 1D LTE atmosphere models. This analysis was used to constrain
  the effective temperature, surface gravity, and chemical composition
  of the star. To extract information about the p-mode oscillations,
  we used a technique based on the envelope autocorrelation function
  (EACF). <BR /> Results: From the Zeeman Doppler imaging observations,
  we observe a magnetic field of ≈ 5 Gauss. From the spectral analysis,
  HD 46375 is inferred to be an unevolved K0 type star with high
  metallicity [Fe/H] = +0.39. Owing to the relative faintness of the
  star (m<SUB>hip</SUB> = 8.05), the signal-to-noise ratio is too low
  to identify individual modes. However, we measure the p-mode excess
  power and large separation Δν<SUB>0</SUB> = 153.0±0.7 μHz. <BR />
  Conclusions: We are able do constrain the fundamental parameters of the
  star thanks to spectrometric and seismic analyses. We conclude that
  HD 46375 is similar to a young version of α Cen B. This work is of
  special interest because of its combination of exoplanetary science
  and asteroseismology, which are the subjects of the current Kepler
  mission and the proposed Plato mission. <P />The CoRoT space mission,
  launched on 2006 December 27, was developed and is operated by the
  CNES, with participation of the Science Programs of ESA, ESA's RSSD,
  Austria, Belgium, Brazil, Germany and Spain.

---------------------------------------------------------
Title: Asteroseismology of solar-type stars with Kepler I: Data
    analysis
Authors: Karoff, C.; Chaplin, W. J.; Appourchaux, T.; Elsworth, Y.;
   Garcia, R. A.; Houdek, G.; Metcalfe, T. S.; Molenda-Żakowicz, J.;
   Monteiro, M. J. P. F. G.; Thompson, M. J.; Christensen-Dalsgaard, J.;
   Gilliland, R. L.; Kjeldsen, H.; Basu, S.; Bedding, T. R.; Campante,
   T. L.; Eggenberger, P.; Fletcher, S. T.; Gaulme, P.; Handberg, R.;
   Hekker, S.; Martic, M.; Mathur, S.; Mosser, B.; Regulo, C.; Roxburgh,
   I. W.; Salabert, D.; Stello, D.; Verner, G. A.; Belkacem, K.; Biazzo,
   K.; Cunha, M. S.; Gruberbauer, M.; Guzik, J. A.; Kupka, F.; Leroy,
   B.; Ludwig, H. -G.; Mathis, S.; Noels, A.; Noyes, R. W.; Roca Cortes,
   T.; Roth, M.; Sato, K. H.; Schmitt, J.; Suran, M. D.; Trampedach,
   R.; Uytterhoeven, K.; Ventura, R.
2010AN....331..972K    Altcode: 2010arXiv1005.0507K
  We report on the first asteroseismic analysis of solar-type stars
  observed by Kepler. Observations of three G-type stars, made at
  one-minute cadence during the first 33.5 days of science operations,
  reveal high signal-to-noise solar-like oscillation spectra in all three
  stars: About 20 modes of oscillation can clearly be distinguished
  in each star. We discuss the appearance of the oscillation spectra,
  including the presence of a possible signature of faculae, and the
  presence of mixed modes in one of the three stars.

---------------------------------------------------------
Title: Turbulent eddy-time-correlation in the solar convective zone
Authors: Belkacem, K.; Samadi, R.; Goupil, M. J.; Baudin, F.; Salabert,
   D.; Appourchaux, T.
2010A&A...522L...2B    Altcode: 2010arXiv1010.2682B
  Theoretical modeling of the driving processes of solar-like oscillations
  is a powerful way of understanding the properties of the convective
  zones of solar-type stars. In this framework, the description of the
  temporal correlation between turbulent eddies is an essential ingredient
  to model mode amplitudes. However, there is a debate between a Gaussian
  or Lorentzian description of the eddy-time correlation function
  (Samadi et al. 2003b, A&amp;A, 403, 303; Chaplin et al. 2005, MNRAS,
  360, 859). Indeed, a Gaussian description reproduces the low-frequency
  shape of the mode amplitude for the Sun, but is unsatisfactory from a
  theoretical point of view (Houdek 2010, Ap&amp;SS, 328, 237) and leads
  to other disagreements with observations (Samadi et al. 2007, A&amp;A,
  463, 297). These are solved by using a Lorentzian description, but
  there the low-frequency shape of the solar observations is not correctly
  reproduced. We reconcile the two descriptions by adopting the sweeping
  approximation, which consists in assuming that the eddy-time-correlation
  function is dominated by the advection of eddies, in the inertial range,
  by energy-bearing eddies. Using a Lorentzian function together with a
  cut-off frequency derived from the sweeping assumption allows us to
  reproduce the low-frequency shape of the observations. This result
  also constitutes a validation of the sweeping assumption for highly
  turbulent flows as in the solar case.

---------------------------------------------------------
Title: A Precise Asteroseismic Age and Radius for the Evolved Sun-like
    Star KIC 11026764
Authors: Metcalfe, T. S.; Monteiro, M. J. P. F. G.; Thompson, M. J.;
   Molenda-Żakowicz, J.; Appourchaux, T.; Chaplin, W. J.; Doǧan, G.;
   Eggenberger, P.; Bedding, T. R.; Bruntt, H.; Creevey, O. L.; Quirion,
   P. -O.; Stello, D.; Bonanno, A.; Silva Aguirre, V.; Basu, S.; Esch,
   L.; Gai, N.; Di Mauro, M. P.; Kosovichev, A. G.; Kitiashvili, I. N.;
   Suárez, J. C.; Moya, A.; Piau, L.; García, R. A.; Marques, J. P.;
   Frasca, A.; Biazzo, K.; Sousa, S. G.; Dreizler, S.; Bazot, M.; Karoff,
   C.; Frandsen, S.; Wilson, P. A.; Brown, T. M.; Christensen-Dalsgaard,
   J.; Gilliland, R. L.; Kjeldsen, H.; Campante, T. L.; Fletcher, S. T.;
   Handberg, R.; Régulo, C.; Salabert, D.; Schou, J.; Verner, G. A.;
   Ballot, J.; Broomhall, A. -M.; Elsworth, Y.; Hekker, S.; Huber, D.;
   Mathur, S.; New, R.; Roxburgh, I. W.; Sato, K. H.; White, T. R.;
   Borucki, W. J.; Koch, D. G.; Jenkins, J. M.
2010ApJ...723.1583M    Altcode: 2010arXiv1010.4329M
  The primary science goal of the Kepler Mission is to provide
  a census of exoplanets in the solar neighborhood, including the
  identification and characterization of habitable Earth-like planets. The
  asteroseismic capabilities of the mission are being used to determine
  precise radii and ages for the target stars from their solar-like
  oscillations. Chaplin et al. published observations of three bright
  G-type stars, which were monitored during the first 33.5 days of science
  operations. One of these stars, the subgiant KIC 11026764, exhibits a
  characteristic pattern of oscillation frequencies suggesting that it
  has evolved significantly. We have derived asteroseismic estimates of
  the properties of KIC 11026764 from Kepler photometry combined with
  ground-based spectroscopic data. We present the results of detailed
  modeling for this star, employing a variety of independent codes and
  analyses that attempt to match the asteroseismic and spectroscopic
  constraints simultaneously. We determine both the radius and the age
  of KIC 11026764 with a precision near 1%, and an accuracy near 2%
  for the radius and 15% for the age. Continued observations of this
  star promise to reveal additional oscillation frequencies that will
  further improve the determination of its fundamental properties.

---------------------------------------------------------
Title: A comparison of frequentist and Bayesian inference: searching
    for low-frequency p modes and g modes in Sun-as-a-star data
Authors: Broomhall, A. -M.; Chaplin, W. J.; Elsworth, Y.; Appourchaux,
   T.; New, R.
2010MNRAS.406..767B    Altcode: 2010MNRAS.tmp..680B; 2010arXiv1004.4505B
  We describe and use two different statistical approaches to
  try and detect low-frequency solar oscillations in Sun-as-a-star
  data: a frequentist approach and a Bayesian approach. We have used
  frequentist statistics to search contemporaneous Sun-as-a-star data
  for coincident, statistically prominent features. However, we find
  that this approach leads to numerous false detections. We have also
  used Bayesian statistics to search for evidence of low-frequency p
  modes and g modes in Sun-as-a-star data. We describe how Bayesian
  statistics can be used to search near-contemporaneous data for
  coincident prominent features. Near-contemporaneous data were
  used to circumvent the difficulties in deriving probabilities that
  occur when common noise is present in the data. We find that the
  Bayesian approach, which is reliant on the assumptions made when
  determining the posterior probability, leads to significantly fewer
  false detections and those that are observed can be discredited using
  a priori knowledge. Therefore, we have more confidence in the mode
  candidates found with Bayesian statistics.

---------------------------------------------------------
Title: Possible detection of phase changes from the non-transiting
    planet HD 46375b by CoRoT
Authors: Gaulme, P.; Vannier, M.; Guillot, T.; Mosser, B.; Mary,
   D.; Weiss, W. W.; Schmider, F. -X.; Bourguignon, S.; Deeg, H. J.;
   Régulo, C.; Aigrain, S.; Schneider, J.; Bruntt, H.; Deheuvels, S.;
   Donati, J. -F.; Appourchaux, T.; Auvergne, M.; Baglin, A.; Baudin,
   F.; Catala, C.; Michel, E.; Samadi, R.
2010A&A...518L.153G    Altcode: 2010arXiv1011.2690G
  Context. The present work deals with the detection of phase changes
  in an exoplanetary system. HD 46375 is a solar analog known to host
  a non-transiting Saturn-mass exoplanet with a 3.0236 day period. It
  was observed by the CoRoT satellite for 34 days during the fall of
  2008. <BR /> Aims: We attempt to identify at optical wavelengths,
  the changing phases of the planet as it orbits its star. We then
  try to improve the star model by means of a seismic analysis of the
  same light curve and the use of ground-based spectropolarimetric
  observations. <BR /> Methods: The data analysis relies on the Fourier
  spectrum and the folding of the time series. <BR /> Results: We find
  evidence of a sinusoidal signal compatible in terms of both amplitude
  and phase with light reflected by the planet. Its relative amplitude
  is Δ F<SUB>p</SUB>/F<SUB>star</SUB> = [13.0, 26.8] ppm, implying an
  albedo A = [0.16, 0.33] or a dayside visible brightness temperature
  T<SUB>b</SUB> ≃ [1880, 2030] K by assuming a radius R = 1.1
  R<SUB>Jup</SUB> and an inclination i = 45°. Its orbital phase differs
  from that of the radial-velocity signal by at most 2 σ_RV. However,
  the tiny planetary signal is strongly blended by another signal, which
  we attribute to a telluric signal with a 1 day period. We show that
  this signal is suppressed, but not eliminated, when using the time
  series for HD 46179 from the same CoRoT run as a reference. <BR />
  Conclusions: This detection of reflected light from a non-transiting
  planet should be confirmable with a longer CoRoT observation of the
  same field. In any case, it demonstrates that non-transiting planets
  can be characterized using ultra-precise photometric lightcurves
  with present-day observations by CoRoT and Kepler. The combined
  detection of solar-type oscillations on the same targets (Gaulme et
  al. 2010a) highlights the overlap between exoplanetary science and
  asteroseismology and shows the high potential of a mission such as
  Plato. <P />The CoRoT space mission, launched on 2006 December 27,
  was developed and is operated by the CNES, with participation of
  the Science Programs of ESA, ESA's RSSD, Austria, Belgium, Brazil,
  Germany and Spain.Figure 6 is only available in electronic form at
  <A href="http://www.aanda.org">http://www.aanda.org</A>

---------------------------------------------------------
Title: The solar-like CoRoT target HD 170987: spectroscopic and
    seismic observations
Authors: Mathur, S.; García, R. A.; Catala, C.; Bruntt, H.; Mosser,
   B.; Appourchaux, T.; Ballot, J.; Creevey, O. L.; Gaulme, P.; Hekker,
   S.; Huber, D.; Karoff, C.; Piau, L.; Régulo, C.; Roxburgh, I. W.;
   Salabert, D.; Verner, G. A.; Auvergne, M.; Baglin, A.; Chaplin, W. J.;
   Elsworth, Y.; Michel, E.; Samadi, R.; Sato, K.; Stello, D.
2010A&A...518A..53M    Altcode: 2010arXiv1004.4891M
  Context. The CoRoT mission is in its third year of observation and the
  data from the second long run in the galactic centre direction are being
  analysed. The solar-like oscillating stars that have been observed up
  to now have given some interesting results, specially concerning the
  amplitudes that are lower than predicted. We present here the results
  from the analysis of the star HD 170987. <BR /> Aims: The goal of this
  research work is to characterise the global parameters of HD 170987. We
  look for global seismic parameters such as the mean large separation,
  maximum amplitude of the modes, and surface rotation because the
  signal-to-noise ratio in the observations does not allow us to measure
  individual modes. We also aim to retrieve the parameters of the star
  and its chemical composition. <BR /> Methods: We studied the chemical
  composition of the star through ground-based observations performed
  with the NARVAL spectrograph. We used several methods to calculate
  the global parameters from the acoustic oscillations based on CoRoT
  data. The light curve of the star has been interpolated with inpainting
  algorithms to reduce the effect of data gaps. <BR /> Results: We found
  the power excess related to p modes in the range [400-1200] μHz with
  a mean large separation of 55.2 ± 0.8 μHz with a probability above
  95 % that increases to 55.9 ± 0.2 μHz in a higher frequency range
  [500-1250] μHz and a rejection level of 1%. A hint of the variation of
  this quantity with frequency was also found. The rotation period of the
  star is estimated to be around 4.3 days with an inclination axis of i =
  50° <SUP>+20</SUP><SUB>-13</SUB>. We measured a bolometric amplitude
  per radial mode in a range [2.4-2.9] ppm around 1000 μHz. Finally
  we estimate the stellar mass with a grid of models, M = 1.43 ± 0.05
  M_⊙, the radius, R = 1.96 ± 0.046 R_⊙, and the age ~2.4 Gyr. <P
  />The CoRoT space mission, launched on 2006 December 27, has been
  developed and is operated by CNES, with the contribution of Austria,
  Belgium, Brazil, ESA (RSSD and Science Programme), Germany and Spain.

---------------------------------------------------------
Title: The technical challenges of the Solar-Orbiter EUI instrument
Authors: Halain, Jean-Philippe; Rochus, Pierre; Appourchaux, Thierry;
   Berghmans, David; Harra, Louise; Schühle, Udo; Auchère, Frédéric;
   Zhukov, Andrei; Renotte, Etienne; Defise, Jean-Marc; Rossi, Laurence;
   Fleury-Frenette, Karl; Jacques, Lionel; Hochedez, Jean-François;
   Ben Moussa, Ali
2010SPIE.7732E..0RH    Altcode: 2010SPIE.7732E..20H
  The Extreme Ultraviolet Imager (EUI) onboard Solar Orbiter consists of
  a suite of two high-resolution imagers (HRI) and one dual-band full
  Sun imager (FSI) that will provide EUV and Lyman-α images of the
  solar atmospheric layers above the photosphere. The EUI instrument is
  based on a set of challenging new technologies allowing to reach the
  scientific objectives and to cope with the hard space environment of
  the Solar Orbiter mission. The mechanical concept of the EUI instrument
  is based on a common structure supporting the HRI and FSI channels,
  and a separated electronic box. A heat rejection baffle system is
  used to reduce the Sun heat load and provide a first protection level
  against the solar disk straylight. The spectral bands are selected by
  thin filters and multilayer mirror coatings. The detectors are 10μm
  pitch back illuminated CMOS Active Pixel Sensors (APS), best suited
  for the EUI science requirements and radiation hardness. This paper
  presents the EUI instrument concept and its major sub-systems. The
  current developments of the instrument technologies are also summarized.

---------------------------------------------------------
Title: Definition of an imaging spectrometer meeting the needs of
    UV solar physics
Authors: Ruiz de Galarreta Fanjul, C.; Philippon, A.; Vial, J. -C.;
   Lemaire, P.; Maillard, J. -P.; Buisset, C.; Appourchaux, T.;
   Auchère, F.
2010SPIE.7732E..36R    Altcode: 2010SPIE.7732E..99R
  The study of the outer solar atmosphere requires combining imaging
  and spectroscopy in the UV lines formed in the high chromosphere,
  the transition region and the corona. We start from the science
  requirements and we define the instrumental specifications in terms
  of field-of-view (FOV), spatial, temporal and spectral resolution and
  bandpass. We propose two different all-reflection optical architectures
  based on interferometric techniques: Spatial Heterodyne Spectroscopy
  (SHS); and Imaging Transform Spectrometer (IFTS). We describe the
  different set-ups and compare the potential performances of the two
  types of solutions, and discuss their feasibility. We conclude that
  IFTS appears to be the best solution, meeting the needs of UV solar
  physics. However, we point out the many difficulties to be encountered,
  especially as far as metrology is concerned.

---------------------------------------------------------
Title: Seismic and spectroscopic characterization of the solar-like
    pulsating CoRoT target HD 49385
Authors: Deheuvels, S.; Bruntt, H.; Michel, E.; Barban, C.; Verner,
   G.; Régulo, C.; Mosser, B.; Mathur, S.; Gaulme, P.; Garcia, R. A.;
   Boumier, P.; Appourchaux, T.; Samadi, R.; Catala, C.; Baudin, F.;
   Baglin, A.; Auvergne, M.; Roxburgh, I. W.; Pérez Hernández, F.
2010A&A...515A..87D    Altcode: 2010arXiv1003.4368D
  Context. The star HD 49385 is the first G-type solar-like pulsator
  observed in the seismology field of the space telescope CoRoT. The
  satellite collected 137 days of high-precision photometric data on
  this star, confirming that it presents solar-like oscillations. HD
  49385 was also observed in spectroscopy with the NARVAL spectrograph in
  January 2009. <BR /> Aims: Our goal is to characterize HD 49385 using
  both spectroscopic and seismic data. <BR /> Methods: The fundamental
  stellar parameters of HD 49385 are derived with the semi-automatic
  software VWA, and the projected rotational velocity is estimated by
  fitting synthetic profiles to isolated lines in the observed spectrum. A
  maximum likelihood estimation is used to determine the parameters of
  the observed p modes. We perform a global fit, in which modes are fitted
  simultaneously over nine radial orders, with degrees ranging from ℓ =
  0 to ℓ = 3 (36 individual modes). <BR /> Results: Precise estimates of
  the atmospheric parameters (T<SUB>eff</SUB>, [M/H], log g) and of the ν
  sin i of HD 49385 are obtained. The seismic analysis of the star leads
  to a clear identification of the modes for degrees ℓ = 0,1,2. Around
  the maximum of the signal (ν ≃ 1013 μHz), some peaks are found
  significant and compatible with the expected characteristics of ℓ =
  3 modes. Our fit yields robust estimates of the frequencies, linewidths
  and amplitudes of the modes. We find amplitudes of ~5.6 ± 0.8 ppm for
  radial modes at the maximum of the signal. The lifetimes of the modes
  range from one day (at high frequency) to a bit more than two days
  (at low frequency). Significant peaks are found outside the identified
  ridges and are fitted. They are attributed to mixed modes. <P />Based
  on data obtained from the CoRoT (Convection, Rotation and planetary
  Transits) space mission, developed by the French Space agency CNES
  in collaboration with the Science Programs of ESA, Austria, Belgium,
  Brazil, Germany and Spain.Based on data obtained using the Télescope
  Bernard Lyot at Observatoire du Pic du Midi, CNRS and Université Paul
  Sabatier, France.

---------------------------------------------------------
Title: An automated pipeline for asteroseismology based on the
    autocorrelation of stellar time series
Authors: Mosser, Benoit; Appourchaux, Thierry
2010arXiv1006.5079M    Altcode:
  The autocorrelation of an asteroseismic time series has been identified
  as a powerful tool capable of providing measurements of the large
  frequency separations. The performance of this method has been assessed
  and quantified by Mosser &amp; Appourchaux (2009). We propose now an
  automated pipeline based on it and describe its performance.

---------------------------------------------------------
Title: A Multi-Site Campaign to Measure Solar-Like Oscillations in
    Procyon. II. Mode Frequencies
Authors: Bedding, Timothy R.; Kjeldsen, Hans; Campante, Tiago L.;
   Appourchaux, Thierry; Bonanno, Alfio; Chaplin, William J.; Garcia,
   Rafael A.; Martić, Milena; Mosser, Benoit; Butler, R. Paul; Bruntt,
   Hans; Kiss, László L.; O'Toole, Simon J.; Kambe, Eiji; Ando,
   Hiroyasu; Izumiura, Hideyuki; Sato, Bun'ei; Hartmann, Michael;
   Hatzes, Artie; Barban, Caroline; Berthomieu, Gabrielle; Michel,
   Eric; Provost, Janine; Turck-Chièze, Sylvaine; Lebrun, Jean-Claude;
   Schmitt, Jerome; Bertaux, Jean-Loup; Benatti, Serena; Claudi, Riccardo
   U.; Cosentino, Rosario; Leccia, Silvio; Frandsen, Søren; Brogaard,
   Karsten; Glowienka, Lars; Grundahl, Frank; Stempels, Eric; Arentoft,
   Torben; Bazot, Michaël; Christensen-Dalsgaard, Jørgen; Dall, Thomas
   H.; Karoff, Christoffer; Lundgreen-Nielsen, Jens; Carrier, Fabien;
   Eggenberger, Patrick; Sosnowska, Danuta; Wittenmyer, Robert A.; Endl,
   Michael; Metcalfe, Travis S.; Hekker, Saskia; Reffert, Sabine
2010ApJ...713..935B    Altcode: 2010arXiv1003.0052B
  We have analyzed data from a multi-site campaign to observe oscillations
  in the F5 star Procyon. The data consist of high-precision velocities
  that we obtained over more than three weeks with 11 telescopes. A
  new method for adjusting the data weights allows us to suppress the
  sidelobes in the power spectrum. Stacking the power spectrum in a
  so-called échelle diagram reveals two clear ridges, which we identify
  with even and odd values of the angular degree (l = 0 and 2, and l =
  1 and 3, respectively). We interpret a strong, narrow peak at 446 μHz
  that lies close to the l = 1 ridge as a mode with mixed character. We
  show that the frequencies of the ridge centroids and their separations
  are useful diagnostics for asteroseismology. In particular, variations
  in the large separation appear to indicate a glitch in the sound-speed
  profile at an acoustic depth of ~1000 s. We list frequencies for 55
  modes extracted from the data spanning 20 radial orders, a range
  comparable to the best solar data, which will provide valuable
  constraints for theoretical models. A preliminary comparison with
  published models shows that the offset between observed and calculated
  frequencies for the radial modes is very different for Procyon than
  for the Sun and other cool stars. We find the mean lifetime of the
  modes in Procyon to be 1.29<SUP>+0.55</SUP> <SUB>-0.49</SUB> days,
  which is significantly shorter than the 2-4 days seen in the Sun.

---------------------------------------------------------
Title: The Asteroseismic Potential of Kepler: First Results for
    Solar-Type Stars
Authors: Chaplin, W. J.; Appourchaux, T.; Elsworth, Y.; García,
   R. A.; Houdek, G.; Karoff, C.; Metcalfe, T. S.; Molenda-Żakowicz,
   J.; Monteiro, M. J. P. F. G.; Thompson, M. J.; Brown, T. M.;
   Christensen-Dalsgaard, J.; Gilliland, R. L.; Kjeldsen, H.; Borucki,
   W. J.; Koch, D.; Jenkins, J. M.; Ballot, J.; Basu, S.; Bazot, M.;
   Bedding, T. R.; Benomar, O.; Bonanno, A.; Brandão, I. M.; Bruntt,
   H.; Campante, T. L.; Creevey, O. L.; Di Mauro, M. P.; Doǧan,
   G.; Dreizler, S.; Eggenberger, P.; Esch, L.; Fletcher, S. T.;
   Frandsen, S.; Gai, N.; Gaulme, P.; Handberg, R.; Hekker, S.; Howe,
   R.; Huber, D.; Korzennik, S. G.; Lebrun, J. C.; Leccia, S.; Martic,
   M.; Mathur, S.; Mosser, B.; New, R.; Quirion, P. -O.; Régulo, C.;
   Roxburgh, I. W.; Salabert, D.; Schou, J.; Sousa, S. G.; Stello, D.;
   Verner, G. A.; Arentoft, T.; Barban, C.; Belkacem, K.; Benatti, S.;
   Biazzo, K.; Boumier, P.; Bradley, P. A.; Broomhall, A. -M.; Buzasi,
   D. L.; Claudi, R. U.; Cunha, M. S.; D'Antona, F.; Deheuvels, S.;
   Derekas, A.; García Hernández, A.; Giampapa, M. S.; Goupil, M. J.;
   Gruberbauer, M.; Guzik, J. A.; Hale, S. J.; Ireland, M. J.; Kiss,
   L. L.; Kitiashvili, I. N.; Kolenberg, K.; Korhonen, H.; Kosovichev,
   A. G.; Kupka, F.; Lebreton, Y.; Leroy, B.; Ludwig, H. -G.; Mathis, S.;
   Michel, E.; Miglio, A.; Montalbán, J.; Moya, A.; Noels, A.; Noyes,
   R. W.; Pallé, P. L.; Piau, L.; Preston, H. L.; Roca Cortés, T.;
   Roth, M.; Sato, K. H.; Schmitt, J.; Serenelli, A. M.; Silva Aguirre,
   V.; Stevens, I. R.; Suárez, J. C.; Suran, M. D.; Trampedach, R.;
   Turck-Chièze, S.; Uytterhoeven, K.; Ventura, R.; Wilson, P. A.
2010ApJ...713L.169C    Altcode: 2010arXiv1001.0506C
  We present preliminary asteroseismic results from Kepler on three G-type
  stars. The observations, made at one-minute cadence during the first
  33.5 days of science operations, reveal high signal-to-noise solar-like
  oscillation spectra in all three stars: about 20 modes of oscillation
  may be clearly distinguished in each star. We discuss the appearance of
  the oscillation spectra, use the frequencies and frequency separations
  to provide first results on the radii, masses, and ages of the stars,
  and comment in the light of these results on prospects for inference
  on other solar-type stars that Kepler will observe.

---------------------------------------------------------
Title: Kepler Asteroseismology Program: Introduction and First Results
Authors: Gilliland, Ronald L.; Brown, Timothy M.;
   Christensen-Dalsgaard, Jørgen; Kjeldsen, Hans; Aerts, Conny;
   Appourchaux, Thierry; Basu, Sarbani; Bedding, Timothy R.; Chaplin,
   William J.; Cunha, Margarida S.; De Cat, Peter; De Ridder, Joris;
   Guzik, Joyce A.; Handler, Gerald; Kawaler, Steven; Kiss, László;
   Kolenberg, Katrien; Kurtz, Donald W.; Metcalfe, Travis S.; Monteiro,
   Mario J. P. F. G.; Szabó, Robert; Arentoft, Torben; Balona, Luis;
   Debosscher, Jonas; Elsworth, Yvonne P.; Quirion, Pierre-Olivier;
   Stello, Dennis; Suárez, Juan Carlos; Borucki, William J.; Jenkins,
   Jon M.; Koch, David; Kondo, Yoji; Latham, David W.; Rowe, Jason F.;
   Steffen, Jason H.
2010PASP..122..131G    Altcode: 2010arXiv1001.0139G
  Asteroseismology involves probing the interiors of stars and quantifying
  their global properties, such as radius and age, through observations of
  normal modes of oscillation. The technical requirements for conducting
  asteroseismology include ultrahigh precision measured in photometry
  in parts per million, as well as nearly continuous time series over
  weeks to years, and cadences rapid enough to sample oscillations with
  periods as short as a few minutes. We report on results from the first
  43 days of observations, in which the unique capabilities of Kepler
  in providing a revolutionary advance in asteroseismology are already
  well in evidence. The Kepler asteroseismology program holds intrinsic
  importance in supporting the core planetary search program through
  greatly enhanced knowledge of host star properties, and extends well
  beyond this to rich applications in stellar astrophysics.

---------------------------------------------------------
Title: The quest for the solar g modes
Authors: Appourchaux, T.; Belkacem, K.; Broomhall, A. -M.; Chaplin,
   W. J.; Gough, D. O.; Houdek, G.; Provost, J.; Baudin, F.; Boumier,
   P.; Elsworth, Y.; García, R. A.; Andersen, B. N.; Finsterle, W.;
   Fröhlich, C.; Gabriel, A.; Grec, G.; Jiménez, A.; Kosovichev, A.;
   Sekii, T.; Toutain, T.; Turck-Chièze, S.
2010A&ARv..18..197A    Altcode: 2010A&ARv.tmp....1A; 2009arXiv0910.0848A
  Solar gravity modes (or g modes)—oscillations of the solar interior
  on which buoyancy acts as the restoring force—have the potential
  to provide unprecedented inference on the structure and dynamics of
  the solar core, inference that is not possible with the well-observed
  acoustic modes (or p modes). The relative high amplitude of the g-mode
  eigenfunctions in the core and the evanesence of the modes in the
  convection zone make the modes particularly sensitive to the physical
  and dynamical conditions in the core. Owing to the existence of the
  convection zone, the g modes have very low amplitudes at photospheric
  levels, which makes the modes extremely hard to detect. In this article,
  we review the current state of play regarding attempts to detect g
  modes. We review the theory of g modes, including theoretical estimation
  of the g-mode frequencies, amplitudes and damping rates. Then we go
  on to discuss the techniques that have been used to try to detect g
  modes. We review results in the literature, and finish by looking to
  the future, and the potential advances that can be made—from both
  data and data-analysis perspectives—to give unambiguous detections
  of individual g modes. The review ends by concluding that, at the time
  of writing, there is indeed a consensus amongst the authors that there
  is currently no undisputed detection of solar g modes.

---------------------------------------------------------
Title: The CoRoT target HD 49933 . II. Comparison of theoretical
    mode amplitudes with observations
Authors: Samadi, R.; Ludwig, H. -G.; Belkacem, K.; Goupil, M. J.;
   Benomar, O.; Mosser, B.; Dupret, M. -A.; Baudin, F.; Appourchaux,
   T.; Michel, E.
2010A&A...509A..16S    Altcode: 2009arXiv0910.4037S
  Context. The seismic data obtained by CoRoT for the star HD 49933 enable
  us for the first time to measure directly the amplitudes and linewidths
  of solar-like oscillations for a star other than the Sun. From those
  measurements it is possible, as was done for the Sun, to constrain
  models of the excitation of acoustic modes by turbulent convection. <BR
  /> Aims: We compare a stochastic excitation model described in Paper
  I with the asteroseismology data for HD 49933, a star that is rather
  metal poor and significantly hotter than the Sun. <BR /> Methods:
  Using the seismic determinations of the mode linewidths detected by
  CoRoT for HD 49933 and the theoretical mode excitation rates computed
  in Paper I for the specific case of HD 49933, we derive the expected
  surface velocity amplitudes of the acoustic modes detected in HD
  49933. Using a calibrated quasi-adiabatic approximation relating
  the mode amplitudes in intensity to those in velocity, we derive the
  expected values of the mode amplitude in intensity. <BR /> Results:
  Except at rather high frequency, our amplitude calculations are within
  1-σ error bars of the mode surface velocity spectrum derived with
  the HARPS spectrograph. The same is found with respect to the mode
  amplitudes in intensity derived for HD 49933 from the CoRoT data. On
  the other hand, at high frequency (ν ⪆ 1.9 mHz), our calculations
  depart significantly from the CoRoT and HARPS measurements. We show
  that assuming a solar metal abundance rather than the actual metal
  abundance of the star would result in a larger discrepancy with the
  seismic data. Furthermore, we present calculations which assume the
  “new” solar chemical mixture to be in better agreement with the
  seismic data than those that assumed the “old” solar chemical
  mixture. <BR /> Conclusions: These results validate in the case of a
  star significantly hotter than the Sun and α Cen A the main assumptions
  in the model of stochastic excitation. However, the discrepancies seen
  at high frequency highlight some deficiencies of the modelling, whose
  origin remains to be understood. We also show that it is important
  to take the surface metal abundance of the solar-like pulsators into
  account. <P />The CoRoT space mission, launched on December 27 2006,
  has been developped and is operated by CNES, with the contribution of
  Austria, Belgium, Brasil, ESA, Germany and Spain.

---------------------------------------------------------
Title: SIAMOIS, asteroseismolgy at Dome C after CoRoT
Authors: Mosser, B.; Buey, T.; Appourchaux, T.; Charpinet, S.; Mathias,
   P.; Schmider, F. X.; Maillard, J. P.; Siamois Team
2010EAS....40..381M    Altcode:
  SIAMOIS is a ground-based asteroseismology project, to pursue velocity
  measurements from the Dome C Concordia station in Antarctica. Dome
  C appears to be the ideal place for ground-based asteroseismic
  observations as it is capable of delivering a duty cycle as high as
  87% during the three-month long polar night. This high duty cycle,
  a crucial point for asteroseismology, is comparable to the best
  space-borne observations. We present the quality of the SIAMOIS project,
  that yields to its selection as top priority by the working group of
  ARENA dedicated to “Time series observations from Dome C”. We
  show that, after CoRoT, SIAMOIS proposes a large scientific case,
  that extends the pioneering work and great discoveries of CoRoT. We
  depict a few important ingredients of the project: full automation,
  space-like philosophy, and compatibility with the current facilities at
  the Concordia station. SIAMOIS has no real competitor before at least
  2016/2017, and can be considered as a pathfinder for many important
  issues concerning astronomical observations at Dome C.

---------------------------------------------------------
Title: On detecting the large separation in the autocorrelation of
    stellar oscillation times series
Authors: Mosser, B.; Appourchaux, T.
2009A&A...508..877M    Altcode: 2009arXiv0909.0782M
  Context: The observations carried out by the space missions CoRoT
  and Kepler provide a large set of asteroseismic data. Their analysis
  requires an efficient procedure first to determine if a star reliably
  shows solar-like oscillations, second to measure the so-called large
  separation, third to estimate the asteroseismic information that can
  be retrieved from the Fourier spectrum.<BR /> Aims: In this paper we
  develop a procedure based on the autocorrelation of the seismic Fourier
  spectrum that is capable of providing measurements of the large and
  small frequency separations. The performance of the autocorrelation
  method needs to be assessed and quantified. We therefore searched
  for criteria able to predict the output that one can expect from the
  analysis by autocorrelation of a seismic time series. <BR /> Methods:
  First, the autocorrelation is properly scaled to take into account
  the contribution of white noise. Then we use the null hypothesis
  H<SUB>0</SUB> test to assess the reliability of the autocorrelation
  analysis. Calculations based on solar and CoRoT time series are
  performed to quantify the performance as a function of the amplitude
  of the autocorrelation signal.<BR /> Results: We obtain an empirical
  relation for the performance of the autocorrelation method. We show
  that the precision of the method increases with the observation
  length, and with the mean seismic amplitude-to-background ratio of
  the pressure modes to the power 1.5 ± 0.05. We propose an automated
  determination of the large separation, whose reliability is quantified
  by the H<SUB>0</SUB> test. We apply this method to analyze red giants
  observed by CoRoT. We estimate the expected performance for photometric
  time series of the Kepler mission. We demonstrate that the method
  makes it possible to distinguish ℓ = 0 from ℓ = 1 modes.<BR />
  Conclusions: The envelope autocorrelation function (EACF) has proven
  to be very powerful for the determination of the large separation
  in noisy asteroseismic data, since it enables us to quantify the
  precision of the performance of different measurements: mean large
  separation, variation of the large separation with frequency, small
  separation and degree identification. <P />The CoRoT space mission,
  launched on 2006 December 27, was developed and is operated by the
  CNES, with participation of the Science Programs of ESA, ESA's RSSD,
  Austria, Belgium, Brazil, Germany and Spain.

---------------------------------------------------------
Title: A fresh look at the seismic spectrum of HD49933: analysis of
    180 days of CoRoT photometry
Authors: Benomar, O.; Baudin, F.; Campante, T. L.; Chaplin, W. J.;
   García, R. A.; Gaulme, P.; Toutain, T.; Verner, G. A.; Appourchaux,
   T.; Ballot, J.; Barban, C.; Elsworth, Y.; Mathur, S.; Mosser, B.;
   Régulo, C.; Roxburgh, I. W.; Auvergne, M.; Baglin, A.; Catala, C.;
   Michel, E.; Samadi, R.
2009A&A...507L..13B    Altcode: 2009arXiv0910.3060B
  Context: Solar-like oscillations have now been observed in several
  stars, thanks to ground-based spectroscopic observations and space-borne
  photometry. CoRoT, which has been in orbit since December 2006, has
  observed the star HD49933 twice. The oscillation spectrum of this
  star has proven difficult to interpret. <BR />Aims: Thanks to a new
  timeseries provided by CoRoT, we aim to provide a robust description
  of the oscillations in HD49933, i.e., to identify the degrees of the
  observed modes, and to measure mode frequencies, widths, amplitudes
  and the average rotational splitting. <BR />Methods: Several methods
  were used to model the Fourier spectrum: Maximum Likelihood Estimators
  and Bayesian analysis using Markov Chain Monte-Carlo techniques. <BR
  />Results: The different methods yield consistent result, and allow us
  to make a robust identification of the modes and to extract precise
  mode parameters. Only the rotational splitting remains difficult to
  estimate precisely, but is clearly relatively large (several μHz in
  size). <P />The CoRoT space mission, launched on 2006 December 27,
  was developed and is operated by the CNES, with participation of
  the Science Programs of ESA, ESA's RSSD, Austria, Belgium, Brazil,
  Germany and Spain. <P />Figures 5-9 and Table 2 are only available in
  electronic form at http://www.aanda.org

---------------------------------------------------------
Title: The solar-like oscillations of HD 49933: a Bayesian approach
Authors: Benomar, O.; Appourchaux, T.; Baudin, F.
2009A&A...506...15B    Altcode:
  Context: Asteroseismology has entered a new era with the availability
  of continuous observations from space-borne missions such as MOST,
  CoRoT and Kepler. However, the low amplitude and the complexity
  of the observed spectrum make the exploitation of these data sets
  difficult. <BR />Aims: The use of robust methods to estimate the
  parameters of stellar oscillation eigenmodes is necessary to fully
  exploit these new data sets. These parameters include in particular
  the frequency, the width and the energy of the eigenmodes, all
  being required for a seismic interpretation of the stellar internal
  structure or excitation of the eigenmodes. <BR />Methods: A Bayesian
  approach, coupled with a Markov chain Monte Carlo (MCMC) algorithm, is
  presented. Such a method allows the use of a priori knowledge to improve
  the parameter estimation. It also provides complete information on the
  probability distribution of the fitted parameters. The method is tested
  on simulated time series and then applied to CoRoT observations of HD
  49933. <BR />Results: The simulated time series allow the validation
  of the method for conditions similar to those of the observations in
  terms of spectral complexity and signal-to-noise ratio. However, a very
  important problem in the analysis of the HD 49933 mode spectrum is the
  l degree identification of the modes. The degree identification has
  little impact on the large frequency separation, rotational splitting,
  energy and width estimation, whereas individual frequencies and the star
  inclination angle evaluation are strongly affected. From a statistical
  point of view, we provide a quantitative ranking of the four models
  considered. The most probable model includes only modes of degree 0
  and 1. Two other models include modes with degree up to 2 and have a
  non negligible level of significance. The last model includes modes of
  degree 0 and 1 but has an alternate degree identification and can be
  definitively rejected. In conclusion, the significance of the resulting
  probabilities is not sufficient to draw a definite conclusion. <P />The
  CoRoT space mission, launched on <P />2006 December 27, was developed
  and is operated by the CNES, with <P />participation of the Science
  Programs of ESA, ESA's RSSD, Austria, <P />Belgium, Brazil, Germany
  and Spain. <P />Tables 10 to 15 and Figs. 11, 12 are only available
  in electronic form at http://www.aanda.org

---------------------------------------------------------
Title: The CoRoT target HD 175726: an active star with weak solar-like
    oscillations
Authors: Mosser, B.; Michel, E.; Appourchaux, T.; Barban, C.; Baudin,
   F.; Boumier, P.; Bruntt, H.; Catala, C.; Deheuvels, S.; García,
   R. A.; Gaulme, P.; Regulo, C.; Roxburgh, I.; Samadi, R.; Verner, G.;
   Auvergne, M.; Baglin, A.; Ballot, J.; Benomar, O.; Mathur, S.
2009A&A...506...33M    Altcode: 2009arXiv0908.2244M
  Context: The CoRoT short runs give us the opportunity to observe a large
  variety of late-type stars through their solar-like oscillations. We
  report observations of the star HD 175726 that lasted for 27 days
  during the first short run of the mission. The time series reveals a
  high-activity signal and the power spectrum presents an excess due to
  solar-like oscillations with a low signal-to-noise ratio. <BR />Aims:
  Our aim is to identify the most efficient tools to extract as much
  information as possible from the power density spectrum. <BR />Methods:
  The most productive method appears to be the autocorrelation of the
  time series, calculated as the spectrum of the filtered spectrum. This
  method is efficient, very rapid computationally, and will be useful for
  the analysis of other targets, observed with CoRoT or with forthcoming
  missions such as Kepler and Plato. <BR />Results: The mean large
  separation has been measured to be 97.2±0.5 μHz, slightly below the
  expected value determined from solar scaling laws. We also show strong
  evidence for variation of the large separation with frequency. The
  bolometric mode amplitude is only 1.7±0.25 ppm for radial modes, which
  is 1.7 times less than expected. Due to the low signal-to-noise ratio,
  mode identification is not possible for the available data set of HD
  175726. <P />The CoRoT space mission, launched on 2006 December 27, was
  developed and is operated by the CNES, with participation of the Science
  Programs of ESA, ESAs RSSD, Austria, Belgium, Brazil, Germany and Spain.

---------------------------------------------------------
Title: Mode width fitting with a simple Bayesian approach. Application
    to CoRoT targets HD 181420 and HD 49933
Authors: Gaulme, P.; Appourchaux, T.; Boumier, P.
2009A&A...506....7G    Altcode: 2010arXiv1011.2675G
  Aims: We investigate the asteroseismology of two solar-like targets as
  observed with the CoRoT satellite, with particular attention paid to
  the mode fitting. HD 181420 and HD 49933 are typical CoRoT solar-like
  targets (156 and 60-day runs). The low signal-to-noise ratio (SNR) of
  about 3{-}10 prevents us from unambiguously identifying the individual
  oscillation modes. In particular, convergence problems appear at the
  edges of the oscillation spectrum. <BR />Methods: We apply a Bayesian
  approach to the analysis of these data. We compare the global fitting
  of the power spectra obtained by the classical maximum likelihood
  (MLE) and the maximum a posteriori (MAP) estimators. <BR />Results:
  We examine the impact of the choice of the priors upon the fitted
  parameters. We also propose to reduce the number of free parameters
  in the fitting, by replacing the individual estimate of mode height
  associated with each overtone by a continuous function of frequency
  (Gaussian profile). <BR />Conclusions: The MAP appears as a powerful
  tool to constrain the global fits, but it must be used carefully and
  only with reliable priors. The mode width of the stars increases with
  the frequency over all the oscillation spectrum. <P />The CoRoT space
  mission, launched on 2006 December 27, was developed and is operated
  by the CNES, with participation of the Science Programs of ESA, ESA's
  RSSD, Austria, Belgium, Brazil, Germany and Spain.

---------------------------------------------------------
Title: On posterior probability and significance level: application
    to the power spectrum of HD 49 933 observed by CoRoT
Authors: Appourchaux, T.; Samadi, R.; Dupret, M. -A.
2009A&A...506....1A    Altcode: 2009arXiv0906.0864A
  Context: The CoRoT mission provides asteroseismic data of very high
  quality allowing one to adopt new statistical approaches for mode
  detection in power spectra, especially with respect to testing the
  null hypothesis (H{0}, which assumes that what is observed is pure
  noise). <BR />Aims: We emphasize that the significance level when
  rejecting the null hypothesis can lead to the incorrect conclusion
  that the H{0} hypothesis is unlikely to occur at that significance
  level. We demonstrate that the significance level is unrelated to
  the posterior probability of H{0}, given the observed data set, and
  that this posterior probability is very much higher than implied
  by the significance level. <BR />Methods: We use Bayes theorem to
  derive the posterior probability of that H{0} is true assuming an
  alternative hypothesis H{1} that a mode is present, taking some prior
  for the mode height, mode amplitude and linewidth. <BR />Results: We
  compute the posterior probability of H{0} for the p modes detected on
  HD 49 933 by CoRoT. <BR />Conclusions: We conclude that the posterior
  probability of H{0} provide a much more conservative quantification
  of the mode detection than the significance level. This framework
  can be applied to any similar stellar power spectra obtained to
  complete asteroseismology. <P />The CoRoT space mission, launched
  on <P />2006 December 27, was developed and is operated by the CNES,
  with <P />participation of the Science Programs of ESA, ESA's RSSD,
  Austria, <P />Belgium, Brazil, Germany and Spain.

---------------------------------------------------------
Title: The CoRoT satellite in flight: description and performance
Authors: Auvergne, M.; Bodin, P.; Boisnard, L.; Buey, J. -T.;
   Chaintreuil, S.; Epstein, G.; Jouret, M.; Lam-Trong, T.; Levacher,
   P.; Magnan, A.; Perez, R.; Plasson, P.; Plesseria, J.; Peter, G.;
   Steller, M.; Tiphène, D.; Baglin, A.; Agogué, P.; Appourchaux,
   T.; Barbet, D.; Beaufort, T.; Bellenger, R.; Berlin, R.; Bernardi,
   P.; Blouin, D.; Boumier, P.; Bonneau, F.; Briet, R.; Butler, B.;
   Cautain, R.; Chiavassa, F.; Costes, V.; Cuvilho, J.; Cunha-Parro,
   V.; de Oliveira Fialho, F.; Decaudin, M.; Defise, J. -M.; Djalal, S.;
   Docclo, A.; Drummond, R.; Dupuis, O.; Exil, G.; Fauré, C.; Gaboriaud,
   A.; Gamet, P.; Gavalda, P.; Grolleau, E.; Gueguen, L.; Guivarc'h,
   V.; Guterman, P.; Hasiba, J.; Huntzinger, G.; Hustaix, H.; Imbert,
   C.; Jeanville, G.; Johlander, B.; Jorda, L.; Journoud, P.; Karioty,
   F.; Kerjean, L.; Lafond, L.; Lapeyrere, V.; Landiech, P.; Larqué,
   T.; Laudet, P.; Le Merrer, J.; Leporati, L.; Leruyet, B.; Levieuge,
   B.; Llebaria, A.; Martin, L.; Mazy, E.; Mesnager, J. -M.; Michel,
   J. -P.; Moalic, J. -P.; Monjoin, W.; Naudet, D.; Neukirchner, S.;
   Nguyen-Kim, K.; Ollivier, M.; Orcesi, J. -L.; Ottacher, H.; Oulali,
   A.; Parisot, J.; Perruchot, S.; Piacentino, A.; Pinheiro da Silva,
   L.; Platzer, J.; Pontet, B.; Pradines, A.; Quentin, C.; Rohbeck, U.;
   Rolland, G.; Rollenhagen, F.; Romagnan, R.; Russ, N.; Samadi, R.;
   Schmidt, R.; Schwartz, N.; Sebbag, I.; Smit, H.; Sunter, W.; Tello,
   M.; Toulouse, P.; Ulmer, B.; Vandermarcq, O.; Vergnault, E.; Wallner,
   R.; Waultier, G.; Zanatta, P.
2009A&A...506..411A    Altcode: 2009arXiv0901.2206A
  Context: CoRoT is a space telescope dedicated to stellar seismology
  and the search for extrasolar planets. The mission is led by the CNES
  in association with French laboratories and has a large international
  participation. The European Space Agency (ESA), Austria, Belgium, and
  Germany contribute to the payload, and Spain and Brazil contribute to
  the ground segment. Development of the spacecraft, which is based on a
  PROTEUS low earth orbit (LEO) recurrent platform, commenced in October
  2000, and the satellite was launched on December 27, 2006. <BR />Aims:
  The instrument and platform characteristics prior to launch have been
  described in ESA publication (SP-1306). In the present paper we explain
  the behaviour in flight, based on raw and corrected data. <BR />Methods:
  Five runs have been completed since January 2007. The data used here
  are essentially those acquired during the commissioning phase and from
  a long run that lasted 146 days. These enable us to give a complete
  overview of the instrument and platform behaviour for all environmental
  conditions. The ground based data processing is not described in detail
  because the most important method has been published elsewhere. <BR
  />Results: We show that the performance specifications are easily
  satisfied when the environmental conditions are favourable. Most of the
  perturbations, hence data corrections, are related to LEO perturbations:
  high energy particles inside the South Atlantic Anomaly (SAA), eclipses
  and temperature variations, and line of sight fluctuations due to the
  attitude control system. Straylight due to the reflected light from
  the earth, which is controlled by the telescope and baffle design,
  appears to be negligible. <P />The CoRoT space mission, launched on
  December 27th 2006, has been developed and is operated by CNES, with
  contributions from Austria, Belgium, Brazil, ESA, Germany and Spain. <P
  />Four French laboratories associated with the CNRS (LESIA, LAM, IAS,
  OMP) collaborate with CNES on the satellite development. The authors
  are grateful to Ian Roxburgh for a careful reading of the manuscript.

---------------------------------------------------------
Title: Hydrodynamical simulations of convection-related stellar
    micro-variability. II. The enigmatic granulation background of the
    CoRoT target HD 49933
Authors: Ludwig, H. -G.; Samadi, R.; Steffen, M.; Appourchaux, T.;
   Baudin, F.; Belkacem, K.; Boumier, P.; Goupil, M. -J.; Michel, E.
2009A&A...506..167L    Altcode: 2009arXiv0905.2695L
  Context: Local-box hydrodynamical model atmospheres provide
  statistical information about a star's emergent radiation field
  which allows one to predict the level of its granulation-related
  micro-variability. Space-based photometry is now sufficiently
  accurate to test model predictions. <BR />Aims: We aim to model the
  photometric granulation background of HD 49933 as well as the Sun,
  and compare the predictions to the measurements obtained by the
  &lt;sf&gt;CoRoT&lt;/sf&gt; and &lt;sf&gt;SOHO&lt;/sf&gt; satellite
  missions. <BR />Methods: We construct hydrodynamical model atmospheres
  representing HD 49933 and the Sun, and use a previously developed
  scaling technique to obtain the observable disk-integrated brightness
  fluctuations. We further performed exploratory magneto-hydrodynamical
  simulations to gauge the impact of small scale magnetic fields
  on the synthetic light-curves. <BR />Results: We find that the
  granulation-related brightness fluctuations depend on metallicity. We
  obtain a satisfactory correspondence between prediction and observation
  for the Sun, validating our approach. For HD 49933, we arrive at
  a significant over-estimation by a factor of two to three in total
  power. Locally generated magnetic fields are unlikely to be responsible,
  otherwise existing fields would need to be rather strong to sufficiently
  suppress the granulation signal. Presently suggested updates on the
  fundamental stellar parameters do not improve the correspondence;
  however, an ad-hoc increase of the HD 49933 surface gravity by about
  0.2 dex would eliminate most of the discrepancy. <BR />Conclusions:
  We diagnose a puzzling discrepancy between the predicted and observed
  granulation background in HD 49933, with only rather ad-hoc ideas for
  remedies at hand. <P />The &lt;sf&gt;CoRoT&lt;/sf&gt; space mission,
  launched on December 27th 2006, has been developed and is operated by
  CNES, with the contribution of Austria, Belgium, Brazil, ESA, Germany
  and Spain. CIFIST Marie Curie Excellence Team.

---------------------------------------------------------
Title: Solar-like oscillations in HD 181420: data analysis of 156
    days of CoRoT data
Authors: Barban, C.; Deheuvels, S.; Baudin, F.; Appourchaux, T.;
   Auvergne, M.; Ballot, J.; Boumier, P.; Chaplin, W. J.; García,
   R. A.; Gaulme, P.; Michel, E.; Mosser, B.; Régulo, C.; Roxburgh,
   I. W.; Verner, G.; Baglin, A.; Catala, C.; Samadi, R.; Bruntt, H.;
   Elsworth, Y.; Mathur, S.
2009A&A...506...51B    Altcode:
  Context: The estimate of solar-like oscillation properties, such
  as their frequencies, amplitudes and lifetimes, is challenging
  because of their low amplitudes and will benefit from long and
  uninterrupted observing runs. The space telescope CoRoT allows us
  to obtain high-performance photometric data over a long and quasi
  continuous period. Among its main targets are stars for which we expect
  solar-like oscillations. <BR />Aims: HD 181420, an F2 main sequence
  star, has been observed by CoRoT during its first long run covering
  about 156 days. With this unprecedently high-quality set of data,
  our aim is to derive the p-mode parameters that can be used to probe
  the stellar interior. <BR />Methods: The CoRoT data obtained on HD
  181420 is analysed using a classical Fourier approach for the search
  for the p mode signature. The p-mode parameters are then derived using
  global fitting of the power spectrum by a Lorentzian model, as used
  widely in the solar case. <BR />Results: From the p-mode frequencies,
  the mean value of the large spacing is estimated to be 75 {μ Hz}. The
  p-mode amplitudes are slightly less than 4 ppm with a line width of
  about 8 {μ Hz} at the maximum of the p modes. The inclination angle is
  estimated to be around 45 °. The large mode line-width combined with
  the observed mode spacing make it difficult to identify the ℓ=2 modes
  and to estimate the rotational splitting. We explore two scenarios
  for the identification of the modes. <P />The CoRoT space mission,
  launched on 2006 December 27, was delopped and is operated by the
  CNES with participation of the Science Programs of ESA; ESA's RSSD,
  Austria, Belgium, Brazil, Germany and Spain.

---------------------------------------------------------
Title: Solar-like oscillations with low amplitude in the CoRoT target
    HD 181906
Authors: García, R. A.; Régulo, C.; Samadi, R.; Ballot, J.; Barban,
   C.; Benomar, O.; Chaplin, W. J.; Gaulme, P.; Appourchaux, T.; Mathur,
   S.; Mosser, B.; Toutain, T.; Verner, G. A.; Auvergne, M.; Baglin,
   A.; Baudin, F.; Boumier, P.; Bruntt, H.; Catala, C.; Deheuvels, S.;
   Elsworth, Y.; Jiménez-Reyes, S. J.; Michel, E.; Pérez Hernández,
   F.; Roxburgh, I. W.; Salabert, D.
2009A&A...506...41G    Altcode: 2009arXiv0907.0608G
  Context: The F8 star HD 181906 (effective temperature ∼6300 K) was
  observed for 156 days by the CoRoT satellite during the first long
  run in the direction of the galactic centre. Analysis of the data
  reveals a spectrum of solar-like acoustic oscillations. However, the
  faintness of the target (m<SUB>v</SUB> = 7.65) means the signal-to-noise
  (S/N) in the acoustic modes is quite low, and this low S/N leads to
  complications in the analysis. <BR />Aims: We extract global variables
  of the star, as well as key parameters of the p modes observed in the
  power spectrum of the lightcurve. <BR />Methods: The power spectrum
  of the lightcurve, a wavelet transform and spot fitting were used
  to obtain the average rotation rate of the star and its inclination
  angle. Then, the autocorrelation of the power spectrum and the power
  spectrum of the power spectrum were used to properly determine the
  large separation. Finally, estimations of the mode parameters were
  done by maximizing the likelihood of a global fit, where several modes
  were fit simultaneously. <BR />Results: We have been able to infer the
  mean surface rotation rate of the star (~4 μHz) with indications of
  the presence of surface differential rotation, the large separation
  of the p modes (~87 μHz), hence also the “ridges” corresponding
  to overtones of the acoustic modes. <P />CoRoT (Convection, Rotation
  and planetary Transits) is a minisatellite developed by the French
  Space agency CNES in collaboration with the Science Programmes of ESA,
  Austria, Belgium, Brazil, Germany and Spain.

---------------------------------------------------------
Title: Transiting exoplanets from the CoRoT space
mission. VIII. CoRoT-7b: the first super-Earth with measured radius
Authors: Léger, A.; Rouan, D.; Schneider, J.; Barge, P.; Fridlund,
   M.; Samuel, B.; Ollivier, M.; Guenther, E.; Deleuil, M.; Deeg, H. J.;
   Auvergne, M.; Alonso, R.; Aigrain, S.; Alapini, A.; Almenara, J. M.;
   Baglin, A.; Barbieri, M.; Bruntt, H.; Bordé, P.; Bouchy, F.; Cabrera,
   J.; Catala, C.; Carone, L.; Carpano, S.; Csizmadia, Sz.; Dvorak,
   R.; Erikson, A.; Ferraz-Mello, S.; Foing, B.; Fressin, F.; Gandolfi,
   D.; Gillon, M.; Gondoin, Ph.; Grasset, O.; Guillot, T.; Hatzes, A.;
   Hébrard, G.; Jorda, L.; Lammer, H.; Llebaria, A.; Loeillet, B.;
   Mayor, M.; Mazeh, T.; Moutou, C.; Pätzold, M.; Pont, F.; Queloz, D.;
   Rauer, H.; Renner, S.; Samadi, R.; Shporer, A.; Sotin, Ch.; Tingley,
   B.; Wuchterl, G.; Adda, M.; Agogu, P.; Appourchaux, T.; Ballans, H.;
   Baron, P.; Beaufort, T.; Bellenger, R.; Berlin, R.; Bernardi, P.;
   Blouin, D.; Baudin, F.; Bodin, P.; Boisnard, L.; Boit, L.; Bonneau,
   F.; Borzeix, S.; Briet, R.; Buey, J. -T.; Butler, B.; Cailleau, D.;
   Cautain, R.; Chabaud, P. -Y.; Chaintreuil, S.; Chiavassa, F.; Costes,
   V.; Cuna Parrho, V.; de Oliveira Fialho, F.; Decaudin, M.; Defise,
   J. -M.; Djalal, S.; Epstein, G.; Exil, G. -E.; Fauré, C.; Fenouillet,
   T.; Gaboriaud, A.; Gallic, A.; Gamet, P.; Gavalda, P.; Grolleau, E.;
   Gruneisen, R.; Gueguen, L.; Guis, V.; Guivarc'h, V.; Guterman, P.;
   Hallouard, D.; Hasiba, J.; Heuripeau, F.; Huntzinger, G.; Hustaix,
   H.; Imad, C.; Imbert, C.; Johlander, B.; Jouret, M.; Journoud, P.;
   Karioty, F.; Kerjean, L.; Lafaille, V.; Lafond, L.; Lam-Trong, T.;
   Landiech, P.; Lapeyrere, V.; Larqué, T.; Laudet, P.; Lautier, N.;
   Lecann, H.; Lefevre, L.; Leruyet, B.; Levacher, P.; Magnan, A.; Mazy,
   E.; Mertens, F.; Mesnager, J. -M.; Meunier, J. -C.; Michel, J. -P.;
   Monjoin, W.; Naudet, D.; Nguyen-Kim, K.; Orcesi, J. -L.; Ottacher,
   H.; Perez, R.; Peter, G.; Plasson, P.; Plesseria, J. -Y.; Pontet, B.;
   Pradines, A.; Quentin, C.; Reynaud, J. -L.; Rolland, G.; Rollenhagen,
   F.; Romagnan, R.; Russ, N.; Schmidt, R.; Schwartz, N.; Sebbag, I.;
   Sedes, G.; Smit, H.; Steller, M. B.; Sunter, W.; Surace, C.; Tello,
   M.; Tiphène, D.; Toulouse, P.; Ulmer, B.; Vandermarcq, O.; Vergnault,
   E.; Vuillemin, A.; Zanatta, P.
2009A&A...506..287L    Altcode: 2009arXiv0908.0241L
  Aims: We report the discovery of very shallow (Δ F/F ≈ 3.4×
  10<SUP>-4</SUP>), periodic dips in the light curve of an active V =
  11.7 G9V star observed by the CoRoT satellite, which we interpret as
  caused by a transiting companion. We describe the 3-colour CoRoT
  data and complementary ground-based observations that support
  the planetary nature of the companion. <BR />Methods: We used
  CoRoT colours information, good angular resolution ground-based
  photometric observations in- and out- of transit, adaptive optics
  imaging, near-infrared spectroscopy, and preliminary results from
  radial velocity measurements, to test the diluted eclipsing binary
  scenarios. The parameters of the host star were derived from optical
  spectra, which were then combined with the CoRoT light curve to derive
  parameters of the companion. <BR />Results: We examined all conceivable
  cases of false positives carefully, and all the tests support the
  planetary hypothesis. Blends with separation &gt;0.40´´or triple
  systems are almost excluded with a 8 × 10<SUP>-4</SUP> risk left. We
  conclude that, inasmuch we have been exhaustive, we have discovered
  a planetary companion, named CoRoT-7b, for which we derive a period
  of 0.853 59 ± 3 × 10<SUP>-5</SUP> day and a radius of R<SUB>p</SUB>
  = 1.68 ± 0.09 R_Earth. Analysis of preliminary radial velocity data
  yields an upper limit of 21 M_Earth for the companion mass, supporting
  the finding. <BR />Conclusions: CoRoT-7b is very likely the first
  Super-Earth with a measured radius. This object illustrates what will
  probably become a common situation with missions such as Kepler, namely
  the need to establish the planetary origin of transits in the absence of
  a firm radial velocity detection and mass measurement. The composition
  of CoRoT-7b remains loosely constrained without a precise mass. A very
  high surface temperature on its irradiated face, ≈1800-2600 K at the
  substellar point, and a very low one, ≈50 K, on its dark face assuming
  no atmosphere, have been derived. <P />The CoRoT space mission,
  launched on 27 December 2006, has been developed and is operated by
  CNES, with the contribution of Austria, Belgium, Brazil, ESA, Germany,
  and Spain. First CoRoT data are available to the public from the
  CoRoT archive: http://idoc-corot.ias.u-psud.fr. The complementary
  observations were obtained with MegaPrime/MegaCam, a joint project of
  CFHT and CEA/DAPNIA, at the Canada-France-Hawaii Telescope (CFHT) which
  is operated by NRC in Canada, INSU-CNRS in France, and the University of
  Hawaii; ESO Telescopes at the La Silla and Paranal Observatories under
  programme ID 081.C-0413(C), DDT 282.C-5015; the IAC80 telescope operated
  by the Instituto de Astrofísica de Tenerife at the Observatorio del
  Teide; the Isaac Newton Telescope (INT), operated on the island of
  La Palma by the Isaac Newton group in the Spanish Observatorio del
  Roque de Los Muchachos of the Instituto de Astrofisica de Canarias;
  and at the Anglo-Australian Telescope that have been funded by the
  Optical Infrared Coordination network (OPTICON), a major international
  collaboration supported by the Research Infrastructures Programme of
  the European Commissions Sixth Framework Programme; Radial-velocity
  observations were obtained with the SOPHIE spectrograph at the 1.93m
  telescope of Observatoire de Haute Provence, France.

---------------------------------------------------------
Title: A Doppler Spectro-Imager dedicated to Jovian seismology and
    aeronomy onboard on Laplace/EJSM Jupiter Ganymede Orbiter
Authors: Schmider, F. X.; Gaulme, P.; Appourchaux, T.; Guillot, T.;
   Mosser, B.; Rouesnel, F.; Sanchez-Lavega, A.; Tosi, F.; Mousis, O.;
   Eff-Darwich, A.
2009epsc.conf...82S    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Radius Determination of Solar-type Stars Using
Asteroseismology: What to Expect from the Kepler Mission
Authors: Stello, Dennis; Chaplin, William J.; Bruntt, Hans; Creevey,
   Orlagh L.; García-Hernández, Antonio; Monteiro, Mario J. P. F. G.;
   Moya, Andrés; Quirion, Pierre-Olivier; Sousa, Sergio G.; Suárez,
   Juan-Carlos; Appourchaux, Thierry; Arentoft, Torben; Ballot, Jerome;
   Bedding, Timothy R.; Christensen-Dalsgaard, Jørgen; Elsworth,
   Yvonne; Fletcher, Stephen T.; García, Rafael A.; Houdek, Günter;
   Jiménez-Reyes, Sebastian J.; Kjeldsen, Hans; New, Roger; Régulo,
   Clara; Salabert, David; Toutain, Thierry
2009ApJ...700.1589S    Altcode: 2009arXiv0906.0766S
  For distant stars, as observed by the NASA Kepler satellite,
  parallax information is currently of fairly low quality and is not
  complete. This limits the precision with which the absolute sizes of
  the stars and their potential transiting planets can be determined by
  traditional methods. Asteroseismology will be used to aid the radius
  determination of stars observed during NASA's Kepler mission. We
  report on the recent asteroFLAG hare-and-hounds Exercise#2, where
  a group of "hares" simulated data of F-K main-sequence stars that a
  group of "hounds" sought to analyze, aimed at determining the stellar
  radii. We investigated stars in the range 9 &lt; V &lt; 15, both
  with and without parallaxes. We further test different uncertainties
  in T <SUB>eff</SUB>, and compare results with and without using
  asteroseismic constraints. Based on the asteroseismic large frequency
  spacing, obtained from simulations of 4 yr time series data from
  the Kepler mission, we demonstrate that the stellar radii can be
  correctly and precisely determined, when combined with traditional
  stellar parameters from the Kepler Input Catalogue. The radii found
  by the various methods used by each independent hound generally agree
  with the true values of the artificial stars to within 3%, when the
  large frequency spacing is used. This is 5-10 times better than the
  results where seismology is not applied. These results give strong
  confidence that radius estimation can be performed to better than 3%
  for solar-like stars using automatic pipeline reduction. Even when the
  stellar distance and luminosity are unknown we can obtain the same level
  of agreement. Given the uncertainties used for this exercise we find
  that the input log g and parallax do not help to constrain the radius,
  and that T <SUB>eff</SUB> and metallicity are the only parameters we
  need in addition to the large frequency spacing. It is the uncertainty
  in the metallicity that dominates the uncertainty in the radius.

---------------------------------------------------------
Title: SIAMOIS: asteroseismology in Antarctica
Authors: Mosser, B.; Buey, T.; Catala, C.; Appourchaux, T.; Charpinet,
   S.; Mathias, Ph.; Maillard, J. P.; Siamois Team
2009CoAst.158..337M    Altcode:
  SIAMOIS is a ground-based asteroseismology project, to pursue velocity
  measurements from the Dome C Concordia station in Antarctica. The
  scientific program of SIAMOIS is based on the very precise asteroseismic
  observation of nearby bright targets, focussing on the observations of
  solar-like oscillations in solar-like stars. Spectrometric observations
  with SIAMOIS will be able to detect l=3 oscillation modes that cannot
  be analyzed with space-borne photometric observations. The Doppler
  data, less affected by the stellar activity noise, will yield a more
  precise mode structure inversion, thus a high-precision determination
  of the stellar interior structure. The benefit of precise Doppler
  observations of nearby targets, with addition of interferometric and
  high-resolution spectrometric measurements, will allow us to investigate
  in detail the physical laws governing the stellar interior structure and
  evolution. <P />Dome C appears to be the ideal place for ground-based
  asteroseismic observations as it is capable of delivering a duty
  cycle as high as 90% during the three-month long polar night. This
  duty cycle, a crucial point for asteroseismology, is comparable to
  space-borne observations. The SIAMOIS concept is based on Fourier
  Transform interferometry, which leads to a small instrument designed
  and developed for the harsh conditions in Antarctica. The instrument
  will be fully automatic, with no moving parts, and it will require
  only a very simple initial set up in Antarctica.

---------------------------------------------------------
Title: Solar-Like Oscillations in a Massive Star
Authors: Belkacem, Kévin; Samadi, Réza; Goupil, Marie-Jo; Lefèvre,
   Laure; Baudin, Fréderic; Deheuvels, Sébastien; Dupret, Marc-Antoine;
   Appourchaux, Thierry; Scuflaire, Richard; Auvergne, Michel; Catala,
   Claude; Michel, Eric; Miglio, Andrea; Montalban, Josefina; Thoul,
   Anne; Talon, Suzanne; Baglin, Annie; Noels, Arlette
2009Sci...324.1540B    Altcode: 2009arXiv0906.3788B
  Seismology of stars provides insight into the physical mechanisms
  taking place in their interior, with modes of oscillation probing
  different layers. Low-amplitude acoustic oscillations excited by
  turbulent convection were detected four decades ago in the Sun and
  more recently in low-mass main-sequence stars. Using data gathered
  by the Convection Rotation and Planetary Transits mission, we report
  here on the detection of solar-like oscillations in a massive star,
  V1449 Aql, which is a known large-amplitude (β Cephei) pulsator.

---------------------------------------------------------
Title: Measurement of Low Signal-To-Noise Ratio Solar p-Modes in
    Spatially Resolved Helioseismic Data
Authors: Salabert, D.; Leibacher, J.; Appourchaux, T.; Hill, F.
2009ApJ...696..653S    Altcode: 2009arXiv0902.2561S
  We present an adaptation of the rotation-corrected, m-averaged
  spectrum technique designed to observe low signal-to-noise ratio
  (S/N), low-frequency solar p-modes. The frequency shift of each
  of the 2l + 1 m spectra of a given (n, l) multiplet is chosen that
  maximizes the likelihood of the m-averaged spectrum. A high S/N can
  result from combining individual low S/N, individual-m spectra, none
  of which would yield a strong enough peak to measure. We apply the
  technique to Global Oscillation Network Group and Michelson Doppler
  Imager data and show that it allows us to measure modes with lower
  frequencies than those obtained with classic peak-fitting analysis
  of the individual-m spectra. We measure their central frequencies,
  splittings, asymmetries, lifetimes, and amplitudes. The low frequency,
  low- and intermediate-angular degrees rendered accessible by this
  new method correspond to modes that are sensitive to the deep solar
  interior down to the core (l &lt;= 3) and to the radiative interior
  (4 &lt;= l &lt;= 35). Moreover, the low-frequency modes have deeper
  upper turning points, and are thus less sensitive to the turbulence and
  magnetic fields of the outer layers, as well as uncertainties in the
  nature of the external boundary condition. As a result of their longer
  lifetimes (narrower linewidths) at the same S/N the determination of
  the frequencies of lower frequency modes is more accurate, and the
  resulting inversions should be more precise.

---------------------------------------------------------
Title: Intrinsic photometric characterisation of stellar oscillations
    and granulation. Solar reference values and CoRoT response functions
Authors: Michel, E.; Samadi, R.; Baudin, F.; Barban, C.; Appourchaux,
   T.; Auvergne, M.
2009A&A...495..979M    Altcode: 2008arXiv0809.1078M
  Context: Measuring amplitudes of solar-like oscillations and the
  granulation power spectral density constitute two promising sources
  of information to improve our understanding and description of the
  convection in outer layers of stars. However, different instruments,
  using different techniques and different bandpasses, give measurements
  that cannot be directly compared to each other or to theoretical
  values. <BR />Aims: In this work, we define simple response functions to
  derive intrinsic oscillation amplitudes and granulation power densities,
  from photometry measurements obtained with a specific instrument
  on a specific star. <BR />Methods: We test this method on different
  photometry data sets obtained on the Sun with two different instruments
  in three different bandpasses. <BR />Results: We show that the results
  are in good agreement and we establish reference intrinsic values for
  the Sun with photometry. We also compute the response functions of
  the CoRoT instrument for a range of parameters representative of the
  Main Sequence solar-like pulsators to be observed with CoRoT. We show
  that these response functions can be conveniently described by simple
  analytic functions of the effective temperature of the target star.

---------------------------------------------------------
Title: POLAR investigation of the Sun—POLARIS
Authors: Appourchaux, T.; Liewer, P.; Watt, M.; Alexander, D.;
   Andretta, V.; Auchère, F.; D'Arrigo, P.; Ayon, J.; Corbard, T.;
   Fineschi, S.; Finsterle, W.; Floyd, L.; Garbe, G.; Gizon, L.; Hassler,
   D.; Harra, L.; Kosovichev, A.; Leibacher, J.; Leipold, M.; Murphy,
   N.; Maksimovic, M.; Martinez-Pillet, V.; Matthews, B. S. A.; Mewaldt,
   R.; Moses, D.; Newmark, J.; Régnier, S.; Schmutz, W.; Socker, D.;
   Spadaro, D.; Stuttard, M.; Trosseille, C.; Ulrich, R.; Velli, M.;
   Vourlidas, A.; Wimmer-Schweingruber, C. R.; Zurbuchen, T.
2009ExA....23.1079A    Altcode: 2008ExA...tmp...40A; 2008arXiv0805.4389A
  The POLAR Investigation of the Sun (POLARIS) mission uses a combination
  of a gravity assist and solar sail propulsion to place a spacecraft
  in a 0.48 AU circular orbit around the Sun with an inclination of 75°
  with respect to solar equator. This challenging orbit is made possible
  by the challenging development of solar sail propulsion. This first
  extended view of the high-latitude regions of the Sun will enable
  crucial observations not possible from the ecliptic viewpoint or from
  Solar Orbiter. While Solar Orbiter would give the first glimpse of
  the high latitude magnetic field and flows to probe the solar dynamo,
  it does not have sufficient viewing of the polar regions to achieve
  POLARIS’s primary objective: determining the relation between the
  magnetism and dynamics of the Sun’s polar regions and the solar cycle.

---------------------------------------------------------
Title: Astrodynamical Space Test of Relativity Using Optical Devices
    I (ASTROD I)—A class-M fundamental physics mission proposal for
    Cosmic Vision 2015-2025
Authors: Appourchaux, Thierry; Burston, Raymond; Chen, Yanbei; Cruise,
   Michael; Dittus, Hansjörg; Foulon, Bernard; Gill, Patrick; Gizon,
   Laurent; Klein, Hugh; Klioner, Sergei; Kopeikin, Sergei; Krüger, Hans;
   Lämmerzahl, Claus; Lobo, Alberto; Luo, Xinlian; Margolis, Helen; Ni,
   Wei-Tou; Patón, Antonio Pulido; Peng, Qiuhe; Peters, Achim; Rasel,
   Ernst; Rüdiger, Albrecht; Samain, Étienne; Selig, Hanns; Shaul,
   Diana; Sumner, Timothy; Theil, Stephan; Touboul, Pierre; Turyshev,
   Slava; Wang, Haitao; Wang, Li; Wen, Linqing; Wicht, Andreas; Wu, Ji;
   Zhang, Xiaomin; Zhao, Cheng
2009ExA....23..491A    Altcode: 2008arXiv0802.0582A
  ASTROD I is a planned interplanetary space mission with multiple
  goals. The primary aims are: to test general relativity with
  an improvement in sensitivity of over three orders of magnitude,
  improving our understanding of gravity and aiding the development of
  a new quantum gravity theory; to measure key solar system parameters
  with increased accuracy, advancing solar physics and our knowledge
  of the solar system; and to measure the time rate of change of the
  gravitational constant with an order of magnitude improvement and
  the anomalous Pioneer acceleration, thereby probing dark matter and
  dark energy gravitationally. It is an international project, with
  major contributions from Europe and China and is envisaged as the
  first in a series of ASTROD missions. ASTROD I will consist of one
  spacecraft carrying a telescope, four lasers, two event timers and a
  clock. Two-way, two-wavelength laser pulse ranging will be used between
  the spacecraft in a solar orbit and deep space laser stations on Earth,
  to achieve the ASTROD I goals. A second mission, ASTROD (ASTROD II)
  is envisaged as a three-spacecraft mission which would test General
  Relativity to 1 ppb, enable detection of solar g-modes, measure the
  solar Lense-Thirring effect to 10 ppm, and probe gravitational waves
  at frequencies below the LISA bandwidth. In the third phase (ASTROD
  III or Super-ASTROD), larger orbits could be implemented to map the
  outer solar system and to probe primordial gravitational-waves at
  frequencies below the ASTROD II bandwidth.

---------------------------------------------------------
Title: First asteroseismic results from CoRoT
Authors: Michel, E.; Baglin, A.; Weiss, W. W.; Auvergne, M.; Catala,
   C.; Aerts, C.; Appourchaux, T.; Barban, C.; Baudin, F.; Briquet,
   M. -L.; Carrier, F.; Debosher, J.; De Ridder, J.; Garcia, R. A.;
   Garrido, R.; Gutierrez, J.; Kallinger, T.; Lefevre, L.; Neiner, C.;
   Poretti, E.; Samadi, R.; Sarro, L.; COROT Team
2008CoAst.157...69M    Altcode:
  About one year after the end of the first observational run and
  six months after the first CoRoT data delivery, we comment the data
  exploitation progress for different types of stars. We consider first
  results to illustrate how these data of unprecedented quality shed a
  new light on the field of stellar seismology.

---------------------------------------------------------
Title: Solar-like stars as seen by CoRoT
Authors: Garcia, R. A.; Appourchaux, T.; Baglin, A.; Auvergne, M.;
   Barban, C.; Baudin, F.; Michel, E.; Mosser, B.; Samadi, R.; Data
   Analysis Team D. A. T
2008CoAst.157..288G    Altcode:
  For more than a year, photometric high-quality data have been achieved
  from the CoRoT (COnvection ROtation and Planetary Transits; Baglin et
  al. 2006, Michel et al. 2008) min- isatellite developed by the French
  space agency (CNES) in collaboration with the Science Program of ESA,
  Austria, Belgium, Brazil Germany and Spain. The power spectrum of
  4 dif- ferent solar-like stars (stars having sub-surface convective
  zones showing an acoustic (p) mode spectrum) has been obtained with
  unprecedented quality allowing the precise study of their seismic
  properties. These solar-like stars are F stars with masses in the
  range 1.0 to 1.4 M⊙ and are significantly hotter than the Sun.

---------------------------------------------------------
Title: First asteroseismic results from CoRoT
Authors: Michel, E.; Baglin, A.; Weiss, W. W.; Auvergne, M.; Catala,
   C.; Aerts, C.; Appourchaux, T.; Barban, C.; Baudin, F.; Briquet, M.;
   Carrier, F.; Degroote, P.; De Ridder, J.; Garcia, R. A.; Garrido,
   R.; Gutiérrez-Soto, J.; Kallinger, T.; Lefevre, L.; Neiner,
   C.; Poretti, E.; Samadi, R.; Sarro, L.; Alecian, G.; Andrade, L.;
   Ballot, J.; Benomar, O.; Berthomieu, G.; Boumier, P.; Charpinet, S.;
   de Batz, B.; Deheuvels, S.; Dupret, M. -A.; Emilio, M.; Fabregat,
   J.; Facanha, W.; Floquet, M.; Frémat, Y.; Fridlund, M.; Goupil,
   M. -J.; Grotsch-Noels, A.; Handler, G.; Huat, A. -L.; Hubert, A. -M.;
   Janot-Pacheco, E.; Kjeldsen, H.; Lebreton, Y.; Leroy, B.; Martayan,
   C.; Mathias, P.; Miglio, A.; Montalban, J.; Monteiro, M. J. P. F. G.;
   Mosser, B.; Provost, J; Regulo, C.; Renan de Medeiros, J.; Ribas,
   I.; Roca Cortés, T.; Roxburgh, I.; Suso, J.; Thoul, A.; Toutain, T.;
   Tiphene, D.; Turck-Chieze, S.; Vauclair, S.; Vauclair, G.; Zwintz, K.
2008CoAst.156...73M    Altcode:
  About one year after the end of the first observational run and
  six months after the first CoRoT data delivery, we comment the data
  exploitation progress for different types of stars. We consider first
  results to illustrate how these data of unprecedented quality shed a
  new light on the field of stellar seismology.

---------------------------------------------------------
Title: A Multisite Campaign to Measure Solar-like Oscillations in
    Procyon. I. Observations, Data Reduction, and Slow Variations
Authors: Arentoft, Torben; Kjeldsen, Hans; Bedding, Timothy R.;
   Bazot, Michaël; Christensen-Dalsgaard, Jørgen; Dall, Thomas H.;
   Karoff, Christoffer; Carrier, Fabien; Eggenberger, Patrick; Sosnowska,
   Danuta; Wittenmyer, Robert A.; Endl, Michael; Metcalfe, Travis S.;
   Hekker, Saskia; Reffert, Sabine; Butler, R. Paul; Bruntt, Hans;
   Kiss, László L.; O'Toole, Simon J.; Kambe, Eiji; Ando, Hiroyasu;
   Izumiura, Hideyuki; Sato, Bun'ei; Hartmann, Michael; Hatzes, Artie;
   Bouchy, Francois; Mosser, Benoit; Appourchaux, Thierry; Barban,
   Caroline; Berthomieu, Gabrielle; Garcia, Rafael A.; Michel, Eric;
   Provost, Janine; Turck-Chièze, Sylvaine; Martić, Milena; Lebrun,
   Jean-Claude; Schmitt, Jerome; Bertaux, Jean-Loup; Bonanno, Alfio;
   Benatti, Serena; Claudi, Riccardo U.; Cosentino, Rosario; Leccia,
   Silvio; Frandsen, Søren; Brogaard, Karsten; Glowienka, Lars; Grundahl,
   Frank; Stempels, Eric
2008ApJ...687.1180A    Altcode: 2008arXiv0807.3794A
  We have carried out a multisite campaign to measure oscillations in
  the F5 star Procyon A. We obtained high-precision velocity observations
  over more than three weeks with 11 telescopes, with almost continuous
  coverage for the central 10 days. This represents the most extensive
  campaign so far organized on any solar-type oscillator. We describe in
  detail the methods we used for processing and combining the data. These
  involved calculating weights for the velocity time series from the
  measurement uncertainties and adjusting them in order to minimize the
  noise level of the combined data. The time series of velocities for
  Procyon shows the clear signature of oscillations, with a plateau of
  excess power that is centered at 0.9 mHz and is broader than has been
  seen for other stars. The mean amplitude of the radial modes is 38.1
  +/- 1.3 cm s<SUP>-1</SUP> (2.0 times solar), which is consistent with
  previous detections from the ground and by the WIRE spacecraft, and
  also with the upper limit set by the MOST spacecraft. The variation
  of the amplitude during the observing campaign allows us to estimate
  the mode lifetime to be 1.5<SUP>+ 1.9</SUP><SUB>-0.8</SUB> days. We
  also find a slow variation in the radial velocity of Procyon, with good
  agreement between different telescopes. These variations are remarkably
  similar to those seen in the Sun, and we interpret them as being due to
  rotational modulation from active regions on the stellar surface. The
  variations appear to have a period of about 10 days, which presumably
  equals the stellar rotation period or, perhaps, half of it. The amount
  of power in these slow variations indicates that the fractional area of
  Procyon covered by active regions is slightly higher than for the Sun.

---------------------------------------------------------
Title: SIAMOIS: Seismic Interferometer to Measure Oscillations in
    the Interior of Stars
Authors: Mosser, Benoit; Appourchaux, Thierry; Catala, Claude; Buey,
   Jean-Tristan; SIAMOIS Team
2008JPhCS.118a2042M    Altcode:
  SIAMOIS is a project devoted to ground-based asteroseismology,
  involving an instrument to be installed at the Dome C Concordia station
  in Antarctica. SIAMOIS provides an asteroseismic programme that can
  follow the way currently opened by the space project CoRoT, with unique
  information on G and K type bright stars on the main sequence. In
  addition, spectrometric observations with SIAMOIS will be able to
  detect oscillation modes that cannot be analyzed in photometry:
  the Doppler data, less affected by the stellar activity noise,
  yield a more precise mode structure inversion. The SIAMOIS concept
  is based on Fourier Transform interferometry. Such a principle leads
  to a small instrument designed and developed for the harsh conditions
  in Antarctic. The instrument will be fully automatic, with no moving
  parts, and a very simple initial set up in Antarctic. The dedicated
  scientific programme will avoid the complications related to a
  versatile instrument. Data reduction will be performed in real time,
  and the transfer of the asteroseismic data to Europe will require
  only a modest bandwidth. SIAMOIS will observe with a dedicated small
  40-cm telescope. Dome C appears to be the ideal place for ground-based
  asteroseismic observations. The unequalled weather conditions yield a
  duty cycle as high as 90% over 3 months, as was observed during the 2005
  wintering. This high duty cycle, a crucial point for asteroseismology,
  is comparable to the best space-based observations. Long time series
  (up to 3 months) will be possible, thanks to the long duration of the
  polar night. SIAMOIS can be seen as one of the very first observational
  projects in astronomy at Dome C. Its scientific programme will take
  full advantage of the unique quality of this site, and will constitute a
  necessary first step in preparation of future more ambitious programmes
  requiring more sophisticated instrumentation and larger collectors.

---------------------------------------------------------
Title: Oscillations in Procyon A: First results from a multi-site
    campaign
Authors: Hekker, S.; Arentoft, T.; Kjeldsen, H.; Bedding, T. R.;
   Christensen-Dalsgaard, J.; Reffert, S.; Bruntt, H.; Butler, R. P.;
   Kiss, L. L.; O'Toole, S. J.; Kambe, E.; Ando, H.; Izumiura, H.;
   Sato, B.; Hartmann, M.; Hatzes, A. P.; Appourchaux, T.; Barban, C.;
   Berthomieu, G.; Bouchy, F.; García, R. A.; Lebrun, J. -C.; Martić,
   M.; Michel, E.; Mosser, B.; Nghiem, P. A. P.; Provost, J.; Samadi,
   R.; Thévenin, F.; Turck-Chièze, S.; Bonanno, S. A.; Benatti, S.;
   Claudi, R. U.; Cosentino, R.; Leccia, S.; Frandsen, S.; Brogaard,
   K.; Grundahl, F.; Stempels, H. C.; Bazot, M.; Dall, T. H.; Karoff,
   C.; Carrier, F.; Eggenberger, P.; Sosnowska, D.; Wittenmyer, R. A.;
   Endl, M.; Metcalfe, T. S.
2008JPhCS.118a2059H    Altcode: 2007arXiv0710.3772H
  Procyon A is a bright F5IV star in a binary system. Although the
  distance, mass and angular diameter of this star are all known with high
  precision, the exact evolutionary state is still unclear. Evolutionary
  tracks with different ages and different mass fractions of hydrogen
  in the core pass, within the errors, through the observed position of
  Procyon A in the Hertzsprung-Russell diagram. For more than15 years
  several different groups have studied the solar-like oscillations in
  Procyon A to determine its evolutionary state. Although several studies
  independently detected power excess in the periodogram, there is no
  agreement on the actual oscillation frequencies yet. This is probably
  due to either insufficient high-quality data (i.e., aliasing) or due
  to intrinsic properties of the star (i.e., short mode lifetimes). Now
  a spectroscopic multi-site campaign using 10 telescopes world-wide
  (minimizing aliasing effects) with a total time span of nearly 4
  weeks (increase the frequency resolution) is performed to identify
  frequencies in this star and finally determine its properties and
  evolutionary state.

---------------------------------------------------------
Title: Detecting solar g modes with ASTROD
Authors: Burston, R.; Gizon, L.; Appourchaux, T.; Ni, W. -T.; ASTROD
   I ESA cosmic vision 2015-2025 Team
2008JPhCS.118a2043B    Altcode: 2008arXiv0802.1614B
  We present an up-to-date estimate for the prospect of using the
  Astrodynamical Space Test of Relativity using Optical Devices (ASTROD)
  [1, 2, 3, 4] for an unambiguous detection of solar g modes (f &lt; 400
  μHz) through their gravitational signature. There are currently two
  major efforts to detect low-frequency gravitational effects, ASTROD and
  the Laser Interferometer Space Antenna (LISA) [5]. Using the most recent
  g mode surface amplitude estimates, both observational and theoretical,
  it is unclear whether LISA will be capable of successfully detecting
  these modes. The ASTROD project may be better suited for detection as
  its sensitivity curve is shifted towards lower frequencies with the
  best sensitivity occurring in the range 100 - 300 μHz.

---------------------------------------------------------
Title: CoRoT Measures Solar-Like Oscillations and Granulation in
    Stars Hotter Than the Sun
Authors: Michel, Eric; Baglin, Annie; Auvergne, Michel; Catala,
   Claude; Samadi, Reza; Baudin, Frédéric; Appourchaux, Thierry; Barban,
   Caroline; Weiss, Werner W.; Berthomieu, Gabrielle; Boumier, Patrick;
   Dupret, Marc-Antoine; Garcia, Rafael A.; Fridlund, Malcolm; Garrido,
   Rafael; Goupil, Marie-Jo; Kjeldsen, Hans; Lebreton, Yveline; Mosser,
   Benoît; Grotsch-Noels, Arlette; Janot-Pacheco, Eduardo; Provost,
   Janine; Roxburgh, Ian W.; Thoul, Anne; Toutain, Thierry; Tiphène,
   Didier; Turck-Chieze, Sylvaine; Vauclair, Sylvie D.; Vauclair,
   Gérard P.; Aerts, Conny; Alecian, Georges; Ballot, Jérôme;
   Charpinet, Stéphane; Hubert, Anne-Marie; Lignières, François;
   Mathias, Philippe; Monteiro, Mario J. P. F. G.; Neiner, Coralie;
   Poretti, Ennio; Renan de Medeiros, José; Ribas, Ignasi; Rieutord,
   Michel L.; Roca Cortés, Teodoro; Zwintz, Konstanze
2008Sci...322..558M    Altcode: 2008arXiv0812.1267M
  Oscillations of the Sun have been used to understand its interior
  structure. The extension of similar studies to more distant stars
  has raised many difficulties despite the strong efforts of the
  international community over the past decades. The CoRoT (Convection
  Rotation and Planetary Transits) satellite, launched in December 2006,
  has now measured oscillations and the stellar granulation signature
  in three main sequence stars that are noticeably hotter than the
  sun. The oscillation amplitudes are about 1.5 times as large as
  those in the Sun; the stellar granulation is up to three times as
  high. The stellar amplitudes are about 25% below the theoretic values,
  providing a measurement of the nonadiabaticity of the process ruling
  the oscillations in the outer layers of the stars.

---------------------------------------------------------
Title: solarFLAG hare and hounds: estimation of p-mode frequencies
    from Sun-as-star helioseismology data
Authors: Jiménez-Reyes, S. J.; Chaplin, W. J.; García, R. A.;
   Appourchaux, T.; Baudin, F.; Boumier, P.; Elsworth, Y.; Fletcher,
   S. T.; Lazrek, M.; Leibacher, J. W.; Lochard, J.; New, R.; Régulo,
   C.; Salabert, D.; Toutain, T.; Verner, G. A.; Wachter, R.
2008MNRAS.389.1780J    Altcode: 2008arXiv0807.0989J; 2008MNRAS.tmp..954J; 2008MNRAS.tmp.1026J
  We report on the results of the latest solarFLAG hare-and-hounds
  exercise, which was concerned with testing methods for extraction
  of frequencies of low-degree solar p modes from data collected
  by Sun-as-a-star observations. We have used the new solarFLAG
  simulator, which includes the effects of correlated mode excitation and
  correlations with background noise, to make artificial time-series data
  that mimic Doppler velocity observations of the Sun-as-a-star. The
  correlations give rise to asymmetry of mode peaks in the frequency
  power spectrum. 10 members of the group (the hounds) applied their
  `peak-bagging' codes to a 3456-d data set, and the estimated
  mode frequencies were returned to the hare (who was WJC) for
  comparison. Analysis of the results reveals a systematic bias in the
  estimated frequencies of modes above ~1.8mHz. The bias is negative,
  meaning the estimated frequencies systematically underestimate the
  input frequencies. <P />We identify two sources that are the dominant
  contributions to the frequency bias. Both sources involve failure to
  model accurately subtle aspects of the observed power spectral density
  in the part (window) of the frequency power spectrum that is being
  fitted. One source of bias arises from a failure to account for the
  power spectral density coming from all those modes whose frequencies lie
  outside the fitting windows. The other source arises from a failure to
  account for the power spectral density of the weak l = 4 and 5 modes,
  which are often ignored in Sun-as-a-star analysis. The Sun-as-a-star
  peak-bagging codes need to allow for both sources, otherwise the
  frequencies are likely to be biased.

---------------------------------------------------------
Title: AsteroFLAG — from the Sun to the stars
Authors: Chaplin, W. J.; Appourchaux, T.; Arentoft, T.; Ballot, J.;
   Baudin, F.; Bazot, M.; Bedding, T. R.; Christensen-Dalsgaard, J.;
   Creevey, O. L.; Duez, V.; Elsworth, Y.; Fletcher, S. T.; García,
   R. A.; Gough, D. O.; Jiménez, A.; Jiménez-Reyes, S. J.; Houdek, G.;
   Kjeldsen, H.; Lazrek, M.; Leibacher, J. W.; Monteiro, M. J. P. F. G.;
   Neiner, C.; New, R.; Régulo, C.; Salabert, D.; Samadi, R.; Sekii,
   T.; Sousa, S. G.; Toutain, T.; Turck-Chièze, S.
2008JPhCS.118a2048C    Altcode:
  We stand on the threshold of a critical expansion of asteroseismology
  of Sun-like stars, the study of stellar interiors by observation
  and analysis of their global acoustic modes of oscillation. The
  Sun-like oscillations give a very rich spectrum allowing the internal
  structure and dynamics to be probed down into the stellar cores to
  very high precision. Asteroseismic observations of many stars will
  allow multiple-point tests of crucial aspects of stellar evolution
  and dynamo theory. The aims of the asteroFLAG collaboration are to
  help the community to refine existing, and to develop new, methods
  for analysis of the asteroseismic data on the Sun-like oscillators.

---------------------------------------------------------
Title: Development of a new analysis technique to measure low
    radial-order p modes in spatially-resolved helioseismic data
Authors: Salabert, David; Leibacher, John W.; Appourchaux, Thierry
2008JPhCS.118a2086S    Altcode: 2007arXiv0711.2825S
  In order to take full advantage of the long time series collected by
  the GONG and MDI helioseismic projects, we present here an adaptation
  of the rotation-corrected m-averaged spectrum technique in order to
  observe low radial-order solar p modes. Modeled profiles of the solar
  rotation demonstrated the potential advantage of such a technique
  [1, 2, 3]. Here we develop a new analysis procedure which finds the
  best estimates of the shift of each m of a given (n, ι) multiplet,
  commonly expressed as an expansion in a set of orthogonal polynomials,
  which yield the narrowest mode in the m-averaged spectrum. We apply the
  technique to the GONG data for modes with 1 &lt;= ι &lt;= 25 and show
  that it allows us to measure lower-frequency modes than with classic
  peak-fitting analysis of the individual-m spectra.

---------------------------------------------------------
Title: CoRoT sounds the stars: p-mode parameters of Sun-like
    oscillations on HD 49933
Authors: Appourchaux, T.; Michel, E.; Auvergne, M.; Baglin, A.;
   Toutain, T.; Baudin, F.; Benomar, O.; Chaplin, W. J.; Deheuvels, S.;
   Samadi, R.; Verner, G. A.; Boumier, P.; García, R. A.; Mosser, B.;
   Hulot, J. -C.; Ballot, J.; Barban, C.; Elsworth, Y.; Jiménez-Reyes,
   S. J.; Kjeldsen, H.; Régulo, C.; Roxburgh, I. W.
2008A&A...488..705A    Altcode:
  Context: The first asteroseismology results from CoRoT are presented,
  on a star showing Sun-like oscillations. We have analyzed a 60 day
  lightcurve of high-quality photometric data collected by CoRoT on the
  F5 V star HD 49933. The data reveal a rich spectrum of overtones of
  low-degree p modes. <BR />Aims: Our aim was to extract robust estimates
  of the key parameters of the p modes observed in the power spectrum of
  the lightcurve. <BR />Methods: Estimation of the mode parameters was
  performed using maximum likelihood estimation of the power spectrum. A
  global fitting strategy was adopted whereby 15 mode orders of the
  mode spectrum (45 modes) were fitted simultaneously. <BR />Results:
  The parameter estimates that we list include mode frequencies,
  peak linewidths, mode amplitudes, and a mean rotational frequency
  splitting. We find that the average large frequency (overtone) spacing
  derived from the fitted mode frequencies is 85.9 ± 0.15 μHz. The
  frequency of maximum amplitude of the radial modes is at 1760 μHz,
  where the observed rms mode amplitude is 3.75 ± 0.23 ppm. The mean
  rotational splitting of the non-radial modes appears to be in the
  range ≈2.7 μHz to ≈3.4 μHz. The angle of inclination offered by
  the star, as determined by fits to the amplitude ratios of the modes,
  appears to be in the range ≈50 degrees to ≈62 degrees. <P />The
  CoRoT space mission, launched on <P />2006 December 27, was developed
  and is operated by the CNES, with <P />participation of the Science
  Programs of ESA, ESA's RSSD, Austria, <P />Belgium, Brazil, Germany
  and Spain.

---------------------------------------------------------
Title: On deriving p-mode parameters for inclined solar-like stars
Authors: Ballot, J.; Appourchaux, T.; Toutain, T.; Guittet, M.
2008A&A...486..867B    Altcode: 2008arXiv0803.0885B
  Context: Thanks to their high quality, new and upcoming asteroseismic
  observations, with CoRoT, Kepler, and from the ground, benefit from
  experience gained with helioseismology. <BR />Aims: We focus, in
  this paper, on solar-like oscillations, for which the inclination of
  the rotation axis is unknown. We present a theoretical study of the
  errors of p-mode parameters determined by means of a maximum-likelihood
  estimator, and we also analyze correlations and biases. <BR />Methods:
  We used different, complementary approaches: we performed either
  semi-analytical computation of the Hessian matrix, fitting of single
  mean profiles, or Monte Carlo simulations. <BR />Results: First, we
  give analytical approximations for the errors of frequency, inclination
  and rotational splitting. The determination of the inclination is
  very challenging for the common case of slow rotators (like the
  Sun), making the determination of a reliable rotational splitting
  difficult. Moreover, due to the numerous correlations, biases - more
  or less significant - can appear in the determination of various
  parameters in the case of bad inclination fittings, especially when
  a locking at 90° occurs. We also discuss this issue. Nevertheless,
  the central frequency and some derived parameters, such as the total
  power of the mode, are free of such biases.

---------------------------------------------------------
Title: Challenges for asteroseismic analysis of Sun-like stars
Authors: Chaplin, W. J.; Houdek, G.; Appourchaux, T.; Elsworth, Y.;
   New, R.; Toutain, T.
2008A&A...485..813C    Altcode: 2008arXiv0804.4371C
  Context: Asteroseismology of Sun-like stars is undergoing rapid
  expansion with, for example, new data from the CoRoT mission and
  continuation of ground-based campaigns. There is also the exciting
  upcoming prospect of NASA's Kepler mission, which will allow the
  asteroseismic study of several hundred Sun-like targets, in some cases
  for periods lasting up to a few years. <BR />Aims: The seismic mode
  parameters are the input data needed for making inference on stars
  and their internal structures. In this paper we discuss the ease with
  which it will be possible to extract estimates of individual mode
  parameters, dependent on the mass, age, and visual brightness of the
  star. Our results are generally applicable; however, we look at mode
  detectability in the context of the upcoming Kepler observations. <BR
  />Methods: To inform our discussions we make predictions of various
  seismic parameters. To do this we use simple empirical scaling relations
  and detailed pulsation computations of the stochastic excitation and
  damping characteristics of the Sun-like p modes. <BR />Results: The
  issues related to parameter extraction on individual p modes discussed
  here are mode detectability, the detectability and impact of stellar
  activity cycles, and the ability to measure properties of rotationally
  split components, which is dependent on the relative importance of
  the rotational characteristics of the star and the damping of the
  stochastically excited p modes.

---------------------------------------------------------
Title: Design of a Fabry-Perot interferometer for the SO/PHI
    instrument on Solar Orbiter
Authors: Trosseille, Clément; Appourchaux, Thierry; Fourmond,
   Jean-Jacques
2008SPIE.7010E..17T    Altcode: 2008SPIE.7010E..37T
  We present our work on the spectral analyser of the Polarimetric
  and Helioseismic Imager (PHI) instrument to be flown aboard ESA's
  Solar Orbiter mission. We detail the choices that were made to
  determine the concept of the spectral analyser, a Lithium Niobate
  Fabry-Perot interferometer, and its characteristics, as to fulfil both
  scientific needs and technical requirements. We will present the first
  experimental results - including stability, repeatability, parallelism,
  spectral homogeneity and imaging capability - on an air-spaced
  piezoelectric-tunable etalon, which is the backup solution for PHI.

---------------------------------------------------------
Title: Effect of the stellar inclination angle upon theoretical
    errors of l=1 p-mode parameters
Authors: Ballot, J.; Appourchaux, T.; Toutain, T.
2008AN....329..558B    Altcode:
  The asteroseismic observations provided by current and future
  missions like CoRoT or Kepler will have a quality closer to those
  obtained for the Sun. In this context, tools and methods developed
  for helioseismology can be applied to other stars. In this paper,
  we focus on solar-like oscillations of stars with an unknown rotation
  axis inclination and study, by means of maximum-likelihood estimation,
  the errors on the determination of l=1 p-mode parameters.

---------------------------------------------------------
Title: AsteroFLAG: First results from hare-and-hounds Exercise #1
Authors: Chaplin, W. J.; Appourchaux, T.; Arentoft, T.; Ballot, J.;
   Christensen-Dalsgaard, J.; Creevey, O. L.; Elsworth, Y.; Fletcher,
   S. T.; García, R. A.; Houdek, G.; Jiménez-Reyes, S. J.; Kjeldsen,
   H.; New, R.; Régulo, C.; Salabert, D.; Sekii, T.; Sousa, S. G.;
   Toutain, T.; rest of asteroFLAG Group
2008AN....329..549C    Altcode: 2008arXiv0803.4143C
  We report on initial results from the first phase of Exercise #1 of the
  asteroFLAG hare and hounds. The asteroFLAG group is helping to prepare
  for the asteroseismology component of NASA's Kepler mission, and the
  first phase of Exercise #1 is concerned with testing extraction of
  estimates of the large and small frequency spacings of the low-degree p
  modes from Kepler-like artificial data. These seismic frequency spacings
  will provide key input for complementing the exoplanet search data.

---------------------------------------------------------
Title: Helioseismology program for the PICARD satellite
Authors: Corbard, T.; Boumier, P.; Appourchaux, T.; Jiménez-Reyes,
   S. J.; Gelly, B.; PICARD Team
2008AN....329..508C    Altcode:
  The PICARD mission is a CNES micro-satellite to be launched in 2009. Its
  goal is to better understand the Sun and the potential impact of
  its activity on earth climate by measuring simultaneously the solar
  total and spectral irradiance, diameter, shape and oscillations. We
  present the scientific objectives, instrumental requirements and
  data products of the helioseismology program of PICARD which aims
  to observe the low to medium l p-mode oscillations in intensity
  and search for g-mode oscillation signatures at the limb. <P
  />http://www.picard-mission.cnes.fr

---------------------------------------------------------
Title: Bayesian approach for g-mode detection, or how to restrict
    our imagination
Authors: Appourchaux, T.
2008AN....329..485A    Altcode: 2007arXiv0711.0435A
  Nowadays, g-mode detection is based upon a priori theoretical
  knowledge. By doing so, detection becomes more restricted to what we can
  imagine. De facto, the universe of possibilities is made narrower. Such
  an approach is pertinent for Bayesian statisticians. Examples of
  how Bayesian inferences can be applied to spectral analysis and
  helioseismic power spectra are given. Our intention is not to give
  the full statistical framework (much too ambitious) but to provide
  an appetizer for going further in the direction of a proper Bayesian
  inference, especially for detecting gravity modes.

---------------------------------------------------------
Title: Low-Frequency Solar p Modes in GONG and MDI Observations
    using m-Averaged Spectra
Authors: Leibacher, J.; Salabert, D.; Appourchaux, T.; Hill, F.
2008AGUSMSP41A..06L    Altcode:
  The GONG and MDI global helioseismology pipelines provide solar acoustic
  mode parameters for 108- and 72-day time series respectively by fitting
  the 2 ℓ + 1 individual-m spectra of a given (n, ℓ/) multiplet
  either individually (GONG) or simultaneously (MDI). Our knowledge of
  the variable solar interior through helioseismic observations derives
  primarily from these two analysis pipelines. We have developed a
  new method to extract the mode parameters by adjusting the rotation-
  and structure-induced frequency shift for each m-spectrum to minimize
  the mode width in the m-averaged spectrum. The m-averaged spectrum
  appears to be a powerful tool for low signal-to-noise-ratio modes in the
  low-frequency range where the modes have very long lifetimes. Indeed,
  in the case of spatially-resolved helioseismic data (MDI, GONG, HMI),
  for a given multiplet (n, ℓ/), there exist 2 ℓ + 1 individual-m
  spectra, which can result in an average spectrum with a SNR ≫ 1 even
  when the individual-m spectra have a SNR &lt; 1. We show here that
  the m-averaged spectrum technique, applied to the GONG 108-day and MDI
  72-day time series, gives us access to a whole new range of predicted,
  low-SNR modes that had not been successfully fitted by the current
  MDI and GONG peak-fitting pipelines. We show that the modes that are
  measured by both techniques are extracted without bias. We apply this
  technique to 360-, 720-, 1080-, and 1440-day long GONG time series to
  infer the variability of the mode parameters with solar activity in
  the low-frequency range below ~ 1500 μHz.

---------------------------------------------------------
Title: Searching for p-modes in MOST Procyon data: another view
Authors: Baudin, F.; Appourchaux, T.; Boumier, P.; Kuschnig, R.;
   Leibacher, J. W.; Matthews, J. M.
2008A&A...478..461B    Altcode: 2007arXiv0711.0601B
  Context: Photometry of Procyon obtained by the MOST satellite in
  2004 has been searched for p modes by several groups, with sometimes
  contradictory interpretations. <BR />Aims: We explore two possible
  factors that complicate the analysis and may lead to erroneous reports
  of p modes in these data. <BR />Methods: Two methods are used to
  illustrate the role of subtle instrumental effects in the photometry:
  time-frequency analysis, and a search for regularly spaced peaks in a
  Fourier spectrum based on the echelle diagramme approach. <BR />Results:
  We find no convincing evidence of a p-mode signal in the MOST Procyon
  data. We can account for an apparent excess of power close to the p-mode
  frequency range and signs of structure in an echelle diagramme in terms
  of instrumental effects. <P />Based on data from the MOST satellite,
  a Canadian Space Agency mission, jointly operated by Dynacon Inc., the
  University of Toronto Institute for Aerospace Studies and the University
  of British Columbia, with the assistance of the University of Vienna.

---------------------------------------------------------
Title: Asteroseismology of Procyon with SOPHIE
Authors: Mosser, B.; Bouchy, F.; Martić, M.; Appourchaux, T.; Barban,
   C.; Berthomieu, G.; Garcia, R. A.; Lebrun, J. C.; Michel, E.; Provost,
   J.; Thévenin, F.; Turck-Chièze, S.
2008A&A...478..197M    Altcode: 2007arXiv0712.1368M
  Context: This paper reports a 9-night asteroseismic observation
  program conducted in January 2007 with the new spectrometer sophie
  at the OHP 193-cm telescope, on the F5 IV-V target Procyon A. <BR
  />Aims: This first asteroseismic program with sophie was intended
  to test the performance of the instrument with a bright but demanding
  asteroseismic target and was part of a multisite network. <BR />Methods:
  The sophie spectra have been reduced with the data reduction software
  provided by OHP. The Procyon asteroseismic data were then analyzed
  with statistical tools. The asymptotic analysis has been conducted
  considering possible curvature in the échelle diagram analysis. <BR
  />Results: These observations have proven the efficient performance of
  sophie used as an asteroseismometer, and succeed in a clear detection
  of the large spacing. An échelle diagram based on the 54-μHz
  spacing shows clear ridges. Identification of the peaks exhibits
  large spacings varying from about 52 μHz to 56 μHz. Outside
  the frequency range [0.9, 1.0 mHz] where the identification is
  confused, the large spacing increases at a rate of about dΔν/dn
  ≃ 0.2 μHz. This may explain some of the different values of
  the large spacing obtained by previous observations. <P />Based on
  observations collected with the sophie échelle spectrometer mounted
  on the 1.93-m telescope at OHP, France (program 06B.PNPS.BOU);
  http://www.obs-hp.fr/www/guide/ sophie/sophie-eng.html Table of
  radial velocity measurements is only available in electronic form
  at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5)
  or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/478/197

---------------------------------------------------------
Title: VizieR Online Data Catalog: Procyon (alpha CMi) radial
    velocities (Mosser+, 2008)
Authors: Mosser, B.; Bouchy, F.; Martic, M.; Appourchaux, T.; Barban,
   C.; Berthomieu, G.; Garcia, R. A.; Lebrun, J. C.; Michel, E.; Provost,
   J.; Thevenin, F.; Turck-Chieze, S.
2007yCat..34780197M    Altcode:
  Time series of the radial velocities of Procyon recorder with the
  echelle spectrometer SOPHIE at Observatoire de Haute Provence in
  January 2007. <P />(1 data file).

---------------------------------------------------------
Title: Simu-LC : a Light-Curve simulator for CoRoT
Authors: Baudin, F.; Samadi, R.; Appourchaux, T.; Michel, E.
2007arXiv0710.3378B    Altcode:
  Simulating the data that a space instrument like COROT will provide
  might look presomptuous. Indeed, it is certainly, when comparing to
  previous comparable instruments like IPHIR or GOLF. These two examples
  show that the nominal behaviour of the instrument is not always
  reached, but this does not prevent this instrument to provide very
  interesting data. However, despite some technical problems, IPHIR and
  GOLF yielded a wealth of scientific results. Thus, what is the interest
  of simulating COROT data? How close to reality these simualtions will
  get? This might not be the most important fact as the preparation of
  these simulations will help us to prepare the analysis of real data and
  to be ready in case of unexpected technical behaviour of the instrument
  perturbating the data, or unexpected physical behaviour of the targets
  of the instrument. A consequence of that is that the simulation tool
  must include technical and physical aspects, making the task even more
  difficult. These aspects cover: photon noise, p modes excitation,
  granulation signal, stellar activity signal, orbital perturbations,
  stellar rotation... The software presented here is freely available at:
  http://www.lesia.obspm.fr/~corotswg/simulightcurve.html

---------------------------------------------------------
Title: Needles in haystacks: how to use contemporaneous data in the
    search for low-frequency modes of oscillation of the Sun
Authors: Broomhall, A. M.; Chaplin, W. J.; Elsworth, Y.; Appourchaux,
   T.
2007MNRAS.379....2B    Altcode: 2007MNRAS.tmp..525B
  We show how to take advantage of contemporaneous data from two different
  instruments in the search for low-frequency modes of oscillation of
  the Sun. Contemporaneous data allow searches to be made for prominent,
  sharp concentrations of power which are coincident in frequency. Crucial
  to determining objective measures of the joint probability of the
  random occurrence of such features, which are potential candidates
  for modes, is a good understanding of the characteristics of the
  background noise. In this paper we show how to make proper allowance,
  in the calculation of the probability, for noise that is common to data
  from different instruments. This common noise is solar in origin, and
  comes from the solar granulation. Its presence makes calculation of the
  probability a non-trivial problem. We demonstrate application of the
  technique in searches for low-frequency p modes. The data we searched
  comprised 3071 d of contemporaneous Sun-as-a-star Doppler velocity
  observations made by the ground-based Birmingham Solar-Oscillations
  Network (BiSON), and the GOLF instrument onboard the ESA/NASA SOHO
  spacecraft.

---------------------------------------------------------
Title: On understanding the meaning of l = 2 and 3 p-mode frequencies
    as measured by various helioseismic instruments
Authors: Appourchaux, T.; Chaplin, W. J.
2007A&A...469.1151A    Altcode:
  Aims:Frequencies of the low-degree p-mode oscillations of the Sun
  may be extracted either from data collected by instruments that make
  full-disc observations of the Sun as a star, or from data collected
  by instruments that resolve, or image, the Sun's surface onto many
  detector elements. The two methods can show marked differences in
  their sensitivity to modes having certain combinations of degree and
  azimuthal order. These different sensitivities lead to differences
  in measurements of the central frequencies of the modes, which must
  be properly accounted for if data from two different instruments
  are to be compared, or combined. <BR />Methods: We perform an
  analytical derivation of the p-mode frequency offsets expected between
  contemporaneous Sun-as-a-star and resolved-Sun data. <BR />Results:
  Here, we demonstrate that the empirical factors derived by Chaplin et
  al. (2004, A&amp;A, 424, 713) are reproduced by our analysis, but with
  a more marked dependence upon the mode linewidth.

---------------------------------------------------------
Title: Rotation Of The Deep Solar Interior From A Solar Cycle Of
    Gong Data
Authors: Leibacher, John W.; Salabert, D.; Appourchaux, T.; Hill,
   F.; Howe, R.
2007AAS...210.2219L    Altcode: 2007BAAS...39..127L
  We use 3960 days of Global Oscillation Network Group (GONG) data
  to derive the rotation of the deep solar interior. We obtain the
  splitting of low signal-to-noise multiplets - at low radial order
  and low spherical harmonic degree - using the m-averaged spectra - a
  technique that works well even when none of the individual-m spectra are
  clean enough to be fit. Central frequencies and rotational splittings
  are estimated down to l = 1 and 1 mHz. We illustrate here the validity
  of our method and infer the radial rotation profile down to 0.2 solar
  radius. <P />This work utilizes data obtained by the Global Oscillation
  Network Group (GONG) program, managed by the National Solar Observatory,
  which is operated by AURA, Inc. under a cooperative agreement with
  the National Science Foundation. The data were acquired by instruments
  operated by the Big Bear Solar Observatory, High Altitude Observatory,
  Learmonth Solar Observatory, Udaipur Solar Observatory, Instituto de
  Astrofisica de Canarias, and Cerro Tololo Interamerican Observatory.

---------------------------------------------------------
Title: On cross-spectrum capabilities for detecting stellar
    oscillation modes
Authors: Appourchaux, T.; Leibacher, J.; Boumier, P.
2007A&A...463.1211A    Altcode:
  Aims:Long-lived stellar oscillation modes are usually detected using
  Fourier transforms of time series of stellar radial velocities or
  brightness. It is commonly thought that one could use the cross spectrum
  of the two signals, or alternatively use the interleaved series of a
  single signal, to considerably improve the detection level by reducing
  the noise level. <BR />Methods: We use a statistical analysis of the
  cross spectrum to compute its mean value and rms value, and use the
  associated signal-to-noise ratio for stochastically excited modes. <BR
  />Results: Here, we demonstrate that the gain in the signal-to-noise
  ratio can indeed be improved for modes with a shorter lifetime than
  the observation time, but not those with a longer lifetime than the
  observation time.

---------------------------------------------------------
Title: EUI, The Ultraviolet Imaging Telescopes Of Solar Orbiter
Authors: Hochedez, J. -F.; Appourchaux, T.; Defise, J. -M.; Harra,
   L. K.; Schühle, U.; Auchère, F.; Curdt, W.; Hancock, B.; Kretzschmar,
   M.; Lawrence, G.; Leclec'h, J. -C.; Marsch, E.; Mercier, R.; Parenti,
   S.; Podladchikova, E.; Ravet, M. -F.; Rochus, P.; Rodriguez, L.;
   Rouesnel, F.; Solanki, S.; Teriaca, L.; Van Driel, L.; Vial, J. -C.;
   Winter, B.; Zhukov, A.
2007ESASP.641E..33H    Altcode:
  The scientific objectives of Solar Orbiter rely ubiquitously on EUI,
  its suite of solar atmosphere imaging telescopes. In the configuration
  discussed here, EUI includes three co-aligned High Resolution Imagers
  (HRI) and one Full Sun Imager (FSI). FSI and two HRIs observe in extreme
  ultraviolet passbands, dominated by coronal emission. Another HRI is
  designed for the hydrogen Lyman α radiation in the far UV, imaging the
  Chromosphere and the lower Transition Region. The current EUI design
  and some of its development challenges are highlighted. EUI profits from
  co-rotation phases, solar proximity and departure from the ecliptic. In
  synergy with the other S.O. payload, EUI probes the dynamics of the
  solar atmosphere, provides context data for all investigations and helps
  to link in-situ and remote-sensing observations. In short, it serves all
  four top-level goals of the mission. For these reasons, the EUI suite
  is keenly anticipated in the European scientific community and beyond.

---------------------------------------------------------
Title: Design Of A Fabry Perot Interferometer For The VIM Instrument
    Aboard Solar Orbiter
Authors: Trosseille, C.; Appourchaux, T.; Martinez Pillet, V.
2007ESASP.641E..85T    Altcode:
  The spectral analyser of the Visible light Imager and Magnetograph
  (VIM) is a critical device whose concept is dependent on scientific
  requirements and technical trade-offs, which are directly driven by
  the nature of the mission. Here, we report on the choices that were
  made to fulfill the scientific needs, while constantly keeping an eye
  on feasibility. We also list the critical points and remaining issues
  that should be investigated and addressed properly in further work.

---------------------------------------------------------
Title: Evaluation of the Scientific Performances for the Seismology
    Programme
Authors: Appourchaux, T.; Berthomieu, G.; Michel, E.; Ballot, J.;
   Barban, C.; Baudin, F.; Boumier, P.; De Ridder, J.; Floquet, M.;
   Garcia, R. A.; Garrido, R.; Goupil, M. -J.; Lambert, P.; Lochard,
   J.; Mazumdar, A.; Neiner, C.; Poretti, E.; Provost, J.; Roxburgh,
   I.; Samadi, R.; Toutain, T.
2006ESASP1306..429A    Altcode:
  The Data Analysis Team of the Seismology Working Group of COROT
  performed several hare-and-hound exercises. These exercises aimed at
  putting the team in a situation as if they would analyze data coming
  out of the COROT spacecraft. In total the team performed five different
  exercises simulating solar-like stars (HH#1, HH#2, HH#3), classical
  pulsators (HH#5), validating seismic calibration of stellar model (HH#2,
  HH#3) and pushing the limit of detection (HH#4). This paper tries both
  to serve as a summary and as a portal to other publications of the DAT.

---------------------------------------------------------
Title: Data Analysis Tools for the Seismology Programme
Authors: Appourchaux, T.; Berthomieu, G.; Michel, E.; Aerts, C.;
   Ballot, J.; Barban, C.; Baudin, F.; Boumier, P.; De Ridder, J.;
   Floquet, M.; Garcia, R. A.; Garrido, R.; Goupil, M. -J.; Lambert,
   P.; Lochard, J.; Neiner, C.; Poretti, E.; Provost, J.; Roxburgh, I.;
   Samadi, R.; Toutain, T.
2006ESASP1306..377A    Altcode:
  Tools developed by helioseismologists and by classical-pulsator
  astronomers have been used in the hare-and-hound exercises for having
  a several different ways of deriving the oscillation mode parameters
  such as frequency or amplitude. These tools are used for deriving what
  we call recipes that will allow us to obtain the mode parameters from
  light curves either for solar-like stars or for classical pulsators. The
  recipes are used for tagging the mode parameters as being those of
  COROT. They will be used as reference or yardstick for other fitting
  strategies. We will also address the issue of mode detection. Additional
  tools such as time-frequency analysis will be presented.

---------------------------------------------------------
Title: The Research and Scientific Support Department of ESA and CoRoT
Authors: Fridlund, M.; Beaufort, T.; Favata, F.; Foing, B.; Gimenéz,
   A.; Gondoin, P.; Johlander, B.; Smit, H.; Sunter, W.; Appourchaux, T.
2006ESASP1306..133F    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The Seismology Programme of CoRoT
Authors: Michel, E.; Baglin, A.; Auvergne, M.; Catala, C.; Aerts,
   C.; Alecian, G.; Amado, P.; Appourchaux, T.; Ausseloos, M.; Ballot,
   J.; Barban, C.; Baudin, F.; Berthomieu, G.; Boumier, P.; Bohm, T.;
   Briquet, M.; Charpinet, S.; Cunha, M. S.; De Cat, P.; Dupret, M. A.;
   Fabregat, J.; Floquet, M.; Fremat, Y.; Garrido, R.; Garcia, R. A.;
   Goupil, M. -J.; Handler, G.; Hubert, A. -M.; Janot-Pacheco, E.;
   Lambert, P.; Lebreton, Y.; Lignieres, F.; Lochard, J.; Martin-Ruiz,
   S.; Mathias, P.; Mazumdar, A.; Mittermayer, P.; Montalban, J.;
   Monteiro, M. J. P. F. G.; Morel, P.; Mosser, B.; Moya, A.; Neiner,
   C.; Nghiem, P.; Noels, A.; Oehlinger, J.; Poretti, E.; Provost, J.;
   Renan de Medeiros, J.; De Ridder, J.; Rieutord, M.; Roca-Cortes, T.;
   Roxburgh, I.; Samadi, R.; Scuflaire, R.; Suarez, J. C.; Theado, S.;
   Thoul, A.; Toutain, T.; Turck-Chieze, S.; Uytterhoeven, K.; Vauclair,
   G.; Vauclair, S.; Weiss, W. W.; Zwintz, K.
2006ESASP1306...39M    Altcode: 2008arXiv0811.1080M
  We introduce the main lines and specificities of the CoRoT Seismology
  Core Programme. The development and consolidation of this programme has
  been made in the framework of the CoRoT Seismology Working Group. With a
  few illustrative examples, we show how CoRoT data will help to address
  various problems associated with present open questions of stellar
  structure and evolution.

---------------------------------------------------------
Title: SIMU-LC: A Light-Curve Simulator for CoRoT
Authors: Baudin, F.; Samadi, R.; Appourchaux, T.; Michel, E.
2006ESASP1306..403B    Altcode:
  In order to prepare the analysis of COROT data, it has been decided
  to build a simple tool to simulate the expected light curves. This
  simulation tools takes into account both instrumental constraints and
  astrophysical inputs for the COROT targets. For example, granulation and
  magnetic activity signatures are simulated, as well as p modes, with
  the expected photon noise. However, the simulations rely sometimes on
  simple approach of these phenomenons, as the main goal of this tool is
  to prepare the analysis in the case of COROT data and not to perform
  the most realistic simulations of the different phenomenons.

---------------------------------------------------------
Title: The internal structure of the Sun inferred from g modes and
    low-frequency p modes
Authors: Elsworth, Y. P.; Baudin, F.; Chaplin, W; Andersen, B;
   Appourchaux, T.; Boumier, P.; Broomhall, A. -M.; Corbard, T.;
   Finsterle, W.; Fröhlich, C.; Gabriel, A.; García, R. A.; Gough,
   D. O.; Grec, G.; Jiménez, A.; Kosovichev, A.; Provost, J.; Sekii,
   T.; Toutain, T.; Turck-Chièze, S.
2006ESASP.624E..22E    Altcode: 2006soho...18E..22E
  The Phoebus group is an international collaboration of
  helioseismologists, its aim being to detect low-frequency solar g
  modes. Here, we report on recent work, including the development and
  application of new techniques based on the detection of coincidences
  in contemporaneous datasets and the asymptotic properties of the g-mode
  frequencies. The length of the time series available to the community is
  now more than ten years, and this has reduced significantly the upper
  detection limits on the g-mode amplitudes. Furthermore, low-degree p
  modes can now be detected clearly at frequencies below 1000 μHz.

---------------------------------------------------------
Title: Rotation inversions of artificial solarFLAG Sun-as-a-star data
Authors: Chaplin, W. J.; Sekii, T.; Appourchaux, T.; Baudin, F.;
   Boumier, P.; Corbard, T.; Elsworth, Y.; Fletcher, S. T.; Garcia,
   R. A.; Jiménez-Reyes, S. J.; Lazrek, M.; New, R.; Salabert, D.;
   Toutain, T.; Wachter, R.
2006ESASP.624E..82C    Altcode: 2006soho...18E..82C
  No abstract at ADS

---------------------------------------------------------
Title: Recent Progresses on g-Mode Search
Authors: Appourchaux, T.; Andersen, B.; Baudin, F.; Boumier, P.;
   Broomhall, A. -M.; Chaplin, W.; Corbard, T.; Elsworth, Y.; Finsterle,
   W.; Fröhlich, C.; Gabriel, A.; Garcia, R.; Gough, D. O.; Grec, G.;
   Jiménez, A.; Kosovichev, A.; Provost, J.; Sekii, T.; Toutain, T.;
   Turck-Chièze, S.
2006ESASP.617E...2A    Altcode: 2006soho...17E...2A
  No abstract at ADS

---------------------------------------------------------
Title: Solar FLAG hare and hounds: on the extraction of rotational
    p-mode splittings from seismic, Sun-as-a-star data
Authors: Chaplin, W. J.; Appourchaux, T.; Baudin, F.; Boumier, P.;
   Elsworth, Y.; Fletcher, S. T.; Fossat, E.; García, R. A.; Isaak,
   G. R.; Jiménez, A.; Jiménez-Reyes, S. J.; Lazrek, M.; Leibacher,
   J. W.; Lochard, J.; New, R.; Pallé, P.; Régulo, C.; Salabert, D.;
   Seghouani, N.; Toutain, T.; Wachter, R.
2006MNRAS.369..985C    Altcode: 2006MNRAS.tmp..515C; 2006astro.ph..6748C
  We report on results from the first solar Fitting at Low-Angular
  degree Group (solar FLAG) hare-and-hounds exercise. The group
  is concerned with the development of methods for extracting the
  parameters of low-l solar p-mode data (`peak bagging'), collected by
  Sun-as-a-star observations. Accurate and precise estimation of the
  fundamental parameters of the p modes is a vital pre-requisite of all
  subsequent studies. Nine members of the FLAG (the `hounds') fitted
  an artificial 3456-d data set. The data set was made by the `hare'
  (WJC) to simulate full-disc Doppler velocity observations of the
  Sun. The rotational frequency splittings of the l = 1, 2 and 3 modes
  were the first parameter estimates chosen for scrutiny. Significant
  differences were uncovered at l = 2 and 3 between the fitted splittings
  of the hounds. Evidence is presented that suggests this unwanted bias
  had its origins in several effects. The most important came from the
  different way in which the hounds modelled the visibility ratio of
  the different rotationally split components. Our results suggest that
  accurate modelling of the ratios is vital to avoid the introduction of
  significant bias in the estimated splittings. This is of importance
  not only for studies of the Sun, but also of the solar analogues
  that will be targets for asteroseismic campaigns. <P />Solar FLAG
  URL: http://bison.ph.bham.ac.uk/~wjc/Research/FLAG.html <P />E-mail:
  wjc@bison.ph.bham.ac.uk ‡ <P />George Isaak passed away in 2005 June
  5, prior to the completion of this work. He is greatly missed by us all.

---------------------------------------------------------
Title: Can we finally solve the problems of "Coronal Heating " and
    "Solar Wind Acceleration" in the Cosmic Vision era ?
Authors: Maksimovic, M.; Appourchaux, T.; Aulanier, G.; Chust, T.;
   Dudok de Wit, T.; Klein, K. L.; Krasnoselskikh, V.; Louarn, P.; Roux,
   A.; Vial, J. C.
2006cosp...36.2999M    Altcode: 2006cosp.meet.2999M
  Since the discovery of the corona s million-degree temperature in the
  1940s and the supersonic solar wind in the early 1960s major efforts
  have been made to discover the physical mechanisms that could explain
  these two observations These efforts have led to a tremendous increase
  in our knowledge of our neighbour star the inner heliosphere and the
  Sun-Earth connections Unfortunately these efforts haven t allowed to
  provide a definitive answer to these questions Why such a situation On
  one hand the remote-sensing strategy has tried to probe the coronal
  properties by basically analysing the photons emitted or absorbed
  by the Sun s atmosphere With this regards limitations occur on both
  theoretical ground physics of the coupling between photons and plasma
  and experimental ground limited number of observables such as spectral
  lines or the hardly solvable problem of the line of sight integration
  On the other hand solar wind in-situ measurements have had access to
  the very detailed state of the local plasma properties full particles
  velocity distribution functions observations of the electromagnetic
  plasma fluctuations over a huge frequency range but at locations
  far from the corona and the solar wind acceleration regions Moreover
  it has been realized more recently that the magnetic field plays a
  fundamental role in shaping the low corona and channelling the energy
  inputs Unfortunately the measurement of the full magnetic vector in
  the corona is a very difficult enterprise and this lack of information
  hampers all on-going modelling efforts Given

---------------------------------------------------------
Title: The Beleinos cornerstone: the Sun, the star close to Earth
Authors: Appourchaux, T.; Auchère, F.; Bocchialini, K.; Bonnet,
   R. M.; Gabriel, A.; Vial, J. -C.
2005ESASP.588..389A    Altcode: 2005tssc.conf..389A
  No abstract at ADS

---------------------------------------------------------
Title: The magnetism of the solar interior for a complete MHD
    solar vision
Authors: Turck-Chièze, S.; Appourchaux, T.; Ballot, J.; et al.
2005ESASP.588..193T    Altcode: 2005astro.ph.10854T; 2005tssc.conf..193T
  The solar magnetism is no more considered as a purely superficial
  phenomenon. The SoHO community has shown that the length of the
  solar cycle depends on the transition region between radiation and
  convection. Nevertheless, the internal solar (stellar) magnetism
  stays poorly known. Starting in 2008, the American instrument HMI/SDO
  and the European microsatellite PICARD will enrich our view of the
  Sun-Earth relationship. Thus obtaining a complete MHD solar picture is
  a clear objective for the next decades and it requires complementary
  observations of the dynamics of the radiative zone. For that ambitious
  goal, space prototypes are being developed to improve gravity mode
  detection. The Sun is unique to progress on the topology of deep
  internal magnetic fields and to understand the complex mechanisms which
  provoke photospheric and coronal magnetic changes and possible longer
  cycles important for human life. We propose the following roadmap in
  Europe to contribute to this "impressive" revolution in Astronomy and
  in our Sun-Earth relationship: SoHO (1995-2007), PICARD (2008-2010),
  DynaMICS (2009-2017) in parallel to SDO (2008-2017) then a world-class
  mission located at the L1 orbit or above the solar poles.

---------------------------------------------------------
Title: Working group report on Asteroseismology and stellar activity
    from Dome C
Authors: Bouchy, F.; Mosser, B.; Catala, C.; Appourchaux, T.; Bouvier,
   J.; Chadid, M.; Donati, J. F.; Fossat, E.; Schmider, F. X.; Thevenin,
   F.; Vauclair, G.
2005sf2a.conf..329B    Altcode:
  This paper presents the conclusions of the working group for stellar
  physics observations at the Dome-C station in Antarctica. It summarizes
  the advantages of Dome-C for asteroseismology and stellar activity,
  identifies strategies and possible instrumental projects to be conducted
  there, and concludes with recommendations for the development of stellar
  observations. The conclusions are based on the fact that continuous
  observations over several weeks or months without breaks due to the
  diurnal cycle are fundamental for programs of stellar physics and
  especially for asteroseismology and stellar activity. Therefore, Dome-C
  appears to be a unique ground-based site offering ideal conditions
  for continuous observations.

---------------------------------------------------------
Title: The life of stars and their planets
Authors: Catala, C.; Aerts, C.; Aigrain, S.; Antonello, E.;
   Appourchaux, T.; Auvergne, M.; Baglin, A.; Barge, P.; Barstow, M. A.;
   Baudin, F.; Boumier, P.; Collier Cameron, A.; Christensen-Dalsgaard,
   J.; Cutispoto, G.; Deeg, H.; Deleuil, M.; Desidera, S.; Donati, J. -F.;
   Favata, F.; Foing, B. H.; Gameiro, J. F.; Garcia, R.; Garrido, F.;
   Horne, K.; Lanza, A. F.; Lanzafame, A. C.; Lecavelier Des Etangs,
   A.; Léger, A.; Mas-Hesse, M.; Messina, S.; Micela, G.; Michel, E.;
   Monteiro, M. J. P. F. G.; Mosser, B.; Noels, A.; Pagano, I.; Piotto,
   G.; Poretti, E.; Rauer, H.; Roca-Cortes, T.; Rodono, M.; Rouan, D.;
   Roxburgh, I.; Schneider, J.; Strassmeier, K.; Turck-Chièze, S.;
   Vauclair, S.; Vidal-Madjar, A.; Weiss, W. W.; Wheatley, P.
2005ESASP.588...99C    Altcode: 2005tssc.conf...99C
  We lack a reliable scenario for the formation and evolution of stars
  and their planetary systems, involving key factors such as magnetic
  fields and turbulence. We present the case for a mission concept that
  will clarify these problems and give us a global view of the evolution
  of combined star and planetary systems. This will be achieved by
  simultaneously addressing the search for planetary transits in front
  of a large number of stars, including many nearby stars, the study of
  their internal structure and evolution via asteroseismology, and that
  of their magnetic activity, via UV monitoring.

---------------------------------------------------------
Title: The luminosity oscillations imager, a space instrument:
    from design to science
Authors: Appourchaux, Thierry
2005pmds.book..185A    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Innovative designs for the imaging suite on Solar Orbiter
Authors: Auchere, Frederic; Song, Xueyen; Rouesnel, Frederic;
   Appourchaux, Thierry; Fourmon, Jean-Jacques; Le Clec'h,
   Jean-Christophe; Berthe, Michel; Defise, Jean-Marc; Mazy, Emmanuel;
   Rochus, Pierre L.; Mercier, Raymond; Ravet, Marie-Francoise
2005SPIE.5901..298A    Altcode:
  Orbiting around the Sun on an inclined orbit with a 0.2 UA perihelion,
  the Solar Orbiter probe will provide high resolution views of the Sun
  from various angles unattainable from Earth. Together with a set of high
  resolution imagers, the Full Sun Imager is part of the EUV Imaging suite
  of the Solar Orbiter mission. The mission's ambitious characteristics
  draw severe constraints on the design of these instruments. We present
  a photometrically efficient, compact, and lightweight design for the
  Full Sun Imager. With a 5 degrees field of view, this telescope will
  be able to see the global solar coronal structure from high viewing
  angles. Thermal solutions reducing the maximum power trapped in the
  High Resolution Imagers are also proposed.

---------------------------------------------------------
Title: Inferred acoustic rates of solar p modes from several
    helioseismic instruments
Authors: Baudin, F.; Samadi, R.; Goupil, M. -J.; Appourchaux, T.;
   Barban, C.; Boumier, P.; Chaplin, W. J.; Gouttebroze, P.
2005A&A...433..349B    Altcode:
  Acoustic rates of excitation of solar p modes can be estimated from
  observations in order to place constraints on the modelling of the
  excitation process and the layers where it occurs in the star. For
  several reasons (including a poor signal to noise ratio and mode
  overlap), this estimation is difficult. In this work, we use three
  completely independent datasets to obtain robust estimates in the
  solar case for ℓ=1 modes. We also show that the height in the solar
  atmosphere where the modes are observed must be taken into account. Our
  three sets of results are shown to be consistent, particularly in
  the lower part of the p-mode spectrum (from 1.8 mHz to 2.8 mHz). At
  higher frequencies, the agreement is not as good, because of a larger
  dispersion of the measurements and also because of some systematic
  differences which might be due to observation height estimation or to
  a systematic influence of the noise.

---------------------------------------------------------
Title: On measuring planetary winds using high-resolution spectroscopy
    in visible wavelengths
Authors: Civeit, T.; Appourchaux, T.; Lebreton, J. -P.; Luz, D.;
   Courtin, R.; Neiner, C.; Witasse, O.; Gautier, D.
2005A&A...431.1157C    Altcode:
  We present a new method that uses high-resolution spectroscopy in
  the visible wavelength domain to measure planetary winds. A rotating
  atmosphere illuminated by the Sun induces a Doppler shift in the
  back-scattered solar light. Its analysis with a cross-dispersed echelle
  spectrometer allows the direct determination of both the wind speed
  and direction. We describe in this paper the image and data processing
  algorithms used in the method and implemented in a data reduction
  and analysis package. Since the velocity of planetary winds leads to
  Doppler shifts smaller than the width of the solar lines, accurate
  Doppler measurements are performed by running the algorithm proposed
  by [CITE], which is an optimum technique using the full available
  spectral information. We apply the method to Io as a test case, a
  small slowly-rotating body with no atmosphere, to measure its solid
  rotation. The observations span wavelengths from 414 to 621 nm and were
  carried out with the Ultraviolet and Visual Echelle Spectrograph (UVES)
  on the 8.2 m Kueyen unit at the Very Large Telescope (VLT ESO). The
  results we obtain for Io validate the principle of the method by
  optimally measuring the well-known surface rotational velocity of this
  moon, with an uncertainty smaller than 2 m s<SUP>-1</SUP>. However,
  the analysis of the set of observations shows that systematic errors are
  large and one needs to consider the retrieved velocity as a lower limit.

---------------------------------------------------------
Title: On the detection of pure sine waves embedded in a spectrum
    of stochastically excited p modes
Authors: Moreira, O.; Appourchaux, T.; Berthomieu, G.; Toutain, T.
2005MNRAS.357..191M    Altcode: 2005MNRAS.tmp...16M
  The mode identification and fitting of solar oscillations provide
  an observational tool to derive the physical properties of the Sun's
  interior. What has been devised for helioseismology can now be used for
  future asteroseismology ground-based instruments and space missions,
  such as the High-Accuracy Radial Velocity Planetary Searcher (HARPS)
  and Convection, Rotation and Planetary Transits (COROT). In the coming
  decade, numerous stars will be observed for which new tools will be
  needed. For instance, it is very likely that g and p modes will be
  detected, rendering the identification difficult. In addition, modes
  having both characteristics, known as mixed modes, are also likely to
  be detected in evolved stars; these latter modes are crucial for the
  understanding of the internal structure of the stars as they propagate
  deeply inside the stars, unlike the p modes. Unfortunately, the mixing
  will not only occur physically but also in the frequency domain: mixed
  modes will appear very close to stochastically excited p modes. In this
  paper, we have devised a new technique for detecting long-lived modes
  (mixed or g modes) embedded in a common p-mode spectrum. The technique
  has been validated using Monte Carlo simulations. In the framework of
  the hare-and-hound exercise of COROT, this technique has been applied
  to synthetic time series of the evolved solar-like star HD 57006. The
  results show that we can detect most of the mixed modes embedded by
  the hare. We also discuss the impact of how the long-lived modes are
  excited on the detection level. The technique described here can be
  applied to stars with a mass greater than 1.2 M<SUB>solar</SUB>, having
  evolved possibly beyond the terminal-age main sequence, such as Procyon.

---------------------------------------------------------
Title: Characterization of the Zonal Wind Flow in the Upper Atmosphere
    of Titan with the VLT
Authors: Courtin, Régis; Luz, David; Gautier, Daniel; Appourchaux,
   Thierry; Lebreton, Jean-Pierre; Ferri, Francesca; Lara, Luisa; Hourdin,
   Frédéric; Kaufer, Andreas
2005HiA....13..897C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: On detecting short-lived p modes in a stellar oscillation
    spectrum
Authors: Appourchaux, T.
2004A&A...428.1039A    Altcode:
  The false alarm probability for detecting peaks embedded in a power
  spectrum of noise was given by \cite{Scargle82}. This test has been
  used in helioseismology to detect long-lived modes such as g modes
  \citep{TA2000}. With the development of asteroseismology, there is
  now a need to define a similar test but for short-lived p modes. In
  this article, I define a false alarm test for detecting short-lived p
  modes, and I give the probability of detecting such modes given their
  signal-to-noise ratio, their linewidths and the duration of observation.

---------------------------------------------------------
Title: Flag Hare-And Exercise: on the Extraction of Sectoral Mode
    Splittings from Full-Disc Sun-As Data
Authors: Chaplin, W. J.; Appourchaux, T.; Baudin, F.; Boumier, P.;
   Elsworth, Y.; Fletcher, S. T.; Fossat, E.; García, R. A.; Isaak,
   G. R.; Jiménez, A.; Jiménez-Reyes, S. J.; Lazrek, M.; Lochard, J.;
   New, R.; Pallé, P.; Régulo, C.; Salabert, D.; Toutain, T.
2004ESASP.559..356C    Altcode: 2004soho...14..356C
  No abstract at ADS

---------------------------------------------------------
Title: a Radial Velocity Search for P-Modes in VIR
Authors: Martic, M.; Lebrun, J. C.; Appourchaux, T.; Schmitt, J.
2004ESASP.559..563M    Altcode: 2004astro.ph..9126M; 2004soho...14..563M
  Spectroscopic high-resolution observations were performed with
  fiber-fed cross-dispersed echelle spectrographs in order to measure
  the fluctuations in radial velocities of a sample of bright stars
  that are likely to undergo solar-like oscillations. Here we report
  the results for beta Vir (HR4540) from two observing runs carried out
  in February 2002 with FEROS at the ESO 1.52 m telescope in La Silla
  (Chile) and ELODIE spectrograph at 1.93 OHP telescope (Observatoire de
  Haute Provence, France). The analysis of the time series of Doppler
  shifts from both sites has revealed the presence of an excess power
  around 1.7 mHz. We discuss the interpretation of this data set in
  terms of possible p-mode oscillations.

---------------------------------------------------------
Title: On comparing estimates of low-l solar p-mode frequencies from
    Sun-as-a-star and resolved observations
Authors: Chaplin, W. J.; Appourchaux, T.; Elsworth, Y.; Isaak, G. R.;
   Miller, B. A.; New, R.
2004A&A...424..713C    Altcode:
  Low-angular-degree (low-l) solar p modes provide a sensitive probe
  of the radiative interior and core of the Sun. Estimates of their
  centroid frequencies can be used to constrain the spherically symmetric
  structure of these deep-lying layers. The required data can be extracted
  from two types of observation: one where the modes are detected in
  integrated sunlight, i.e., a Sun-as-a-star view; and a second where
  the visible disc is imaged onto many pixels, and the collected images
  then decomposed into their constituent spherical harmonics. While the
  imaging strategy provides access to all of the individual components
  of a multiplet, the Sun-as-a-star technique is sensitive to only
  about two thirds of these (average over l=0 to 3) with those modes
  that are detected having different levels of visibility. Because
  the various components can have contrasting spatial structure over
  the solar surface, they can respond very differently to changes in
  activity along the solar cycle. Since the Sun-as-a-star and resolved
  analyses take as input a different “subset” of modes, the extracted
  frequency estimates are expected to differ depending upon the phase
  of the cycle. Differences also arise from the types of models used to
  fit the modes. Here, we present expressions that allow the sizes of
  these differences to be predicted.

---------------------------------------------------------
Title: p-mode frequencies in solar-like stars.  I. Procyon A
Authors: Martić, M.; Lebrun, J. -C.; Appourchaux, T.; Korzennik, S. G.
2004A&A...418..295M    Altcode: 2004astro.ph..3035M
  As a part of an on-going program to explore the signature of p-modes
  in solar-like stars by means of high-resolution absorption line
  spectroscopy, we have studied four stars (α CMi, η Cas A, ζ Her A
  and β Vir). We present here new results from two-site observations of
  Procyon A acquired over twelve nights in 1999. Oscillation frequencies
  for l=1 and 0 (or 2) p-modes are detected in the power spectra of
  these Doppler shift measurements. A frequency analysis points out the
  difficulties of the classical asymptotic theory in representing the
  p-mode spectrum of Procyon A. <P />Based on observations obtained at
  the Observatoire de Haute-Provence (CNRS, France) and at the Whipple
  Observatory (Arizona, USA).

---------------------------------------------------------
Title: Solar p-mode frequencies at ℓ=2: What do analyses  of
    unresolved observations actually measure?
Authors: Chaplin, W. J.; Appourchaux, T.; Elsworth, Y.; Isaak, G. R.;
   Miller, B. A.; New, R.; Toutain, T.
2004A&A...416..341C    Altcode:
  We have studied in detail the extraction of estimates of ℓ=2 p-mode
  frequencies from unresolved observations of the visible disc of the
  Sun. Examples of data of this type include ground-based observations
  made by the Birmingham Solar-Oscillations Network (BiSON), and
  space-borne observations made by the GOLF and VIRGO/SPM instruments
  on board the ESA/NASA SOHO satellite. The fitting of the modes is
  complicated in practice by the asymmetric arrangement in frequency
  of the three components (m=-2, 0 and 2) that are prominent in such
  data. In order to investigate the effect of this we used a series of
  10-yr artificial datasets into which varying degrees of asymmetry were
  introduced. The sets were designed to mimic the characteristics of the
  BiSON and GOLF data, and were analyzed both with and without the BiSON
  window function from the period 1992 through 2001. Since reliable
  estimates of the asymmetry have only recently been extracted from
  unresolved observations (Chaplin et al. \cite{Chaplin03}a) it has for a
  long time been standard practice to fit the ℓ=2 modes to a model that
  assumes a symmetrically arranged multiplet. We have tested the impact
  of this on the accuracy of the extracted frequencies. Furthermore,
  we demonstrate that asymmetric models can be successfully applied,
  provided the data are of sufficient length and quality. We also discuss
  the implications of our simulations for analyses of real solar data.

---------------------------------------------------------
Title: Development of imaging arrays for solar UV observations based
    on wide band gap materials
Authors: Schuehle, Udo H.; Hochedez, Jean-Francois E.; Pau, Jose Luis;
   Rivera, Carlos; Munoz, Elias; Alvarez, Jose; Kleider, Jean-Paul;
   Lemaire, Philippe; Appourchaux, Thierry; Fleck, Bernhard; Peacock,
   Anthony; Richter, Mathias; Kroth, Udo; Gottwald, Alexander; Castex,
   Marie-Claude; Deneuville, Alain; Muret, Pierre; Nesladek, Milos;
   Omnes, Franck; John, Joachim; Van Hoof, Chris
2004SPIE.5171..231S    Altcode:
  Solar ultraviolet imaging instruments in space pose most demanding
  requirements on their detectors in terms of dynamic range, low noise,
  high speed, and high resolution. Yet UV detectors used on missions
  presently in space have major drawbacks limiting their performance
  and stability. In view of future solar space missions we have started
  the development of new imaging array devices based on wide band gap
  materials (WBGM), for which the expected benefits of the new sensors -
  primarily visible blindness and radiation hardness - will be highly
  valuable. Within this initiative, called "Blind to Optical Light
  Detectors (BOLD)", we have investigated devices made of AlGa-nitrides
  and diamond. We present results of the responsivity measurements
  extending from the visible down to extreme UV wavelengths. We discuss
  the possible benefits of these new devices and point out ways to build
  new imaging arrays for future space missions.

---------------------------------------------------------
Title: Global fitting of power spectra of solar-like stars
Authors: Neiner, C.; Appourchaux, T.
2004ESASP.538..373N    Altcode: 2004sshp.conf..373N
  Helioseismology has been able to provide the internal structure of
  the Sun and its dynamics. These inferences have been made possible
  by inverting the frequencies and rotational splitting of the p-mode
  oscillations. Thanks to asteroseismology, similar results can now
  be obtained for stars other than the Sun. For this purpose, we are
  developing a numerical code for global fitting of power spectra. The
  code is currently developed and tested on full-disk integrated solar
  data obtained with the SOHO/LOI instrument. It will then be applied to
  synthetic data from the hare-and-hound exercises of COROT. The final
  goal is to apply the technique to data of solar-like stars obtained
  with the COROT and Eddington satellites to infer the internal structure
  and dynamics of those stars.

---------------------------------------------------------
Title: Mode extraction from time series: from the challenges of
    COROT to those of Eddington
Authors: Appourchaux, T.; Moreira, O.; Berthomieu, G.; Toutain, T.
2004ESASP.538..109A    Altcode: 2004sshp.conf..109A
  With more than 30 years of experience in extraction of eigenmodes from
  power spectra of solar signals, we are now almost ready to apply this
  knowledge onto the forecoming missions: COROT and Eddington. However the
  fitting task differs by 3 orders of magnitude; COROT will be able to get
  time series of stellar light for some 30 stars, while Eddington will
  be able to gather such data for about 50000 stars. While for COROT,
  our current tools can be applied by hand, the case of Eddington is
  significantly more complex. We are looking forward having automatic
  fitting procedures that will allow to recover mode parameters for about
  90% of the solar-like stars. Unfortunately, about 10% of these stars
  will require some more delicate attention that will cost time to take
  care of. We will use the example of the infamous HD 57006, known to
  be quite evolved with a difficult eigenmode spectrum, to explain how
  a star can evolve from an easy-to-fit target (90% of the solar-like
  stars) to a difficult-to-fit (10% of the remaining stars). In the
  latter case, new techniques for detecting narrow peaks (g-mode like)
  out of broad peaks (p-mode like) has been devised in the context of
  the hare-and-hound exercise of COROT. This and other techniques will be
  used to implement the automatic fitting procedure for the remaining 10%
  of Eddington solar-like stars.

---------------------------------------------------------
Title: On Maximum Likelihood Estimation of averaged power spectra
Authors: Appourchaux, T.
2003A&A...412..903A    Altcode:
  It is custom in helioseismology to assume that the power spectra of
  time series of solar radial velocity or of solar intensity have a
  χ<SUP>2</SUP> with 2 degrees of freedom statistics. This assumption
  is regularly used in helioseismology for using Maximum Likelihood
  Estimators for single power spectra with that assumed statistics. When
  independent power spectra are added, it is also custom to assume
  that the resulting power spectra can be approximated by a Gaussian
  distribution. Here we show that this approximation is irrelevant,
  and that the software code developed for fitting single power spectra
  can be used without any approximation after proper normalization of
  the added power spectra.

---------------------------------------------------------
Title: Characterization of the zonal wind in Titan's stratosphere
    with UVES
Authors: Luz, D.; Courtin, R.; Gautier, D.; Appourchaux, T.; Ferri,
   F.; Lebreton, J. -P.; Lara, L.; Hourdin, F.; Kaufer, A.
2003EAEJA.....2941L    Altcode:
  We will report on recent efforts to characterize the zonal wind flow
  in Titan's stratosphere. We have used the UVES echelle spectrometer
  mounted at VLT-UT2 to obtain high-resolution solar spectra reflected
  off Titan. The purpose of the observations, which were done in February
  2002, has been to detect the differential Doppler shift induced by the
  zonal wind flow in the back-scattered solar radiation from the East and
  West limbs of Titan. Since the wind speed should not exceed 200 m/s,
  an absolute detection of the shift on single solar lines is not feasible
  due to the limited spectral resolution of UVES. This is why we apply a
  retrieval scheme developed for stellar accelerometry (Connes P. 1985,
  ApSS 110, 211; Martyc M. et al. 1999, A&amp;A 351, 993) which makes
  use of the full spectral range (∼ 4200 to 6200 Angstroms for the red
  arm of the instrument) and takes into account all the lines present
  in the spectrum. Preliminary results indicate that the wind is prograde.

---------------------------------------------------------
Title: The search for g modes
Authors: Appourchaux, T.
2003ESASP.517..131A    Altcode: 2003soho...12..131A
  The Phoebus group was set up about 5 years ago with the expressed
  purpose to detect the g modes predicted by helioseismology to occur in
  the sun. The current status will be reviewed including new approaches
  proposed by other groups in the field. Over the years, the upper limit
  to g-mode amplitude set by Appourchaux et al. (2000) (10 mm/s at 10 σ)
  has been lowered due to a longer time series as well as new detection
  techniques. Not withstanding these efforts the chance of a positive
  detection still appears remote with the current upper limit still way
  above that predicted by helioseismology. New techniques in particular
  observations involving limb intensity and/or velocity cross-correlations
  against various observables, or even the detection of gravitational
  waves may offer the best hope for a future positive detection.

---------------------------------------------------------
Title: New UV detectors for solar observations
Authors: Hochedez, Jean-Francois E.; Schuehle, Udo H.; Pau, Jose L.;
   Alvarez, Jose; Hainaut, Olivier; Appourchaux, Thierry P.; Auret, F. D.;
   Belsky, Andrei; Bergonzo, Philippe; Castex, M. C.; Deneuville, A.;
   Dhez, Pierre; Fleck, Bernhard; Haenen, Ken; Idir, Mourad; Kleider,
   Jean Paul; Lefeuvre, Elie; Lemaire, Philippe; Monroy, E.; Muret, P.;
   Munoz, Elias; Nesladek, Milos; Omnes, Franck; Pace, Emanuele; Peacock,
   Anthony J.; Van Hoof, Chris A.
2003SPIE.4853..419H    Altcode:
  BOLD (Blind to the Optical Light Detectors) is an international
  initiative dedicated to the development of novel imaging detectors
  for UV solar observations. It relies on the properties of wide bandgap
  materials (in particular diamond and Al-Ga-nitrides). The investigation
  is proposed in view of the Solar Orbiter (S.O.) UV instruments, for
  which the expected benefits of the new sensors -primarily visible
  blindness and radiation hardness- will be highly valuable. Despite
  various advances in the technology of imaging detectors over the last
  decades, the present UV imagers based on silicon CCDs or microchannel
  plates exhibit limitations inherent to their actual material
  and technology. Yet, the utmost spatial resolution, fast temporal
  cadence, sensitivity, and photometric accuracy will be decisive for
  the forthcoming solar space missions. The advent of imagers based on
  wide-bandgap materials will permit new observations and, by simplifying
  their design, cheaper instruments. As for the Solar Orbiter, the
  aspiration for wide-bandgap material (WBGM) based UV detectors is still
  more sensible because the spacecraft will approach the Sun where the
  heat and the radiation fluxes are high. We describe the motivations,
  and present the program to achieve revolutionary flight cameras within
  the Solar Orbiter schedule as well as relevant UV measurements.

---------------------------------------------------------
Title: Characterization of Titan's Zonal Wind Flow with the VLT
Authors: Courtin, Regis; Luz, D.; Gautier, D.; Appourchaux, T.; Ferri,
   F.; Lebreton, J. -P.; Lara, L.; Hourdin, F.; Kaufer, A.
2003IAUSS...1E..33C    Altcode:
  We will report on recent efforts to characteize the zonal wind flow in
  Titan's upper atmosphere. We used the UVES echelle spectrometer at the
  focus of the VLT-UT2 to obtain high-resolution Titan raeflection spectra
  in the visible from 420 to 630 nm. The purpose of the observations
  which were carried out in February 2002 was to detect the differential
  Doppler shift induced by the zonal wind flowin the back-scattered solar
  radiation from the Eastern and Western limbs of Titan. The measured
  spectra were analyzed withthe help of a velocity retrieval scheme
  developed for stellar accelerometry taking into account all of the
  solar lines present in the observed spectral range (Connes 1985 ApSS
  110 211; Martyc et al. 1999 AA 351 993). Preliminary results indicate
  that the wind is prograde and that the wind speed is consistent with
  model predictions.

---------------------------------------------------------
Title: Observations of the Sun's magnetic field during the recent
    solar maximum
Authors: Sanderson, T. R.; Appourchaux, T.; Hoeksema, J. T.; Harvey,
   K. L.
2003JGRA..108.1035S    Altcode:
  We present new observations and analyses of the Sun's magnetic field and
  coronal holes. Using magnetic field observations from the Wilcox Solar
  Observatory, we present a simple means whereby the tilt angle of the
  current sheet can be calculated. We use a data set covering the last 26
  years, which shows for the first time how the dipole component rotated
  once during a full 22-year solar cycle. We show how this influenced
  the current sheet. At solar minimum, the Sun's coronal magnetic field
  was essentially dipolar and aligned parallel to the spin axis. As a
  result, the heliospheric current sheet was flat and had very little
  warp. Around solar maximum, the dipole was perpendicular to the spin
  axis, and the ratio of quadrupole to dipole strength was high for much
  of the time. This meant that the current sheet was tilted and highly
  warped, and reached up to high latitudes. Surprisingly, there were
  also times close to solar maximum when the quadrupole/dipole ratio
  was low, and the current sheet was relatively flat, but still highly
  inclined. We apply for the first time to solar magnetic data a method,
  which quantitatively analyses the quadrupole component of the magnetic
  field. From the terms of the expansion of the observed photospheric
  magnetic field, we compute the position of the poles of the magnetic
  field. We combine for the first time over an extended period of time
  magnetic field data from the Wilcox Solar Observatory with coronal
  hole positions taken from the National Solar Observatory/Kitt Peak. We
  find that the position of the coronal holes followed the motion of the
  poles of the magnetic field as the poles moved over the surface of the
  Sun and that the polar coronal holes broke up into groups of smaller
  like-polarity holes as the poles approached the midlatitude regions
  and the quadrupole became more important. We discuss the implications
  for energetic particle observations at Ulysses.

---------------------------------------------------------
Title: Peak Bagging for Solar-like Stars
Authors: Appourchaux, Thierry
2003Ap&SS.284..109A    Altcode:
  The identification of the low-degree p modes in other stars is the
  challenge of future asteroseismology space missions such as COROT,
  MONS, MOST or Eddington. The identification is based on a priori
  knowledge of the characteristics of the modes. We shall review the most
  common assumptions needed for the identification such as basic stellar
  structure, visibilities, rotational splittings or linewidths. We shall
  describe a few tools needed for facilitating the identification. As
  soon as modes are properly identified, the peakbagging of the mode
  characteristics can be done using Maximum Likelihood Estimation. We
  give examples of the whole process using solar data and hare-and-hound
  exercises performed in the frame work of the COROT project.

---------------------------------------------------------
Title: Hare &amp;Hound Exercise with Simulated COROT Data
Authors: Berthomieu, G.; Appourchaux, T.; COROT Seismology Working
   Group
2003aahd.conf..465B    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Peak finding at low signal-to-noise ratio: low-ℓ solar
    acoustic eigenmodes at n≤9 from the analysis of BiSON data
Authors: Chaplin, W. J.; Elsworth, Y.; Isaak, G. R.; Marchenkov,
   K. I.; Miller, B. A.; New, R.; Pinter, B.; Appourchaux, T.
2002MNRAS.336..979C    Altcode:
  We make use of 9 yr of full-disc helioseismic data - as collected by
  the ground-based Birmingham Solar-Oscillations Network (BiSON) - to
  search for low-frequency, low-angular-degree (low-l) acoustic modes. A
  range of tests are applied to the power spectrum of the observations
  that search for prominent mode-like structure: strong spikes, structure
  spanning several bins signifying the presence of width (from damping),
  and the occurrence of prominent multiplet structure at l&gt;= 1 arising
  principally from the solar rotation and made from several spikes
  separated suitably in frequency. For each test we present analytical
  expressions that allow the probability that the uncovered structure is
  part of the broad-band noise background to be assessed. These make use
  of the cumulative binomial (Bernoulli) distribution and serve to provide
  an objective measure of the significance of the detections. This work
  has to date uncovered nine significant detections of non-broad-band
  origin that we have identified as low-l modes with radial overtone
  numbers n&lt;= 9.

---------------------------------------------------------
Title: Characterization of the Zonal Wind Flow in the Stratosphere
    of Titan with UVES
Authors: Luz, D.; Courtin, R.; Gautier, D.; Ferri, F.; Appourchaux,
   T.; Lebreton, J. -P.; Cabane, M.; Rannou, P.; Hourdin, F.; Lara, L.;
   Kaufer, A.
2002DPS....34.3405L    Altcode: 2002BAAS...34..901L
  We will report on recent efforts to characterize the zonal wind
  flow in Titan's stratosphere. We used the UVES echelle spectrometer
  at the focus of the UT2 of the Very Large Telescope at Paranal,
  Chile, to measure the reflection spectrum of Titan between 4200
  and 6200 angstrom with a resolution of 80,000. The purpose of these
  observations, which were carried out in February 2002, is to detect
  the differential Doppler shift induced by the zonal wind flow between
  the East and West limbs of Titan. However, because the wind speed is
  not expected to exceed 200 m/s, an absolute detection of the Doppler
  shift on isolated solar lines is not feasible, even at the spectral
  resolution of UVES. Therefore, we have made use of a retrieval scheme
  developed for absolute stellar accelerometry (Connes 1985, ApSS 110,
  211; Martic et al. 1999, A&amp;A 351, 993) to extract the velocity
  signal by simultaneously taking into account all the lines present
  in the spectrum. We will describe the method and discuss preliminary
  results. Research supported by the "Programme National de Planetologie"
  of the Institut National des Sciences de l'Univers (France). D. Luz
  acknowledges financial support by the Portuguese Foundation for Science
  and Technology, ref.SFRH-BPD-3630-2000.

---------------------------------------------------------
Title: A search for solar g modes in the GOLF data
Authors: Gabriel, A. H.; Baudin, F.; Boumier, P.; García, R. A.;
   Turck-Chièze, S.; Appourchaux, T.; Bertello, L.; Berthomieu, G.;
   Charra, J.; Gough, D. O.; Pallé, P. L.; Provost, J.; Renaud, C.;
   Robillot, J. -M.; Roca Cortés, T.; Thiery, S.; Ulrich, R. K.
2002A&A...390.1119G    Altcode:
  With over 5 years of GOLF data having some 90% continuity, a new
  attempt has been made to search for possible solar g modes. Statistical
  methods are used, based on the minimum of assumptions regarding the
  solar physics; namely that mode line-widths are small compared with
  the inverse of the observing time, and that modes are sought in the
  frequency interval 150 to 400 mu Hz. A number of simulations are carried
  out in order to understand the expected behaviour of a system consisting
  principally of a solar noise continuum overlaid with some weak sharp
  resonances. The method adopted is based on the FFT analysis of a time
  series with zero-padding by a factor of 5. One prominent resonance at
  284.666 mu Hz coincides with a previous tentative assignment as one
  member of an n=1, l=1, p-mode multiplet. Components of two multiplets,
  previously tentatively identified as possible g-mode candidates from
  the GOLF data in 1998, continue to be found, although their statistical
  significance is shown to be insufficient, within the present assumption
  regarding the nature of the signal. An upper limit to the amplitude
  of any g mode present is calculated using two different statistical
  approaches, according to either the assumed absence (H0 hypothesis)
  or the assumed presence (H1 hypothesis) of a signal. The former yields
  a slightly lower limit of around 6 mm/s.

---------------------------------------------------------
Title: What have we learnt with the Luminosity Oscillations Imager
    over the past 6 years?
Authors: Appourchaux, T.; Andersen, B.; Sekii, T.
2002ESASP.508...47A    Altcode: 2002soho...11...47A
  We summarize what we achieved with 6 years of LOI data. We present
  old as well as new results regarding the p-mode parameters dependence
  upon solar activity. We have also derived the dependence of the solar
  background noise upon solar activity and solar disk position. Inversions
  done using LOI frequencies and higher-degree mode frequencies from
  GONG confirm previous velocity inversions.

---------------------------------------------------------
Title: Observations of The Sun's Coronal Magnetic Field and Coronal
    Holes During The Ulysess Fast Latitude Scan
Authors: Sanderson, T. R.; Appourchaux, T.; Hoeksema, J. T.; Harvey,
   K. L.
2002EGSGA..27..595S    Altcode:
  We have combined magnetic field observations from the Wilcox
  Solar Observatory and coronal holes observations from the Kitt Peak
  Observatory to investigate how the Sun's magnetic field behaved during
  the Ulysses fast latitude scan. <P />Using the dipole and quadrupole
  terms in the expansion of the coronal magnetic field, we show that the
  dipole rotated once every 22-year solar cycle and that the quadrupole
  term reached a maximum at the time of solar maximum. At solar minimum,
  the current sheet was flat and had very little warp, but around solar
  maximum, during the second Ulysses Southern Polar Pass, the ratio
  of quadrupole to dipole strength was high for much of the time. The
  current sheet was tilted and highly warped, and reached up to high
  latitudes. Surprisingly, there were times when the quadrupole/dipole
  ratio was low, and the current sheet was relatively flat, but still
  highly inclined. <P />The site of coronal holes follows the motion of
  the poles of the magnetic field as the poles move over the surface
  of the Sun. The polar coronal hole breaks up into groups of smaller
  like-polarity holes as the poles approach the mid-latitude regions.

---------------------------------------------------------
Title: Variation of acoustic mode centroid frequencies over the
    solar cycle
Authors: Chaplin, W. J.; Appourchaux, T.; Elsworth, Y.; Isaak, G. R.;
   New, R.
2002AdSpR..29.1881C    Altcode:
  Together with a brief historical overview, we use high-quality
  helioseismic data collected by three different observational
  programmes during the declining phase of activity cycle 22, and a
  substantial portion of the rising phase of the current cycle (23),
  to study the phenomenological nature of the cycle-induced (centroid)
  eigenfrequencies. Our analyses (for 1600 ≤ ν ≤ 4000 μHz) make
  use of observations made by the ground-based GONG over the angular
  degree range 4 ≤ l ≤ 150; the ground-based BiSON over 0 ≤ l ≤
  2; and the VIRGO/LOI instrument on board the ESA/NASA SOHO satellite
  over 0 ≤ l ≤ 8. We show that GONG shifts averaged over different
  ranges in l, together with the BiSON and LOI data averaged over
  their full quoted ranges, all scale at a given frequency with the
  normalized mode inertia ratio Q<SUB>nl</SUB> (Christensen-Dalsgaard
  &amp; Berthomieu 1991). This is to be expected if the time-dependent
  perturbation affecting the modes is confined in the surface layers;
  the excellent agreement also reflects favourably on the external
  consistency of the different observations. We have also analyzed
  the frequency dependence of the shifts by fitting a power-law of the
  form δν <SUB>nl</SUB> ∝ (ν <SUB>nl</SUB>/ E<SUB>nl</SUB> to the
  data (where the E<SUB>nl</SUB> are the mode inertias, and α is the
  power-law index to be extracted). Previous studies have suggested that
  a relation with α = 0 provides an adequate description of the shifts
  up to ν ≈ 3500 μHz. However, here we show that while nevertheless
  describing the shifts well up to ∼ 2500 μHz, the linear scaling
  breaks down conspicuously at higher frequencies. Above this threshold,
  the shifts follow a power-law dependence with α ∼ 2.

---------------------------------------------------------
Title: Observations of the Sun's Coronal Magnetic Field and Coronal
    Holes during the Recent Ulysess Second Polar Pass, and Implications
    for Particle Observations
Authors: Sanderson, T. R.; Appourchaux, T.; Hoeksema, J. T.; Harvey,
   K. L.
2001AGUFMSH32A0723S    Altcode:
  We combine magnetic field observations from the Wilcox Solar Observatory
  and coronal hole observations from the National Solar Observatory/ Kitt
  Peak. At solar minimum, the Sun's coronal magnetic field was dipolar and
  aligned along the spin axis. The current sheet was flat and had very
  little warp. Around solar maximum, during the second Ulysses southern
  polar pass, the ratio of quadrupole to dipole strength was high for
  much of the time. This meant that the current sheet was tilted and
  highly warped, and reached up to high latitudes. Using the dipole and
  quadrupole terms from the expansion of the coronal magnetic field,
  we compute the position of the dipole and quadrupole poles. We find
  that the location of coronal holes follows the motion of the poles
  of the magnetic field as the poles move across the surface of the
  Sun. The polar coronal holes break up into groups of smaller holes
  all with the same polarity as the poles approach the mid-latitude
  regions. Surprisingly, there were also times close to solar maximum
  when the quadrupole/dipole ratio was low, and the current sheet was
  relatively flat, but still highly inclined. We discuss the implications
  for the observations of energetic particles at Ulysses.

---------------------------------------------------------
Title: Changes in convective properties over the solar cycle: effect
    on p-mode damping rates
Authors: Houdek, G.; Chaplin, W. J.; Appourchaux, T.;
   Christensen-Dalsgaard, J.; Däppen, W.; Elsworth, Y.; Gough, D. O.;
   Isaak, G. R.; New, R.; Rabello-Soares, M. C.
2001MNRAS.327..483H    Altcode:
  Measurements of both solar irradiance and p-mode oscillation
  frequencies indicate that the structure of the Sun changes with
  the solar cycle. Balmforth, Gough &amp; Merryfield investigated the
  effect of symmetrical thermal disturbances on the solar structure
  and the resulting pulsation frequency changes. They concluded that
  thermal perturbations alone cannot account for the variations in both
  irradiance and p-mode frequencies, and that the presence of a magnetic
  field affecting acoustical propagation is the most likely explanation
  of the frequency change, in the manner suggested earlier by Gough &amp;
  Thompson and by Goldreich et al. Numerical simulations of Boussinesq
  convection in a magnetic field have shown that at high Rayleigh number
  the magnetic field can modify the preferred horizontal length scale
  of the convective flow. Here, we investigate the effect of changing
  the horizontal length scale of convective eddies on the linewidths
  of the acoustic resonant mode peaks observed in helioseismic power
  spectra. The turbulent fluxes in these model computations are obtained
  from a time-dependent, non-local generalization of the mixing-length
  formalism. The modelled variations are compared with p-mode linewidth
  changes revealed by the analysis of helioseismic data collected by
  the Birmingham Solar-Oscillations Network (BiSON); these low-degree
  (low-l) observations cover the complete falling phase of solar activity
  cycle 22. The results are also discussed in the light of observations
  of solar-cycle variations of the horizontal size of granules and with
  results from 2D simulations by Steffen of convective granules.

---------------------------------------------------------
Title: Effects of a gap-filling method on p-mode parameters
Authors: Fierry Fraillon, D.; Appourchaux, T.
2001MNRAS.324.1159F    Altcode:
  The quality of helioseismological ground-based data strongly depends
  on the presence of a gap in the observational window. In order to
  address that problem in the case of full-disc low-degree p-mode
  velocity measurements, Fossat et al. proposed a gap-filling method
  called `Repetitive music'. The autocorrelation function of the velocity
  signal shows a correlation of more than 70 per cent at about 4h because
  of the quasi-periodicity of p-mode peaks in the Fourier spectrum. The
  method then consists of filling gaps of the velocity signal with data,
  when they exist, located 4h before or after. By using Monte Carlo
  simulations, we assess the effects of the gap-filling method on p-mode
  parameters and their errors. A way to remove the modulation in the
  power spectrum resulting from the gap-filling method is proposed; its
  effects on p-mode frequencies, linewidths, amplitudes and asymmetries
  are discussed as a function of frequency and signal-to-noise ratio.

---------------------------------------------------------
Title: The phenomenology of solar-cycle-induced acoustic
eigenfrequency variations: a comparative and complementary analysis
    of GONG, BiSON and VIRGO/LOI data
Authors: Chaplin, W. J.; Appourchaux, T.; Elsworth, Y.; Isaak, G. R.;
   New, R.
2001MNRAS.324..910C    Altcode:
  We use high-quality helioseismic data collected by three different
  observational programmes during the declining phase of activity
  cycle 22,Q7 and a substantial portion of the rising phase of the
  current cycle (23), to study the phenomenological nature of the
  cycle-induced (centroid) eigenfrequency variations. We have analysed
  the frequency dependence of the shifts by fitting a power law of the
  form δν<SUB>nl</SUB>~(ν<SUB>nl</SUB>)<SUP>α</SUP>/E<SUB>nl</SUB>
  to the data (where the E<SUB>nl</SUB> are the mode inertias, and
  α is the power-law index to be extracted). Previous studies have
  suggested that a relation with α=0 provides an adequate description
  of the shifts up to ν~3500μHz. However, here we show that while
  nevertheless describing the shifts well up to ~2500μHz, the linear
  scaling breaks down conspicuously at higher frequencies. Above this
  threshold, the shifts follow a power-law dependence with α~2. Our
  analyses (for 1600&lt;=ν&lt;=4000μHz) make use of observations made
  by the ground-based GONG over the angular degree range 4&lt;=l&lt;=150
  the ground-based BiSON over 0&lt;=l&lt;=2 and the VIRGO/LOI instrument
  on board the ESA/NASA SOHO satellite over 0&lt;=l&lt;=8. We show that
  GONG shifts averaged over different ranges in l, together with the BiSON
  and LOI data averaged over their full quoted ranges, all scale at fixed
  frequency with the normalized mode inertia ratio Q<SUB>nl</SUB>Q1. This
  is to be expected if the solar-cycle perturbation affecting the modes
  is confined in the surface layers; the excellent agreement also reflects
  favourably on the external consistency of the different observations.

---------------------------------------------------------
Title: Observing solar-like oscillations with ELODIE spectrograph
Authors: Martić, M.; Lebrun, J. C.; Schmitt, J.; Bertaux, J. L.;
   Appourchaux, T.
2001sf2a.conf..219M    Altcode:
  We have used ELODIE fiber-fed cross-dispersed echelle spectrograph
  and the 1.93m-telescope of Observatoire de Haute Provence to obtain
  precise Doppler measurements of a sample of bright stars that are
  likely to undergo solar-like oscillations. Here we report the results
  for Procyon from three observing runs (5, 10 and 15 nights) in Decembre
  1997, Novembre 1998, and January 1999. The individual frequencies of
  p-modes were searched in the interval of excess power around 1 mHz found
  in the frequency spectra of each time series. The echelle diagram of
  the observed and predicted p-mode frequencies from the standard model
  (Chaboyer et al., 1999) for Procyon A is presented. We show also some
  preliminary results for two other solar-like stars (eta Cas and z Her).

---------------------------------------------------------
Title: PICARD: solar diameter measure and g-mode search
Authors: Damé, L.; Appourchaux, T.; Berthomieu, G.; Boumier, P.;
   Cugnet, D.; Gelly, B.; Provost, J.; Toutain, T.
2001ESASP.464..321D    Altcode: 2001soho...10..321D
  The PICARD microsatellite mission will provide 3 to 4 years simultaneous
  measurements of the solar diameter, differential rotation and
  solar constant to investigate the nature of their relations and
  variabilities. The major instrument, SODISM, is a whole Sun imaging
  telescope of Ø 110 mm which will deliver an absolute measure
  (better than 4 mas) of the solar diameter and solar shape. Now in
  Phase B, PICARD is expected to be launched by 2005. We recall the
  scientific goals linked to the diameter measurement with emphasis on the
  helioseismology g-mode interest, present the instrument optical concept
  and present design, and give a brief overview of the program aspects.

---------------------------------------------------------
Title: Observing solar-like oscillations: α CMi, η Cas A and ζ
    Her A
Authors: Martić, M.; Lebrun, J. C.; Schmitt, J.; Appourchaux, T.;
   Bertaux, J. L.
2001ESASP.464..431M    Altcode: 2001soho...10..431M
  We have used ELODIE fiber-fed cross-dispersed echelle spectrograph
  and the 1.93m-telescope of Observatoire de Haute Provence to obtain
  precise Doppler measurements of a sample of bright stars that are
  likely to undergo solar-like oscillations. Here we report the results
  for Procyon from three observing runs carried out in December 1997,
  November 1998, and January 1999. We show also some preliminary results
  for two other solar-like stars (η Cas A and ζ Her A).

---------------------------------------------------------
Title: Does the excitation and damping of the acoustic eigenmodes
    vary over the solar cycle? An insight from LOI observations
Authors: Chaplin, W. J.; Appourchaux, T.
2001ESASP.464..601C    Altcode: 2001soho...10..601C
  We have used observations made by the LOI instrument on board the
  ESA/NASA SOHO satellite in order to try and uncover variations in
  the excitation and damping of the low-angular-degree solar acoustic
  eigenmodes over the solar cycle. These data were collected on the rising
  phase of activity cycle 23. We have divided the dataset into independent
  136-d and 1-yr time series and fitted the modes in the complex Fourier
  (frequency) domain to yield estimates of the line widths and amplitudes
  of the modes. The extracted parameters have then been analyzed in order
  to search for solar-cycle-induced variations. Over the range 2600 &lt;=
  ν &lt;= 3600μHz, we uncover a mean implied activity minimum-to-maximum
  increase in the frequency-domain line widths of 21+/-3 per cent; a mean
  decrease of 37+/-3 per cent decrease in the mode heights; and a mean
  decrease of 18+/-4 per cent in the mode powers. Our analysis indicates
  that - at the level of precision of the available data - the rate
  at which energy is supplied to the modes remains constant (uncovered
  variation 3+/-5 per cent). These results are in reasonable agreement
  with recent claims by Chaplin et al. (2000) and Komm, Howe and Hill
  (2000) from analyses of BiSON and GONG data respectively. Furthermore,
  the signs and relative magnitudes of the extracted changes are
  consistent with the speculation made by Chaplin et al. that it is
  alterations in the damping, and not the forcing, of the modes that
  gives rise to the variations observed over the solar activity cycle.

---------------------------------------------------------
Title: Effects of a gap filling method on p-mode parameters
Authors: Fierry Fraillon, D.; Appourchaux, T.
2001ESASP.464..347F    Altcode: 2001soho...10..347F
  The quality of helioseismological ground based data strongly depends
  on the presence of gap in the observational window. In order to
  address that problem in the case of full disk low p-mode velocity
  measurements, Fossat et al. (1999) proposed a gap filling method called
  "Repetitive music". The autocorrelation function of the velocity
  signal shows a correlation of more than 70% at about 4 hours due to
  the quasi-periodicity of p-mode peaks in the Fourier spectrum. The
  method then consists in filling gaps of the velocity signal by data,
  when they exist, located 4 hours before or after. By using Monte Carlo
  simulations we assess the effects of the gap filling method on p-mode
  parameters and their errors. A way to remove the modulation, resulting
  from the gap-filling method, in the power spectrum is proposed; its
  effects on p-mode frequencies, linewidths, amplitudes and asymmetries
  are discussed as a function of both frequency and signal-to-noise
  ratio of the observational data.

---------------------------------------------------------
Title: Results from the luminosity oscillations imager on board SOHO:
    low-degree p-mode parameters for a 4-year data set
Authors: Appourchaux, T.
2001ESASP.464...71A    Altcode: 2001soho...10...71A
  I report on the results from a 4-year VIRGO/LOI data set. I have
  analysed independently four 1-year time series mainly for minimizing
  the effect of solar activity. For l&lt;=3 the p-mode data are fitted
  using the Fourier spectra taking into account the mode leakage and noise
  correlations. For l&gt;=4, the data are fitted using simultaneously the
  power spectra of l=4.7, l=5.8 and l=1.6. The effect of solar activity
  upon frequencies, linewidths, mode amplitude, energy rate, asymmetry
  and splitting is studied. Most of these results in intensity confirms
  earlier measurements made in velocity.

---------------------------------------------------------
Title: Probing the solar cycle: a comparative and complementary
    analysis of GONG BiSON and VIRGO/LOI eigenfrequency shifts
Authors: Chaplin, W. J.; Elsworth, Y.; Isaak, G. R.; New, R.;
   Appourchaux, T.
2001ESASP.464...83C    Altcode: 2001soho...10...83C
  We use high-quality helioseismic data collected by GONG (over 4 &lt;=
  l &lt;= 140), BiSON (0 &lt;= l &lt;= 2) and VIRGO/LOI (0 &lt;= l &lt;=
  8) to study the phenomenological nature of the cycle-induced (centroid)
  eigenfrequency variations. We have analyzed the frequency dependence
  of the shifts by fitting a power-law of the form δν<SUB>nl</SUB> ~
  (ν<SUB>nl</SUB>)<SUP>α</SUP>/E<SUB>nl</SUB> to the data (where the
  E<SUB>nl</SUB> are the mode inertias, and α is the power-law index to
  be extracted). Previous studies have suggested that a relation with
  α = 0 provides an adequate description of the shifts up to ν ≍
  3500 μHz. However, here we show that while nevertheless describing
  the shifts well up to ~2500 μHz, the linear scaling breaks down
  conspicuously at higher frequencies. Above this threshold, the shifts
  follow a power-law dependence with α ~ 2. We also ahow that GONG
  shifts, averaged over different ranges in l together with the BiSON
  and LOI data averaged over their full quoted ranges, all scale at
  fixed frequency with the normalized mode inertia ratio Q<SUB>nl</SUB>
  (Christensen-Dalsgaard &amp; Berthomieu 1991). This is to be expected
  if the solar-cycle perturbation affecting the modes is confined in
  the surface layers; the excellent agreement also reflects favourably
  on the external consistency of the different observations.

---------------------------------------------------------
Title: Dependence on azimuthal order of the amplitudes of low-degree
    p modes
Authors: Fröhlich, C.; Appourchaux, T.; Gough, D. O.
2001ESASP.464..629F    Altcode: 2001soho...10..629F
  The m-dependence of the amplitudes of the multiplets of low-degree p
  modes contains information about the latitudinal distribution of the
  power in the excitation of the oscillations. We present estimates of
  those amplitudes from 4 years of VIRGO/LOI observations. Variation of
  the excitation with magnetic activity is studied.

---------------------------------------------------------
Title: g-mode detection: Where do we stand?
Authors: Appourchaux, T.; Andersen, B.; Berthomieu, G.; Chaplin, W.;
   Elsworth, Y.; Finsterle, W.; Frölich, C.; Gough, D. O.; Hoeksema,
   T.; Isaak, G.; Kosovichev, A.; Provost, J.; Scherrer, P.; Sekii, T.;
   Toutain, T.
2001ESASP.464..467A    Altcode: 2001soho...10..467A
  We review the recent developments in determining the upper limits to
  g-mode amplitudes obtained by SOHO instruments, GONG and BiSON. We
  address how this limit can be improved by way of new helioseismic
  instruments and/or new collaborations, hopefully providing in the not
  too distant future unambiguous g-mode detection.

---------------------------------------------------------
Title: On measuring low-degree p-mode frequency splitting with
    full-disc integrated data
Authors: Appourchaux, T.; Chang, H. -Y.; Gough, D. O.; Sekii, T.
2000MNRAS.319..365A    Altcode:
  The standard method of measuring rotational splitting from solar
  full-disc oscillation data, based on maximum-likelihood fitting of
  multi-Lorentzian profiles to oscillation power spectra, systematically
  overestimates the splitting. One of the reasons is that the maximum
  likelihood estimators (MLE) become unbiased only asymptotically as
  the number of data tends to infinity; for a finite data set they
  are often biased, inducing a systematic error. In this paper we
  assess by Monte Carlo simulations the amount of systematic error
  in the splitting measurement, using artificially generated power
  spectra. The simulations are carried out for multiplets of degree
  S(t) = Σ<SUB>k</SUB>S<SUB>k</SUB>(t), l=1, 2 and 3 with various
  signal-to-noise ratios, linewidths and observing times. We address
  the possible use of non-MLE estimators that could provide a smaller
  or negligible systematic error. The implication for asteroseismology
  is also discussed.

---------------------------------------------------------
Title: Observational Upper Limits to Low-Degree Solar g-Modes
Authors: Appourchaux, T.; Fröhlich, C.; Andersen, B.; Berthomieu, G.;
   Chaplin, W. J.; Elsworth, Y.; Finsterle, W.; Gough, D. O.; Hoeksema,
   J. T.; Isaak, G. R.; Kosovichev, A. G.; Provost, J.; Scherrer, P. H.;
   Sekii, T.; Toutain, T.
2000ApJ...538..401A    Altcode:
  Observations made by the Michelson Doppler Imager (MDI) and Variability
  of solar IRradiance and Gravity Oscillations (VIRGO) on the Solar and
  Heliospheric Observatory (SOHO) and by the ground-based Birmingham
  Solar Oscillations Network (BiSON) and Global Oscillations Network
  Group (GONG) have been used in a concerted effort to search for solar
  gravity oscillations. All spectra are dominated by solar noise in the
  frequency region from 100 to 1000 μHz, where g-modes are expected to be
  found. Several methods have been used in an effort to extract any g-mode
  signal present. These include (1) the correlation of data-both full-disk
  and imaged (with different spatial-mask properties)-collected over
  different time intervals from the same instrument, (2) the correlation
  of near-contemporaneous data from different instruments, and (3) the
  extraction-through the application of complex filtering techniques-of
  the coherent part of data collected at different heights in the solar
  atmosphere. The detection limit is set by the loss of coherence
  caused by the temporal evolution and the motion (e.g., rotation)
  of superficial structures. Although we cannot identify any g-mode
  signature, we have nevertheless set a firm upper limit to the amplitudes
  of the modes: at 200 μHz, they are below 10 mm s<SUP>-1</SUP> in
  velocity, and below 0.5 parts per million in intensity. The velocity
  limit corresponds very approximately to a peak-to-peak vertical
  displacement of δR/R<SUB>solar</SUB>=2.3×10<SUP>-8</SUP> at the
  solar surface. These levels which are much lower than prior claims,
  are consistent with theoretical predictions.

---------------------------------------------------------
Title: Source of excitation of low-l solar p modes: characteristics
    and solar-cycle variations
Authors: Chaplin, W. J.; Appourchaux, T.; Elsworth, Y.; Isaak, G. R.;
   Miller, B. A.; New, R.
2000MNRAS.314...75C    Altcode:
  We investigate various properties of the excitation source that
  is responsible for driving the acoustic p-mode oscillations of the
  Sun. Current prejudice places this in the superadiabatic layer of
  the convection zone. We consider in detail how the precise nature of
  the resonant mode spectrum is modified: (i) as a result of the impact
  of different source-multipole mixtures; and (ii) as a function of the
  radial extent of the source. To do this, we model the observed resonant
  spectra with the solutions to a simple, one-dimensional wave equation
  which is intended to describe the essential elements of the solar
  resonant acoustic cavity. Further, we also fit these models to the
  low-l peaks in a high-resolution power spectrum generated from data
  collected by the Birmingham Solar-Oscillations Network (BiSON). We
  also use the extensive BiSON data set to search for variations in the
  source characteristics over the solar cycle.

---------------------------------------------------------
Title: COROT -- A Unique Database for Low Amplitude Variability
    Between 1 Minute and 150 Days
Authors: Michel, E.; Baglin, A.; Barge, P.; Catala, C.; Auvergne,
   M.; Weiss, W. W.; Appourchaux, T.; Garrido, R.; COROT Team
2000ASPC..203...69M    Altcode: 2000ilss.conf...69M; 2000IAUCo.176...69M
  COROT is a high precision wide field photometry experiment from space,
  funded in the framework of the CNES “Petites Missions” program
  (the PI is A. Baglin). It will observe approximately 30000 objects
  with m<SUB>V</SUB> between 4.5 and 15.5 over long observational
  periods (up to 150 d), with a time sampling between 1 s and 16 min,
  a precision of the order of 10<SUP>-4</SUP> per measurement. The
  scientific objectives are stellar seismology and the search for
  telluric planets. The instrument and the core program have already
  been presented in several places. We here focus on a description of the
  characteristics of the data to be obtained with COROT. The large amount
  of high quality data collected by COROT will constitute rich material
  for several research programs beyond the core program as already defined
  (http://www.astrsp-mrs.fr/www/corot.html). A call for proposal of
  additional programs will be made during Northern Spring 2000.

---------------------------------------------------------
Title: I-V phase difference and gain analysis of GONG full-disk data
Authors: Oliviero, M.; Severino, G.; Straus, T.; Jefferies, S. M.;
   Appourchaux, T.
2000MmSAI..71..999O    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Depth of excitation and reversal of asymmetry of low-l
solar P modes: a complementary analysis of BiSON<SUP>*</SUP> and
    VIRGO/SPM† data
Authors: Chaplin, W. J.; Appourchaux, T.
1999MNRAS.309..761C    Altcode:
  We use the solutions to a simple, one-dimensional wave equation -
  which is intended to describe the essential elements of the solar
  resonant acoustic cavity - as formalistic models to which to fit
  low-l modes in observational helioseismic power spectra. We have
  analysed data collected in velocity, by the ground-based Birmingham
  Solar-Oscillations Network (BiSON), and in intensity, by the full-disc
  VIRGO Sun photometers (SPM) on board the ESA/NASA SOHO satellite. Our
  analysis extracts, as a function of the modal radial overtone number
  n, direct estimates of: the location of the excitation source of the
  acoustic resonances; and the size of the component of the convective
  granulation that is correlated to the observations of the resonances,
  and is responsible for the reversal of asymmetry of the mode profiles
  when different observation techniques are applied (i.e. intensity
  or Doppler velocity measurements). This information is coded in the
  complicated forms of the observed, resonant profiles.

---------------------------------------------------------
Title: Evidence for global pressure oscillations on Procyon
Authors: Martić, M.; Schmitt, J.; Lebrun, J. -C.; Barban, C.; Connes,
   P.; Bouchy, F.; Michel, E.; Baglin, A.; Appourchaux, T.; Bertaux,
   J. -L.
1999A&A...351..993M    Altcode:
  Precise Doppler measurements of the star Procyon (alpha CMi, HR
  2943) have been obtained with the ELODIE fiber-fed cross-dispersed
  echelle spectrograph on the 1.93 m telescope at Observatoire de Haute
  Provence. Here, we present the analysis of data from 10 days observing
  run carried out in November 1998. We detect significant excess in
  the power between 0.5-1.5 mHz in the periodograms of the time series
  of mean Doppler shifts. Observations of eta Cas made with the same
  instrument during the same time interval and in almost identical
  night conditions show a flat spectrum in this frequency range,
  indicating that the excess of Doppler signal seen on Procyon is of
  stellar origin. When data from the whole run are jointly analyzed,
  a period analysis places an upper limit of 0.50-0.60 ms<SUP>-1</SUP>
  for the amplitude of oscillations, while the frequency cutoff is around
  1.5 mHz. The power evidently drops near 0.55 and 1.5 mHz on the average
  of unfiltered power spectra of individual nights, which is consistent
  with the expected p-mode oscillation properties for Procyon. Several
  equispaced peaks in frequency are recurrent in the power spectra of two
  independent segments of 4 and 3 contiguous nights; the most probable
  frequency spacing seems to be 55 mu Hz. In conclusion, we now have an
  instrument set-up which is sufficiently stable and fast to be used for
  a multi-site campaign involving instruments with comparable velocity
  precisions, to detect the oscillation modes of sun-like stars. Based
  on observations obtained at the Observatoire de Haute-Provence (CNRS,
  France)

---------------------------------------------------------
Title: Solar low-degree p-mode parameters from the GONG network
Authors: Rabello-Soares, M. C.; Appourchaux, T.
1999A&A...345.1027R    Altcode:
  Low-degree solar p modes observed by the GONG network have been analysed
  for l &lt;= 6, yielding accurate measurements of their frequencies,
  splittings and linewidths. The results obtained here show significant
  improvement on previous determinations, especially for increasing the
  number of identified modes with l &lt;= 3 and for minimizing the bias
  on the splitting determination and the error bars. A more realistic
  approach was used to fit the helioseismic data assuming that the
  observed spectra are statistically dependent upon one another. This
  is in contrast to what is commonly done and the result is a better
  treatment of the leakage between the modes. Moreover, the effect of
  an imperfect knowledge of the leakage within the elements of the l=1
  multiplets upon their splitting determination is analysed. In addition,
  the effect of the leakage between the modes of different degrees
  upon the p-mode parameters determination is shown, and a procedure
  for `cleaning' the spatial alias is described leading to splitting
  coefficients with smaller systematic errors than before.

---------------------------------------------------------
Title: Space and Time Analysis of the Solar Photospheric Dynamics
    at Moderate-l Values
Authors: Oliviero, M.; Severino, G.; Straus, Th.; Jefferies, S. M.;
   Appourchaux, T.
1999ApJ...516L..45O    Altcode:
  A space-time analysis of 36 days' worth of full-disk intensity and
  velocity images, obtained by the Global Oscillation Network Group,
  is used to produce a high-resolution l-ν phase-difference spectrum
  for the spectral range (4&lt;=l&lt;=2000, 0&lt;=ν&lt;=8.3 mHz). This
  is the first time a phase-difference spectrum has been produced for
  intermediate-l values. The phase differences on the p-mode ridges
  are found to linearly increase from ~65° at 2 mHz up to ~95°
  at 4.7 mHz. Only near 3.9 mHz are the differences close to 90°,
  the theoretically expected phase for adiabatic evanescent waves. The
  phases between the ridges exhibit a steplike behavior in frequency with
  negative values at low frequency and positive values (greater than 90°)
  at high frequency. The negative phase values are consistent with the
  extension to low- and moderate-l values of the plateau-interridge regime
  discovered by Deubner et al. in 1990. However, positive phase values,
  which represent higher phase for the solar background than for the
  acoustic modes, were not expected. An understanding of this observed
  phase-difference behavior will improve our knowledge of the nature of
  the solar background and its interaction with the acoustic p-modes.

---------------------------------------------------------
Title: PICARD: simultaneous measurements of the solar diameter,
    differential rotation, solar constant and their variations
Authors: Damé, Luc; Hersé, Michel; Thuillier, Gérard; Appourchaux,
   Thierry; Crommelynck, Dominique; Dewitte, Steven; Joukoff, Alexandre;
   Fröhlich, Claus; Laclare, Francis; Delmas, Christian; Boumier, Patrick
1999AdSpR..24..205D    Altcode:
  PICARD is a CNES micro-satellite mission due for flight by the end
  of 2002, named after the name of a French astronomer who first
  observed with consistency the solar diameter changes during the
  Maunder minimum in the 16th century. It consists of two instruments
  measuring (i) the solar diameter and differential rotation, and (ii)
  the total solar irradiance. These quantities are fundamental for the
  understanding of the solar-Terrestrial relations, e.g. the influence
  of the Sun on the Earth's climate, and of the internal structure
  of the Sun. The continuous - or nearly continuous - viewing of the
  Sun from an appropriate orbit, the 5 minutes sampling rate and the
  very low noise measurements, will allow g-modes detection and precise
  diameter measurements besides accurately establishing the relationship
  between irradiance and diameter changes. Providing an absolute measure
  of the solar diameter to 1 milliarcsecond, PICARD is the first step
  towards instruments capable of accurate and perennial measurements,
  for the centuries to come, of the solar-terrestrial influence. The
  objectives of the mission, instrument capabilities, observing modes
  and performances are described.

---------------------------------------------------------
Title: The art of fitting p-mode spectra. II. Leakage and noise
    covariance matrices
Authors: Appourchaux, T.; Rabello-Soares, M. -C.; Gizon, L.
1998A&AS..132..121A    Altcode: 1997astro.ph.10131A
  In Part I we have developed a theory for fitting p-mode Fourier spectra
  assuming that these spectra have a multi-normal distribution. We showed,
  using Monte-Carlo simulations, how one can obtain p-mode parameters
  using “Maximum Likelihood Estimators". In this article, hereafter
  Part II, we show how to use the theory developed in Part I for fitting
  real data. We introduce 4 new diagnostics in helioseismology: the
  (m,nu ) echelle diagram, the cross echelle diagram, the inter echelle
  diagram, and the cross spectrum ratio. These diagnostics are extremely
  powerful to visualize and understand the covariance matrices of the
  Fourier spectra, and also to find bugs in the data analysis code. The
  diagrams are used to verify the computation of the leakage matrices,
  and also to measure quantitatively these matrices. Cross spectrum ratios
  are used to obtain quantitative information on the noise covariance
  matrices. Numerous examples using the LOI/SOHO and GONG data are given.

---------------------------------------------------------
Title: The art of fitting p-mode spectra. I. Maximum likelihood
    estimation
Authors: Appourchaux, T.; Gizon, L.; Rabello-Soares, M. -C.
1998A&AS..132..107A    Altcode: 1997astro.ph.10082A
  In this article we present our state of the art of fitting helioseismic
  p-mode spectra. We give a step by step recipe for fitting the spectra:
  statistics of the spectra both for spatially unresolved and resolved
  data, the use of Maximum Likelihood estimates, the statistics of
  the p-mode parameters, the use of Monte-Carlo simulation and the
  significance of fitted parameters. The recipe is applied to synthetic
  low-resolution data, similar to those of the LOI, using Monte-Carlo
  simulations. For such spatially resolved data, the statistics of the
  Fourier spectrum is assumed to be a multi-normal distribution; the
  statistics of the power spectrum is not a chi (2) with 2 degrees of
  freedom. Results for l=1 shows that all parameters describing the p
  modes can be obtained with negligible bias and with minimum variance
  provided that the leakage matrix is known. Systematic errors due to
  an imperfect knowledge of the leakage matrix are derived for all the
  p-mode parameters.

---------------------------------------------------------
Title: Asymmetry and Frequencies of Low-Degree p-Modes and the
    Structure of the Sun's Core
Authors: Toutain, T.; Appourchaux, T.; Fröhlich, C.; Kosovichev,
   A. G.; Nigam, R.; Scherrer, P. H.
1998ApJ...506L.147T    Altcode:
  An accurate determination of the frequencies of low-degree solar
  p-modes is an important task of helioseismology. Using 679 days of
  solar oscillation data observed in Doppler velocity and continuum
  intensity from two Solar and Heliospheric Observatory instruments
  (the Michelson Doppler Imager and the SunPhotoMeter), we show that
  fitting the spectra with Lorentzian profiles leads to systematic
  differences between intensity and velocity frequencies as large as
  0.1 μHz for angular degrees l=0, 1, and 2 because of the opposite
  asymmetry between intensity and velocity. We use a physics-based
  asymmetrical line shape to fit p-mode lines, and we demonstrate
  that their asymmetry is statistically significant and that frequency
  differences are considerably reduced. These measurements provide more
  accurate estimates of the solar eigenfrequencies. We discuss inferences
  of the structure of the solar core.

---------------------------------------------------------
Title: Results from the Luminosity Oscillations Imager on board SOHO:
    Low-degree p-mode Parameters for a 2-year Data Set
Authors: Appourchaux, T.; Virgo Team
1998ESASP.418...99A    Altcode: 1998soho....6...99A
  I will report on the results from a 2-year LOI time series starting on
  March 27, 1995 and ending on March 26, 1998. From the data set, I have
  analysed independently two 1-year time series mainly for minimizing
  the effect of solar activity. For l &lt; 3 the p-mode data are fitted
  using the Fourier spectra taking into account the mode leakage and
  noise correlations (Appourchaux et al, 1998; Schou, 1992). For 4 &lt;
  l &lt; 9, the small number of pixels (12) lead to undersampling that
  result into non-inversible leakage matrices: the Fourier spectra cannot
  be utilised anymore (Appourchaux et al, 1998). In addition for these
  degrees, the spectra of the l = 4,5 modes are strongly polluted by the
  l = 7,8 modes, and vice versa. Due to these two major problems, I have
  fitted simultaneously the power spectra of l = 4,7 and l = 5,8; this is
  clearly an approximation that will lead to systematic errors. I will
  give tables of frequencies, splittings and linewidths for the 2-year
  data set. The splittings are compared with other data sets such as LOWL,
  MDI and GONG. The effects of the solar activity is also studied.

---------------------------------------------------------
Title: The art of fitting p-mode spectra
Authors: Appourchaux, T.; Gizon, L.
1998IAUS..185...43A    Altcode:
  We describe how to extract the p-mode parameters from complex Fourier
  spectra using maximum likelihood estimators. We expect our description
  to be quite general and didactic. We discuss problems such as the
  choice of the optimal filters and the construction of the leakage and
  covariance matrices. The LOI/SOHO Team makes use of these methods.

---------------------------------------------------------
Title: Sources of Amplitude Modulation of Solar P-Modes
Authors: Leifsen, Torben; Andersen, Bo; Appourchaux, Thierry
1998ESASP.418..939L    Altcode: 1998soho....6..939L
  We study the amplitude variation with time of the solar radial
  p-modes. Continuous datasets from more than two years of observations
  with the SOHO/VIRGO SPM and LOI instruments were used. A Hilbert
  transform method was used to study the time variation of the amplitudes
  of the l = 0-3 modes with radial order 12-32. The observed amplitudes of
  the modes vary substantially with time on a large range of timescales
  up to more than a solar rotation. As expected the power spectra of
  the amplitude variation show little or no consistent periodicities for
  most of the modes. However, for some of the modes, specifically for it
  l = 0, n = 21 and 22, a strong modulation is observed with the solar
  sidereal rotation frequency. This is a very surprising result as the
  {l} = 0 modes should be insensitive to the solar rotation. In contrast
  the SPM blue channel irradiance observations show a modulation with
  the solar synodic rotation frequency. This is as one would expect as
  active regions rotate over the solar disc and thereby modulate the
  irradiance signal. A comparison with MDI velocity data show that the
  amplitude modulation of the modes closely resembles the modulation as
  observed with VIRGO/SPM. This shows that the observed modulation is
  not an effect of the irradiance variation due to active regions, but
  rather a modulation of the mode itself by rotation. This conclusion is
  strengthened by the fact that the symmetric {l} = 0 modes are modulated
  by the sidereal and not the synodic rotation frequency. The two years
  of observations cover times of both low and higher solar activity as
  the activity of the new solar cycle started in the summer of 1997. In
  the solar irradiance one can see the onset of the new solar cycle
  as a frequency shift to lower frequencies as the activity appear at
  higher solar latitudes. Surprisingly a similar shift is also seen in
  the modulation of the two modes, indicating that the modulation of
  the modes is closely connected to the latitudes of solar activity.

---------------------------------------------------------
Title: Line Asymmetry of VIRGO and MDI Low-Degree p Modes
Authors: Toutain, T.; Appourchaux, T.; Frohlich, C.; Kosovichev, A.;
   Rakesh, N.; Scherrer, P.
1998ESASP.418..973T    Altcode: 1998soho....6..973T
  Using continuous time series of 610 days of velocity (MDI, LOI-proxy)
  and intensity (VIRGO, SPM and LOI) we show that Lorentzian profiles as
  a model of low-degree p-mode line leads to systematic differences in
  the determination of intensity and velocity mode frequencies. These
  differences, as large as 0.1 muHz for degrees l = 0, 1, 2 and 3,
  are frequency-dependent. The use of a physics-based asymmetrical line
  shape (Rakesh et al., 1998) to fit the same lines has allowed us to
  significantly reduce differences in the frequency determination. P-mode
  lines in velocity exhibit a significant negative asymmetry (excess
  of power in the left wing) whereas p-modes lines in intensity have a
  positive asymmetry (excess of power in the right wing). The magnitude
  and sign of this asymmetry are directly related to the location of
  the source of p-mode excitation and to the correlation between mode
  and solar noise.

---------------------------------------------------------
Title: Rotation of the Solar Core Inferred from GONG Data
Authors: Rabello-Soares, M. C.; Appourchaux, T.; Christensen-Dalsgaard,
   J.
1998ESASP.418..837R    Altcode: 1998soho....6..837R
  We present inferences of the solar core rotation derived from GONG
  frequency splittings. The GONG data for the low-degree modes (l &lt;=
  6) are for the one year period Aug. 1995-1996; these splittings
  were determined using a new method of fitting heliosismic spectra
  (Rabello-Soares &amp; Appourchaux 1998). These are combined with
  GONG data for higher degree modes, as obtained by the GONG team (Hill
  et al. 1996). We have employed a new two-dimensional implementation
  of the optimally localized averages (OLA) inversion method (Chaplin
  et al. 1998). As in one dimension, the OLA produces better-localized
  averaging kernels than do least-squares techniques. This is particularly
  beneficial in the deep interior, where it is in any case difficult to
  obtain localized information.

---------------------------------------------------------
Title: Time Dependence of Solar Noise Observed with VIRGO
Authors: Andersen, Bo; Leifsen, Torben; Appourchaux, Thierry; Frohlich,
   Claus; Jiménez, Antonio; Wehrli, Christoph
1998ESASP.418...83A    Altcode: 1998soho....6...83A
  The effect of non- and quasiperiodic solar surface structures dominate
  the power spectra of solar irradiance and radiance over a broad range
  of time scales. Only in the p-mode region above about 2 mHz and in the
  rotationally dominated region below about 3 μ Hz there seems to be
  narrow stationary peaks. The solar background signal, or solar noise has
  clear large scale quasi-stationary structures that seems to be closely
  correlated to the combination of timescales and contrasts of the solar
  surface sources. The dominant sources are the solar granulation and
  supergranulation. The solar noise determines the detection limit in
  the search for g-modes. Thus an increased understanding of it may be
  helpfull in this search. In addition this understanding will be usefull
  to determine the properities of stellar small scale surface structures
  from the data from future asteroseismology space missions. In this
  study we use the VIRGO data to study the time variation of the solar
  noise with timescales from about one day to about one year.

---------------------------------------------------------
Title: Statistical Properties of the Amplitude Modulation of Solar
    p-Modes
Authors: Andersen, Bo; Aarset, Magne; Leifsen, Torben; Appourchaux,
   Thierry; Frohlich, Claus; Hoeksema, J. T.; Jiménez, Antonio; Toutain,
   Thierry
1998ESASP.418..897A    Altcode: 1998soho....6..897A
  The low degree solar p-modes show amplitude modulation at all observable
  timescales. For some modes a large fraction of this modulation seems
  to be correlated to the solar rotation. For other modes there seems
  to be little or no deterministic component in the modulation. Only
  intermittent correlation between the modulation of different modes
  have been observed. This is to be expected if the excitation of modes
  is completely stochastic. None of the observational methods observe the
  modes directly. In different ways they all observe the solar atmospheres
  response to the modes. This implies that the modes may be modulated by
  this response. By studying the statistical properties of the different
  observed modes we attempt to discriminate between variations in the
  modes themselves and the atmospheric response. In this work we study the
  statistical properties of the mode amplitude variations for radial order
  p-modes observed with the VIRGO and SOI/MDI instruments on SOHO. The
  time scales studied span the region from 0.2 μ Hz to 15 muHz. Here,
  we are modelling the amplitude modulation, utilising the concepts of
  state space models, as a stochastic process and study the properties
  of this model as function of radial order and line width of the modes.

---------------------------------------------------------
Title: Observations of the latitudinal variation of the solar radiance
    of non-active regions of the sun.
Authors: Domingo, V.; Sanchez, L.; Appourchaux, T.; Andersen, B.
1998IAUS..185..111D    Altcode:
  The Luminosity Oscillations Imager (LOI) of the VIRGO experiment
  aboard SOHO provides continuous measurement of the solar irradiance
  in a 5 nm band around 500 nm. The solar image is broken down in 12
  pixels distributed in 4 latitudinal bands. The first year of operation
  of the instrument has taken place during a period of solar minimum
  activity. The measurements provide an indication of the distribution
  of the solar irradiance variations versus latitude. Contributions to
  the observed variations due to the presence of active regions are
  discussed in relation to the possible effect of the evolving solar
  cycle (structure of the convection zone): short term variations versus
  long term variations. The problem of the photometric stability of
  the measurements needed for the investigation is thoroughly treated
  by self consistency and by comparison with other instruments on SOHO
  (VIRGO sun- photometers and MDI intensity measurements).

---------------------------------------------------------
Title: LOI low-degree rotational splittings
Authors: Appourchaux, T.; Rabello Soares, M. C.; Gizon, L.
1998IAUS..185..167A    Altcode:
  We present measurements of rotational splitting frequencies of
  low-degree p-modes. The data which have been analyzed correspond to
  one-year spatially resolved observations obtained with the Luminosity
  Oscillation Imager onboard the SOHO spacecraft.

---------------------------------------------------------
Title: Observational Upper Limits for Low-Degree Solar g-modes
Authors: Fröhlich, C.; Finsterle, W.; Andersen, B.; Appourchaux, T.;
   Chaplin, W. J.; Elsworth, Y.; D. O. Gough; Hoeksema, J. T.; Isaak,
   G. R.; Kosovichev, A. G.; Provost, J.; Scherrer, P. H.; Sekii, T.;
   Toutain, T.
1998ESASP.418...67F    Altcode: 1998soho....6...67F
  No abstract at ADS

---------------------------------------------------------
Title: Amplitude modulation of radial p-modes from Virgo
Authors: Leifsen, T.; Andersen, B. N.; Appourchaux, T.; Frohlich,
   C.; Jimenez, A.; Toutain, T.; Wehrli, C.
1998IAUS..185..113L    Altcode:
  We present results from wavelet analysis of more than one year of
  data from the VIRGO Sun Photometers (SPM) and the VIRGO Luminosity
  Oscillation Imager (LOI) onboard the SOHO spacecraft. The temporal
  behaviour of p-modes with l=0--2 is presented. The analysis of
  the l=0 modes show a modulation of the mode amplitudes with the
  solar rotation. This result is quite surprising as the l=0 modes
  should not be sensitive to the solar rotation. Possible effects of
  varying solar activity on the modulation of the mode amplitudes is
  investigated. The effect of the modulation on the fitting of mode lines
  and determination of the mode frequencies is also studied. Wavelet
  analysis has a fundamental limitation in the ability to achieve
  simultaneous high frequency and time resolution. In order to be able
  to study the rotationally split components of the l=1 modes with good
  time resolution, we apply a spatial filtering technique on the LOI
  data to separate the different components.

---------------------------------------------------------
Title: A comparison of low-degree solar p-mode frquencies from BISON
    and LOI
Authors: Appourchaux, T.; Chaplin, W. J.; Elsworth, Y.; Isaak, G. R.;
   McLeod, C. P.; Miller, B. A.; New, R.
1998IAUS..185...45A    Altcode:
  Here, we compare the low-degree solar p-mode frequencies returned from
  the analysis of two, contemporaneous, independent helioseismological
  data sets collected during 1996. The first comprises Doppler velocity
  observations of the 770-nm line of potassium, made in integrated
  sunlight by the six-station, terrestrial Birmingham Solar-Oscillations
  Network (BiSON). The second consists of irradiance distribution
  measurements of the solar disc, made at 500rm nm, by the Luminosity
  Oscillations Imager (LOI), which is part of the VIRGO experiment on
  the ESA/NASA SOHO satellite.

---------------------------------------------------------
Title: LOI/SOHO constraints on oblique rotation of the solar core
Authors: Gizon, L.; Appourchaux, T.; Gough, D. O.
1998IAUS..185...37G    Altcode:
  The Sun is usually assumed to rotate about a single axis, tilted with
  respect to the ecliptic normal by an angle of 7.25 degrees. Although
  we have an excellent knowledge of the direction of the rotation axis of
  the photospheric layers, we cannot exclude a priori that the direction
  of the rotation axis could vary as a function of radius. We have tried
  to check whether the assumption of rotation about a unique axis is
  consistent with helioseismic data. We report on an attempt to measure
  the directions of the pulsation axes of several low-degree modes of
  oscillation in the LOI/SOHO Fourier spectra.

---------------------------------------------------------
Title: The Structure of the Solar Core: an Observer's Point of View
Authors: Appourchaux, T.
1998ESASP.418...37A    Altcode: 1998soho....6...37A
  Since the beginning of helioseismology, most of the internal and
  dynamics structure of the Sun has been revealed or so we thought. The
  last island where our powerful tools start to fail is the solar core,
  where nuclear reactions take place. With the advent of SOHO and GONG,
  we have now a quality of helioseismic data without precedence that
  should enable us to understand better the physics of the deepest solar
  regions. This goal can be partially achieved by measuring low-degree
  rotational splitting of p-modes, and by detecting the elusive
  g-modes. In a first part, I will review the fitting techniques that
  are being used for inferring the rotational splittings of low-degree
  p-modes. I will particularly focus on Fourier spectra fitting developped
  by Schou (1992) and refined by Appourchaux et al (1998). I will show
  how one can visualize from the data, the leakage matrix and how one
  can clean the data from the mode leakages. I will give examples of
  systematic errors introduced by the leakage matrix and by modes of
  aliasing degrees. I will also compare the Fourier spectra fitting
  technique to others techniques that use power spectra. I will give some
  recent results from SOHO and GONG. In a second part, I will report on
  the progress of the Phoebus group for detecting g-modes. The Phoebus
  group is composed of team members of BiSON, VIRGO and SOI/MDI. I will
  summarize some of the techniques we used for finding g-modes, and how
  one can use those for finding low-order low-frequency p-modes. I will,
  most probably, not report on g-mode detection but most likely stress
  that the future ahead of us is brighter than ever.

---------------------------------------------------------
Title: Comparative Studies of Low-Order and Low-Degree Solar p Modes
Authors: Appourchaux, T.; Andersen, B.; Chaplin, W.; Elsworth, Y.;
   Finsterle, W.; Frohlich, C.; Gough, D.; Hoeksema, J. T.; Isaak, G.;
   Kosovichev, A.; Provost, J.; Scherrer, P.; Sekii, T.; Toutain, T.
1998ESASP.418...95A    Altcode: 1998soho....6...95A
  The amplitudes of solar p-modes decrease steeply with decreasing
  radial order below about 17. The background solar signal (solar noise)
  in general increases steadily with decreasing frequency. For the
  irradiance and radiance measurements with VIRGO or SOI/MDI on SOHO this
  combination makes it difficult to detect low degree modes below about
  1.8 mHz. The solar noise as observed in velocity with SOI/MDI or the
  ground based BISON network is significantly lower in this region than
  in intensity measurements. This allows low degree modes to be observed
  close to 1 mHz. We present results of detection and charaterization
  of the lowest order observable p-modes both in velocity and intensity
  measurements. Where applicable the properties of the modes observed
  with the two methods are compared.

---------------------------------------------------------
Title: The Effect of Amplitude Modulation on Asymmetries of Solar
    p-Modes
Authors: Andersen, Bo; Leifsen, Torben; Appourchaux, Thierry; Frohlich,
   Claus; Hoeksema, J. T.; Toutain, Thierry
1998ESASP.418..893A    Altcode: 1998soho....6..893A
  The low degree solar p-modes show an asymmetry in their line profiles
  that both depend on the observational technique and on the radial
  order of the modes. Typically the modes determined from observations
  with Doppler shift methods show an asymmetry towards lower frequency
  while the opposite is the case for modes determined from irradiance and
  radiance observations. The difference in asymmetry is probably caused by
  near surface effects. If the modes are fitted with symmetric functions
  this leads to a systematic shift in the frequency determinations for
  the two data sets. This may lead to systematic differences in the
  inversions based on the different frequencies. All the mode amplitudes
  show significant time variation. The typical centroid frequency also
  varies with timescales from a few days to the solar cycle. These
  variations may set absolute limits to the observable accuracy of the
  frequency determination. These time modulations may influence the
  observed line profiles and thus the frequency determinations. Here we
  present results of the effect on the mode asymmetry of the amplitude
  modulation of low degree modes observed with VIRGO and SOI/MDI. The
  range in timescales is from a few days to a few solar rotations.

---------------------------------------------------------
Title: Measurement of GONG Low-Degree p-Mode Parameters
Authors: Rabello-Soares, M. C.; Appourchaux, T.
1998ESASP.418..299R    Altcode: 1998soho....6..299R
  Low-degree solar p modes observed by the GONG network have been analysed
  for ell &lt;= 6 yielding accurate measurements of their frequencies,
  splittings and linewidths. The results obtained show significant
  improvement over the GONG project parameters especially for minimizing
  the bias on the splitting and the error bars. We used a new method
  of fitting helioseismic spectra where, instead of fitting the power
  spectra, we fitted the Fourier spectra involving the knowledge of the
  mode leakage matrix. The effect of an imperfect knowledge of the ell =
  1 leakage matrix upon the splitting determination is shown both for
  power spectra and Fourier spectra fitting. In addition, the effect of
  the leakage between the modes of different degrees, or spatial alias,
  upon the splitting coefficient is analysed. A procedure for cleaning
  the spatial alias is described leading to splitting coefficients with
  smaller systematic errors than before.

---------------------------------------------------------
Title: On the Effect of Active Regions on the Solar Irradiance
Authors: Domingo, V.; Sanchez, L.; Appourchaux, T.; Fröhlich, C.;
   Wehrli, C.; Crommelynck, D.; Pap, J.
1997ESASP.415..469D    Altcode: 1997cpsh.conf..469D
  No abstract at ADS

---------------------------------------------------------
Title: Successful Recovery from LOI Cover In-Orbit Anomaly on SOHO
Authors: Yorck, M.; Appourchaux, T.; Eiden, M.
1997ESASP.410..215Y    Altcode: 1997smt..conf..215Y
  No abstract at ADS

---------------------------------------------------------
Title: Tri-Phonic Helioseismology: Comparison of Solar P Modes
    Observed by the Helioseismology Instruments Aboard SOHO
Authors: Toutain, T.; Appourchaux, T.; Baudin, F.; Fröhlich, C.;
   Gabriel, A.; Scherrer, P.; Andersen, B. N.; Bogart, R.; Bush, R.;
   Finsterle, W.; García, R. A.; Grec, G.; Henney, C. J.; Hoeksema,
   J. T.; Jiménez, A.; Kosovichev, A.; Roca Cortés, T.; Turck-Chièze,
   S.; Ulrich, R.; Wehrli, C.
1997SoPh..175..311T    Altcode:
  The three helioseismology instruments aboard SOHO observe solar p modes
  in velocity (GOLF and MDI) and in intensity (VIRGO and MDI). Time series
  of two months duration are compared and confirm that the instruments
  indeed observe the same Sun to a high degree of precision. Power
  spectra of 108 days are compared showing systematic differences between
  mode frequencies measured in intensity and in velocity. Data coverage
  exceeds 97% for all the instruments during this interval. The weighted
  mean differences (V-I) are −0.1 µHz for l=0, and −0.16 µHz for
  l=1. The source of this systematic difference may be due to an asymmetry
  effect that is stronger for modes seen in intensity. Wavelet analysis
  is also used to compare the shape of the forcing functions. In these
  data sets nearly all of the variations in mode amplitude are of solar
  origin. Some implications for structure inversions are discussed.

---------------------------------------------------------
Title: On the direction of the rotation axis of the Sun
Authors: Gizon, L.; Appourchaux, T.
1997BAAS...29R1121G    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Contribution of Low-l p Modes to the Solar Equatorial Rotation
    Profile
Authors: Rabello Soares, M. C.; Roca Cortés, T.; Jiménez, A.;
   Appourchaux, T.; Eff-Darwich, A.
1997ApJ...480..840R    Altcode:
  The solar equatorial velocity profile is known down to the base of the
  convection zone with high precision (&lt;=1%) from here downward until
  approximately 0.5 R<SUB>⊙</SUB>, it seems to be constant, independent
  of latitude, and lower than the equatorial surface rate. This result
  comes from the inversion of high-l p-mode observations (Thompson
  et al. 1996), while low-l p modes, which penetrate deeper, are not
  measured to the precision required. Recently, new results from the
  LOWL instrument on such modes suggest that deeper down, the rotation
  rate could be even slower (Tomczyk, Schou, &amp; Thompson 1995a). Here
  results from LOI-T, a low-resolution high-precision photometer, are
  presented and analyzed to yield accurate measurements of the frequencies
  and splittings of modes with 2 &lt;= l &lt;= 8. The accuracy of the
  frequency determinations and the agreement with the best results
  yielded by low- and high-l instruments give credit to the results and
  show its capability as an intercalibrating tool for experiment. The
  splittings found, combined with those of GONG (high-l modes), are
  used to perform an inversion of the equatorial rotation profile in the
  radiative interior; the result found is that the region from 0.2 &lt;=
  r/R<SUB>⊙</SUB> &lt;= 0.4 rotates slower than the surface rate.

---------------------------------------------------------
Title: Study of the Effect of Active Regions on the Solar Irradiance
    During Solar Minimum
Authors: Domingo, V.; Sanchez, L.; Appourchaux, T.; Froehlich, C.;
   Wehrli, C.; Hoeksema, T.; Pap, J.
1997SPD....28.0206D    Altcode: 1997BAAS...29..893D
  We have determined both the size of the area that contributes to the
  solar irradiance increase around an active region and the angular
  distribution of the radiance excess in it, using data obtained during
  about one year around solar minimum (April 1996 - April 1997). During
  the solar minimum and the early raising phase of the new maximum it
  is possible to study the effect of isolated active regions while there
  are few of them. The result of this study will be important to separate
  the contribution of the active regions to the solar irradiance change
  during the solar cycle from any underlying long term effect, if there
  is one. The solar radiance measured by the Low-resolution Oscillations
  Imager (LOI) of the VIRGO instrument and by the MDI instrument aboard
  SOHO is used to determine the dimension of the radiating area. The
  increase in irradance is determined by the Sun Photometers (SPM)
  and Radiometers on the VIRGO instrument.

---------------------------------------------------------
Title: The Effects of Systematic Errors in the Estimation of p-Mode
    Frequencies on the Inversion of Solar Internal Structure
Authors: Rhodes, E. J., Jr.; Appourchaux, T.; Bachmann, K.; Kosovichev,
   A. G.; Scherrer, P. H.; Schou, J.; Reiter, J.
1997SPD....28.0901R    Altcode: 1997BAAS...29..913R
  The frequencies and associated uncertainties of the low-, intermdeiate-,
  and high-degree p-mode oscillations are the input quantities for the
  inversion programs which infer the thermodynamic structure of the solar
  interior. In this review we will attempt to demonstrate the different
  possible systematic errors that are currently present in our estimation
  of both the modal frequencies and their uncertainties. We will also
  demonstrate the effects of some of these errors upon the inferred
  radial profile of the solar internal sound speed. Among the different
  possible systematic errors which we will discuss are the effects of:
  1)the asymmetric shapes of the peaks in observational power spectra,
  2)the realization noise which is present in the case of the low-degree
  modes, 3)the different frequency estimation methods used on different
  types of power spectra (i.e., on either tesseral power spectra or
  on m-averaged power spectra), 4) the differences in the frequencies
  which are estimated from velocity- and intensity-based power spectra,
  5) the blending of individual p-modes into so-called "ridges" of
  observed power at both high degrees and high frequencies, and 6) the
  spatial and temporal aliasing which occurs at both high degrees and
  at high frequencies. We will demonstrate these different errors using
  results obtained with the VIRGO and MDI experiments onboard the SOHO
  spacecraft. We will also compare some of these space-based results
  with the results of similar estimates obtained from co-temporaneous
  ground-based observations, such as from the Mt. Wilson 60-Foot Solar
  Tower. We will include the results from different structural inversions
  carried out with different sets of input frequencies and uncertainties
  in order to demonstrate the effects of these different systematic
  errors upon the inverted internal sound speed profile.

---------------------------------------------------------
Title: An estimate of the solar background irradiance power spectrum.
Authors: Rabello-Soares, M. C.; Roca Cortes, T.; Jimenez, A.; Andersen,
   B. N.; Appourchaux, T.
1997A&A...318..970R    Altcode:
  Knowledge of the solar irradiance background is of great importance
  to solar and stellar physics. In particular, its contribution
  to the solar oscillations power spectrum is highly relevant as it
  represents the ultimate limit to the sensitivity of solar oscillations'
  observations. An analysis of the power spectra of the solar photometric
  data coming from four different instruments - two space-borne (ACRIM
  and IPHIR) and two earth-based instruments (SLOT and LOI-T) - has
  been performed to obtain the upper limit to the solar irradiance
  background's spectrum. These observations have been compared to a
  numerical model computed for the non-coherent solar surface phenomena,
  namely granulation, mesogranulation and supergranulation. There is an
  overall good agreement between the general trend of the model and the
  observed data.

---------------------------------------------------------
Title: First results from VIRGO on SoHO
Authors: Frohlich, C.; Andersen, B. N.; Appourchaux, T.; Berthomieu,
   G.; Crommelynck, D. A.; Domingo, V.; Fichot, A.; Finsterle, W.;
   Gómez, M. F.; Gough, D.; Jiménez, A.; Leifsen, T.; Lombaerts, M.;
   Pap, J. M.; Provost, J.; Roca Cortés, T.; Romero, J.; Roth, H. -J.;
   Sekii, T.; Telljohann, U.; Toutain, T.; Wehrli, C.
1997IAUS..181...67F    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: In-Flight Performance of the Virgo Luminosity Oscillations
    Imager Aboard SOHO
Authors: Appourchaux, Thierry; Andersen, Bo N.; Fröhlich, Claus;
   Jiménez, Antonio; Telljohann, Udo; Wehrli, Christoph
1997SoPh..170...27A    Altcode:
  The Luminosity Oscillations Imager (LOI) is a part of the VIRGO
  instrument aboard the Solar and Heliospheric Observatory (SOHO). The
  scientific objective of the LOI experiment is to identify and
  characterize pressure and internal gravity oscillations of the Sun by
  observing the radiance variations. The LOI is a low-resolution imager
  with 12 pixels, for the measurement of the radiance distribution
  over the solar disk at 500 nm. The low resolution capability of the
  instrument allows the identification of individual azimuthal orders
  for l = 0 to 7, without suffering the mixing that affects integrated
  solar disk instruments. The performance, calibrations and instrumental
  effects of the LOI are described together with the procedures for
  extracting the solar p modes.

---------------------------------------------------------
Title: First Results from VIRGO, the Experiment for Helioseismology
    and Solar Irradiance Monitoring on SOHO
Authors: Fröhlich, Claus; Andersen, Bo N.; Appourchaux, Thierry;
   Berthomieu, Gabrielle; Crommelynck, Dominique A.; Domingo, Vicente;
   Fichot, Alain; Finsterle, Wolfgang; Gómez, Maria F.; Gough, Douglas;
   Jiménez, Antonio; Leifsen, Torben; Lombaerts, Marc; Pap, Judit M.;
   Provost, Janine; Roca Cortés, Teodoro; Romero, José; Roth, Hansjörg;
   Sekii, Takashi; Telljohann, Udo; Toutain, Thierry; Wehrli, Christoph
1997SoPh..170....1F    Altcode:
  First results from the VIRGO experiment (Variability of solar IRradiance
  and Gravity Oscillations) on the ESA/NASA Mission SOHO (Solar and
  Heliospheric Observatory) are reported. The observations started
  mid-January 1996 for the radiometers and sunphotometers and near the
  end of March for the luminosity oscillation imager. The performance of
  all the instruments is very good, and the time series of the first 4-6
  months are evaluated in terms of solar irradiance variability, solar
  background noise characteristics and p-mode oscillations. The solar
  irradiance is modulated by the passage of active regions across the
  disk, but not all of the modulation is straightforwardly explained in
  terms of sunspot flux blocking and facular enhancement. Helioseismic
  inversions of the observed p-mode frequencies are more-or-less in
  agreement with the latest standard solar models. The comparison of
  VIRGO results with earlier ones shows evidence that magnetic activity
  plays a significant role in the dynamics of the oscillations beyond
  its modulation of the resonant frequencies. Moreover, by comparing
  the amplitudes of different components ofp -mode multiplets, each of
  which are influenced differently by spatial inhomogeneity, we have
  found that activity enhances excitation.

---------------------------------------------------------
Title: VIRGO: Experiment for Helioseismology and Solar Irradiance
    Monitoring
Authors: Fröhlich, Claus; Romero, José; Roth, Hansjörg; Wehrli,
   Christoph; Andersen, Bo N.; Appourchaux, Thierry; Domingo, Vicente;
   Telljohann, Udo; Berthomieu, Gabrielle; Delache, Philippe; Provost,
   Janine; Toutain, Thierry; Crommelynck, Dominique A.; Chevalier,
   André; Fichot, Alain; Däppen, Werner; Gough, Douglas; Hoeksema,
   Todd; Jiménez, Antonio; Gómez, Maria F.; Herreros, José M.; Cortés,
   Teodoro Roca; Jones, Andrew R.; Pap, Judit M.; Willson, Richard C.
1995SoPh..162..101F    Altcode:
  The scientific objective of the VIRGO experiment (Variability of solar
  IRradiance and Gravity Oscillations) is to determine the characteristics
  of pressure and internal gravity oscillations by observing irradiance
  and radiance variations, to measure the solar total and spectral
  irradiance and to quantify their variability over periods of days to
  the duration of the mission. With these data helioseismological methods
  can be used to probe the solar interior. Certain characteristics of
  convection and its interaction with magnetic fields, related to, for
  example, activity, will be studied from the results of the irradiance
  monitoring and from the comparison of amplitudes and phases of the
  oscillations as manifest in brightness from VIRGO, in velocity from
  GOLF, and in both velocity and continuum intensity from SOI/MDI. The
  VIRGO experiment contains two different active-cavity radiometers for
  monitoring the solar `constant', two three-channel sunphotometers (SPM)
  for the measurement of the spectral irradiance at 402, 500 and 862 nm,
  and a low-resolution imager (LOI) with 12 pixels, for the measurement
  of the radiance distribution over the solar disk at 500 um. In this
  paper the scientific objectives of VIRGO are presented, the instruments
  and the data acquisition and control system are described in detail,
  and their measured performance is given.

---------------------------------------------------------
Title: An Attempt to Estimate the Intensity Background Spectra
Authors: Rabello Soares, M. C.; Roca Cortés, T.; Jiménez, A.;
   Appourchaux, T.
1995ESASP.376b.397R    Altcode: 1995help.confP.397R; 1995soho....2..397R
  No abstract at ADS

---------------------------------------------------------
Title: The Luminosity Oscillations Imager on Board Virgo: Design
    and Performances
Authors: Appourchaux, T.; Telljohann, U.; Martin, D.; Fleur, J.;
   Lévêque, S.
1995ESASP.376b.359A    Altcode: 1995soho....2..359A; 1995help.confP.359A
  No abstract at ADS

---------------------------------------------------------
Title: Results from the Luminosity Oscillations Imager
Authors: Appourchaux, T.; Toutain, T.; Jiménez, A.; Rabello Soares,
   M. C.; Andersen, B. N.; Jones, A. R.
1995ESASP.376b.265A    Altcode: 1995help.confP.265A; 1995soho....2..265A
  No abstract at ADS

---------------------------------------------------------
Title: Preliminary Analysis of the Radius Signal on Loi-T
Authors: Rabello-Soares, M. C.; Appourchaux, T.; Jiménez, A.; Roca
   Cortés, T.
1995ESASP.376b.365R    Altcode: 1995help.confP.365R; 1995soho....2..365R
  No abstract at ADS

---------------------------------------------------------
Title: Solar P-Mode Frequencies from the IRIS Network
Authors: Gelly, B.; Fossat, E.; Palle, P.; Appourchaux, T.;
   Eghamberdiev, S.; Fierry-Fraillon, D.; Grec, G.; Hoeksema, J. T.;
   Khalikov, S.; Lazrek, M.; Loudagh, S.; Pantel, A.; Regulo, C.; Sanchez,
   L.; Schmider, F. X.
1995ESASP.376b.373G    Altcode: 1995help.confP.373G; 1995soho....2..373G
  No abstract at ADS

---------------------------------------------------------
Title: Frequencies and splittings of low-degree solar P modes:
    results of the Luminosity Oscillations Imager.
Authors: Appourchaux, T.; Toutain, T.; Telljohann, U.; Jimenez, A.;
   Rabello-Soares, M. C.; Andersen, B. N.; Jones, A. R.
1995A&A...294L..13A    Altcode:
  The Luminosity Oscillations Imager is a part of the VIRGO instrument
  to be flown aboard the Solar and Heliospheric Observatory in mid
  1995. Using a ground-based version of the instrument, we have detected
  low-l modes with a time series spanning 163 days. The low resolution
  capability of the instrument allows the identification of individual
  tesseral orders for l=2 to 5. The data reduction method prevents from
  observing the l=0 modes, and reduces the amplitude of the l=1 modes with
  m=+/-1. The frequencies and, for the first time, the linear component
  of the mode splitting (a_1_) are given for l=2 to 5 for each order
  n. The frequencies and the a_1_ are obtained by fitting simultaneously
  the 2l+1 spectra using maximum likelihood estimators. The splittings
  are compared with other published values.

---------------------------------------------------------
Title: STARS: A Proposal for a Dedicated Space Mission to Study
    Stellar Structure and Evolution
Authors: Fridlund, M.; Gough, D. O.; Jones, A.; Appourchaux, T.;
   Badiali, M.; Catala, C.; Frandsen, S.; Grec, G.; Roca Cortes, T.;
   Schrijver, K.
1995ASPC...76..416F    Altcode: 1995gong.conf..416F
  No abstract at ADS

---------------------------------------------------------
Title: Testing the Statistical Significance of the Asymmetries of
p-Mode Line Profiles: Application to the IPHIR Data
Authors: Appourchaux, T.; Toutain, T.; Gough, D. O.; Kosovichev, A.
1995ASPC...76..314A    Altcode: 1995gong.conf..314A
  No abstract at ADS

---------------------------------------------------------
Title: VIRGO - the Solar Monitor Experiment on SOHO
Authors: Appourchaux, T.; Domingo, V.; Frohlich, C.; Romero, J.;
   Wehrli, C.; Andersen, B. N.; Berthomieu, G.; Delache, P.; Crommelynck,
   D.; Jimenez, A.; Roca Cortes, T.; Jones, A. R.
1995ASPC...76..408A    Altcode: 1995gong.conf..408A
  No abstract at ADS

---------------------------------------------------------
Title: Frequencies and splittings of low-degree solar p modes:
    Results of the Luminosity Oscillations Imager
Authors: Appourchaux, T.
1995HiA....10..336A    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Maximum likelihood estimators: an application to the estimation
    of the precision of helioseismic measurements.
Authors: Toutain, T.; Appourchaux, T.
1994A&A...289..649T    Altcode:
  In this paper we apply the theory of Maximum Likelihood estimators to
  determine the precision of parameters in fitting Lorentzian profiles
  to helioseismic power spectra. The precision of frequency, linewidth,
  amplitude and noise determination for a single p mode, and of the l=1
  splitting, are derived as a function of the signal-to-noise ratio
  and the spectral resolution of the spectrum. Libbrecht's formula
  (Libbrecht 1992) for frequency precision is derived in a more general
  case. For validating the approach, the theoretical precisions are
  compared with those obtained with Monte-Carlo simulations and with
  IPHIR observations. The robustness of the precisions obtained is ideal
  for predictive purposes. The method used to derive the precisions is
  general enough so that it can be used for others purposes.

---------------------------------------------------------
Title: STARS - an investigation of stellar structure and evolution.
Authors: Fridlund, M.; Appourchaux, T.; Pace, O.; Volunte, S.
1994ESAJ...18..247F    Altcode:
  STARS is a mission targeted at the understanding of stellar physics,
  by carrying the established technique of helioseismology into the
  new field of asteroseismology. This requires the measurement of
  the miniscule variations in the light output of a stellar object
  that result when acoustical waves hit the outer boundary of its
  surface. These waves penetrate to the very center of the object and
  thus carry information about the interior. In order to detect these
  variations, STARS will have to carry the measuring of stellar flux to
  new limits. Intimately coupled to the properties of the stellar interior
  is the surface activity. A second part of the STARS experiment focuses
  on time-resolved observations of this activity, providing information
  about the outer boundary of the star, stellar rotation and angular
  momentum transport, as well as magnetic and chromospheric acitivity.

---------------------------------------------------------
Title: PRISMA - Probing Rotation and Interior of Stars:
    Microvariability and Activity. Report on the phase A study.
Authors: Appourchaux, T.
1993pris.book.....A    Altcode:
  The PRISMA mission addresses one of the most fundamental areas of
  astronomy: the structure and evolution of the stars. It uses the new
  technique of asteroseismology, measuring the surface amplitude of
  oscillations which penetrate deep into the interior of stars, whilst
  simultaneously monitoring surface activity.

---------------------------------------------------------
Title: Prisma - the First Space Mission to See Inside the Stars
Authors: Appourchaux, T.; Gough, D. O.; Catala, C.; Frandsen, S.;
   Frohlich, C.; Hoyng, P.; Jones, A.; Lemaire, P.; Tondello, G.; Weiss,
   W. W.
1993ASPC...42..411A    Altcode: 1993gong.conf..411A
  No abstract at ADS

---------------------------------------------------------
Title: Stellar seismology and activity: the need to go to space
    (PRISMA) (invited paper)
Authors: Appourchaux, T.; Catala, C.; Catalano, S.; Frandsen, S.;
   Jones, A.; Lemaire, P.; Weiss, W. W.
1993MmSAI..64..415A    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: PRISMA. Probing Rotation and Interior of Stars:
    Microvariability and activity
Authors: Appourchaux, T.; Catala, C.; Cornelisse, J.
1993ppri.book.....A    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: PRISMA - the first space mission to see inside the stars.
Authors: Appourchaux, T.; Fridlund, M.; Cornelisse, J.; Volonté, S.
1993ESAJ...17..239A    Altcode:
  The PRISMA - Probing Rotation and Interior of Stars: Microvariability
  and Activity - mission addresses one of the most fundamental areas
  of astronomy: the structure and evolution of stars. It uses the new
  technique of asteroseismology, measuring the surface manifestation of
  oscillations that penetrate deep into the interiors of stars, whilst
  simultaneously monitoring surface activity.

---------------------------------------------------------
Title: PRISMA: Probing Stars from Core to Corona
Authors: Appourchaux, T.; Catala, C.; Catalano, S.; Fransden, S.;
   Fröhlich, C.; Gough, D. O.; Hoyng, P.; Jones, A.; Lemaire, P.;
   Tondello, G.; Weiss, W.
1993ASSL..183..505A    Altcode: 1993pssc.symp..505A
  No abstract at ADS

---------------------------------------------------------
Title: PRISMA: a new space mission for stellar physics.
Authors: Appourchaux, T.; Gough, D.; Hyoyng, P.; Catala, C.; Frandsen,
   S.; Froehlich, C.; Jones, A.; Lemaire, P.; Tondello, G.; Weiss, W. W.
1993ASPC...40..812A    Altcode: 1993ist..proc..812A; 1993IAUCo.137..812A
  This paper mainly focuses on the scientific objectives that can be
  achieved with a new space mission of the European Space Agency -
  PRISMA (Probing Rotation and Interior of Stars: Microvariability
  and Activity). The scientific objectives can be classified into
  three areas of interest: (1) Stellar structure and evolution. (2)
  Stellar atmospheres and magnetic fields. (3) Stellar dynamics and
  stellar dynamos.

---------------------------------------------------------
Title: Passive thermal control of a multilayer filter for space-based
    solar observations.
Authors: Appourchaux, Thierry; Cislaghi, Massimo
1992OptEn..31.1715A    Altcode:
  Temperature distributions inside multilayer filters are often
  required to assess performance. This subject is rarely treated in the
  literature. Guidelines were developed that can be used to calculate a
  thermal model for various applications. In this study the guidelines
  are applied to an optical filter. This filter, which is not actively
  thermally controlled, is the front element in a space experiment
  devoted to the observation of solar intensity fluctuations. Temperature
  distributions were calculated for different designs. The final design
  minimizes temperature gradients, as well as degradation effects due to
  UV and particle radiation. The effect of space exposure on temperature
  distributions inside the filter is also addressed.

---------------------------------------------------------
Title: ESA's report to the 29th COSPAR Meeting
Authors: Appourchaux, T.; Chicarro, A.; Domingo, V.; Fridlund, M.;
   Huber, M.; Innocenti, L.; Jakobsen, P.; Kessler, M.; Lebreton, J. P.;
   Parmar, A.
1992wadc.meet.....A    Altcode:
  All ESA missions in operation, under development, or in planning are
  described. Missions beyond the operational phase are also presented
  if considerable effort is still being expended in supporting the data
  analysis through an archive. The aging and completed missions are:
  IUE, Exosat, Hipparcos, Giotto extended mission, Ulysses, and Hubble
  Space Telescope. The projects under development are: Infrared Space
  Observatory (ISO), the Solar Terrestrial Science Program (STSP) (which
  comprises the four Cluster spacecraft and the Solar and Heliospheric
  Observatory (SOHO)), the X-ray Multimirror Mission (XMM) and the
  Cassini/Huygens mission. Missions under study are: the Far Infrared
  Space Telescope (FIRST), the comet nucleus sample return (Rosetta),
  the International Gamma Ray Laboratory (INTEGRAL), a network of three
  semi hard landers to be placed on the Martian surface (MARSNET), a
  mission for probing the interior and rotation of stars (PRISMA), and
  a Satellite Test of the Equivalence Principle (STEP). Missions beyond
  Horizon 2000 are: Return to the Moon, interferometry from space, and
  Vulcan. ESA platforms described are Eureca (the European retrieval
  carrier) and Simuris (a solar system and stellar interferometric
  mission for ultrahigh resolution imaging and spectroscopy).

---------------------------------------------------------
Title: PRISMA: A Space Facility for Studying the Rotation; Interior
    of Stars
Authors: Lemaire, P.; Appourchaux, T.; Jones, A.; Catala, C.; Catalano,
   S.; Frandsen, S.; Weiss, W.
1992ASPC...26..643L    Altcode: 1992csss....7..643L
  No abstract at ADS

---------------------------------------------------------
Title: Prisma - a Space Facility for Studying Rotation and Activity
Authors: Lemaire, P.; Appourchaux, T.; Catala, C.; Catalano, S.;
   Frandsen, S.; Jones, A.; Weiss, W.
1991ASIC..340..397L    Altcode: 1991amey.conf..397L
  No abstract at ADS

---------------------------------------------------------
Title: PRISMA: Probing Rotation and Interior of
    Stars. Microvariability and activity
Authors: Appourchaux, T.; Catala, C.; Catalano, S.
1991ppri.book.....A    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Prisma-probing rotation and interior of stars: Microvariability
    and activity
Authors: Lemaire, P.; Appourchaux, T.; Catala, C.; Catalano, S.;
   Frandsen, S.; Jones, A.; Weiss, W.
1991AdSpR..11d.141L    Altcode: 1991AdSpR..11..141L
  The measurement of frequencies, amplitudes and lifetimes of solar
  oscillations has proven to be a very powerful tool to sound the
  properties of the solar internal structure. Combined with observations
  of emerging solar magnetic field parameters of the solar internal
  structure and dynamo can be inferred. The same techniques may be
  used to sound stellar interiors: asteroseismology and observation
  of magnetic activity (emerging magnetic fields). The observation of
  photometric fluctuations down to micromagnitudes on stars along or
  near the main sequence when complemented with measurements of activity
  levels will provide a wealth of information on the internal structure
  and rotation rates, and its evolutions with age. The PRISMA mission
  is an ESA Assessment Study currently underway. We present here the
  scientific objectives of the mission, the measurements to be made, the
  techniques to be used, and the main characteristics of a model payload.

---------------------------------------------------------
Title: Observations of Low-Degree Solar Oscillations with Few
    Detector Elements
Authors: Appourchaux, T.; Andersen, B. N.
1990SoPh..128...91A    Altcode: 1990IAUCo.121P..91A
  The detection of low-degree solar oscillation modes with a specific
  low-resolution detector configuration is investigated. The detector is
  part of an instrument (the Luminosity Oscillations Imager) in the VIRGO
  package, to be flown on SOHO. Various problems such as p- and g-mode
  sensitivity, B and roll angle effects, modes isolation, cross-talk and
  guiding effects are treated for a given detector configuration. The
  computed sensitivity will enable the instrument to detect any type of
  modes for l &lt; 6.B and roll angle effects can be compensated by using
  adequate filters for mode isolation. Guiding effects are small for
  p-modes. Also some other complex high-degree mode effects are treated.

---------------------------------------------------------
Title: ESA's report to the 28th COSPAR meeting, The Hague
    (Netherlands), Jun 1990.
Authors: Appourchaux, T.; Burke, W. R.
1990ert..book.....A    Altcode:
  This report, presented to COSPAR's biennial meeting, covers
  the period May 1989 to April 1990. It describes all missions in
  the planning stage and under development, as well as missions in
  operation. Missions beyond the operational phase are also presented,
  if considerable effort is still being expended on establishing data
  bases or on data analysis. Contents: 1. Introduction. 2. On-going
  &amp; completed missions: IUE, Exosat, Hipparcos, Giotto extended
  mission. 3. Projects under development: Ulysses, Hubble Space Telescope,
  ISO, STSP (The Solar-Terrestrial Science Programme), Cassini/Huygens,
  XMM. 4. Missions under study: Cornerstone missions (FIRST, Rosetta),
  assessment studies, Third Millenium missions (Mars exploration,
  interferometry from space, Vulcan). 5. Platforms: Eureca A, Columbus
  Polar Platform. 6. Bibliography.

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Title: Optimization of parameters for helioseismology experiments
    measuring solar radial velocities
Authors: Appourchaux, T.
1989A&A...222..361A    Altcode:
  Solar-oscillation instruments have many common characteristics,
  such as detecting solar radial velocities on Fraunhofer lines with a
  2-point measuring technique, high spectral resolution and stability,
  etc. The 2-point measuring technique is described including spectral
  responses of filter and blocker, calibration, sensitivity and photon
  noise. Optimization of different parameters such as filter profile,
  filter bandwidth, filter scanning range, line profile, line depth and
  prefilter bandwidth is addressed by means of a simple model. This
  analysis is then applied to existing or future helioseismology
  instruments.

---------------------------------------------------------
Title: The stable solar analyzer.
Authors: Rust, D. M.; Appourchaux, T.
1988ESASP.286..227R    Altcode: 1988ssls.rept..227R
  This paper presents a progress report on the development of an
  instrument with very high (1:10<SUP>10</SUP>) wavelength stability
  designed to measure solar surface velocities and magnetic fields. The
  instrument determines Doppler and Zeeman shifts in solar spectral lines
  by a 6-point weighted average. It is built around an electrically
  tunable solid lithium-niobate Fabry-Perot etalon that is stabilized
  against a diode laser which itself is locked to a resonance line
  of cesium 133. Key features are the unique etalon, which acts as a
  wide-angle 0.017-nm solar filter, the camera with a specially stabilized
  shutter, and the instrument control and data collection system. Use
  of the instrument in helioseismological research is emphasized.

---------------------------------------------------------
Title: Solar oscillations instrumentation and measurement theory.
Authors: Appourchaux, T.
1988ESASP.286..595A    Altcode: 1988ssls.rept..595A
  Solar-oscillation instruments have many common characteristics, such as
  detecting solar radial velocities on Fraunhofer lines with a 2-point
  measuring technique, high spectral resolution and stability, etc... A
  review of these common effects is made which can be used for optimizing
  most instruments in helioseismology. The choice of the spectral line
  is addressed for getting a high signal to solar noise ratio. Velocity
  imaging of solar oscillations modes is detailed including spatial
  sampling and span, highest observable degree. Applications of these
  different analysis is then applied to existing or future helioseismology
  instruments.

---------------------------------------------------------
Title: Performance of a Stabilized Fabry-Perot Solar Analyzer
Authors: Rust, D. M.; Appourchaux, T.; Hill, F.
1988IAUS..123..475R    Altcode:
  A unique solar lineshift analyzer described by Rust, Burton and Leistner
  (1986) has been used to study solar oscillations. Operation of this
  "Stabilized Solar Analyzer" depends on the electro-optic effect in
  crystalline lithium niobate, the substrate of the solid Fabry-Perot
  etalon. For 10 days in February, 1986, at the Vacuum Tower Telescope
  of the Sacramento Peak Observatory, the authors obtained full-disk
  observations of the solar oscillations.

---------------------------------------------------------
Title: Rotation in the Solar Convection Zone Inferred from Fabry-Perot
    Observations of the 5-MIN Oscillations
Authors: Hill, F.; Rust, D. M.; Appourchaux, T.
1988IAUS..123...49H    Altcode:
  Full disk observations of the 5-min solar oscillations have been
  obtained with a lithium niobate Fabry-Perot filter. The equatorial
  solar rotation rate as a function of depth has been inferred from the
  sectoral modes of oscillation using the Backus-Gilbert optimal averaging
  inversion method. The results show a rotation rate that slowly decreases
  over the depths of 15 to 56 Mm below the photosphere. The results are
  in agreement with the previous Duvall-Harvey observations.

---------------------------------------------------------
Title: The Faraday effect in a magneto-optical filter.
Authors: Appourchaux, T.
1987SoPh..109..393A    Altcode:
  A magneto-optical filter was built to establish its utility for
  measuring solar oscillations. A theoretical model is described and
  the asymptotic behaviour of the Faraday effect in the filter is
  deduced. Experimental work confirms to first order the asymptotic model.

---------------------------------------------------------
Title: Observations of Solar Oscillations with a Fabry-Perot Etalon
Authors: Rust, D. M.; Hill, F.; Appourchaux, T.
1987BAAS...19R.933R    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Correction of Atmospheric Transparency Gradient Effect on
    Solar Radial Velocities
Authors: Appourchaux, T.
1984srps.conf..117A    Altcode:
  The author has found that the major part of the atmospheric gradient
  is that computable from sec z and standard atmospheric tables. Thus
  a reasonable first approximation of the velocity correction can be
  obtained simply by computation. The autor has demonstrated a simple
  system for measuring the actual gradient from which the effective
  spurious velocity can be computed using standard figures for limb
  darkening and solar rotation.

---------------------------------------------------------
Title: Développement d'un Fabry-Perot destiné à l'observation des
oscillations solaires pour une mission spatiale 

---------------------------------------------------------
Title: Développement
    d'un Fabry-Perot destiné à l'observation des oscillations solaires
pour une mission spatiale 

---------------------------------------------------------
Title: Development of a Fabry-Perot
    interferometer for the observation of solar oscillations from a
    space mission;
Authors: Appourchaux, Thierry
1984PhDT........97A    Altcode:
  No abstract at ADS