explanation      blue bibcodes open ADS page with paths to full text
Author name code: culhane
ADS astronomy entries on 2022-09-14
=author:"Culhane, J.L." OR =author:"Culhane, Len" 

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Title: Photospheric and Coronal Abundances in an X8.3 Class Limb Flare
Authors: Doschek, G. A.; Warren, H. P.; Harra, L. K.; Culhane, J. L.;
   Watanabe, T.; Hara, H.
2018ApJ...853..178D    Altcode:
  We analyze solar elemental abundances in coronal post-flare
  loops of an X8.3 flare (SOL2017-09-10T16:06) observed on the west
  limb on 2017 September 10 near 18 UT using spectra recorded by
  the Extreme-ultraviolet Imaging Spectrometer (EIS) on the Hinode
  spacecraft. The abundances in the corona can differ from photospheric
  abundances due to the first ionization potential (FIP) effect. In
  some loops of this flare, we find that the abundances appear to be
  coronal at the loop apices or cusps, but steadily transform from
  coronal to photospheric as the loop footpoint is approached. This
  result is found from the intensity ratio of a low-FIP ion spectral
  line (Ca XIV) to a high-FIP ion spectral line (Ar XIV) formed at
  about the same temperature (4-5 MK). Both lines are observed close in
  wavelength. Temperature, which could alter the interpretation, does
  not appear to be a factor based on intensity ratios of Ca XV lines
  to a Ca XIV line. We discuss the abundance result in terms of the
  Laming model of the FIP effect, which is explained by the action of
  the ponderomotive force in magnetohydrodynamic (MHD) waves in coronal
  loops and in the underlying chromosphere.

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Title: Non-thermal distributions and energy transport in the solar
    flares
Authors: Matthews, Sarah; del Zanna, Guilio; Calcines, Ariadna;
   Mason, Helen; Mathioudakis, Mihalis; Culhane, Len; Harra, Louise;
   van Driel-Gesztelyi, Lidia; Green, Lucie; Long, David; Baker, Deb;
   Valori, Gherardo
2017arXiv171200773M    Altcode:
  Determining the energy transport mechanisms in flares remains a central
  goal in solar flares physics that is still not adequately answered
  by the 'standard flare model'. In particular, the relative roles of
  particles and/or waves as transport mechanisms, the contributions of low
  energy protons and ions to the overall flare budget, and the limits of
  low energy non-thermal electron distribution are questions that still
  cannot be adequately reconciled with current instrumentation. In this
  'White Paper' submitted in response to the call for inputs to the Next
  Generation Solar Physics Mission review process initiated by JAXA,
  NASA and ESA in 2016, we outline the open questions in this area and
  possible instrumentation that could provide the required observations
  to help answer these and other flare-related questions.

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Title: Helioseismology and Dynamics of the Solar Interior
Authors: Thompson, M. J.; Brun, A. S.; Culhane, J. L.; Gizon, L.;
   Roth, M.; Sekii, T.
2017hdsi.book.....T    Altcode:
  No abstract at ADS

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Title: Erratum to: The Magnetic Helicity Budget of a CME-Prolific
    Active Region
Authors: Green, L. M.; López Fuentes, M.; Mandrini, C. H.; Démoulin,
   P.; van Driel-Gesztelyi, L.; Culhane, J. L.
2016SoPh..291..335G    Altcode: 2015SoPh..tmp..179G
  No abstract at ADS

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Title: A Comparison of Global Magnetic Field Skeletons and
    Active-Region Upflows
Authors: Edwards, S. J.; Parnell, C. E.; Harra, L. K.; Culhane, J. L.;
   Brooks, D. H.
2016SoPh..291..117E    Altcode: 2015SoPh..tmp..161E
  Plasma upflows have been detected in active regions using Doppler
  velocity maps. The origin and nature of these upflows is not well known
  with many of their characteristics determined from the examination
  of single events. In particular, some studies suggest these upflows
  occur along open field lines and, hence, are linked to sources of
  the solar wind. To investigate the relationship these upflows may
  have with the solar wind, and to probe what may be driving them, this
  paper considers seven active regions observed on the solar disc using
  the Extreme ultraviolet Imaging Spectrometer aboard Hinode between
  August 2011 and September 2012. Plasma upflows are observed in all
  these active regions. The locations of these upflows are compared
  to the global potential magnetic field extrapolated from the Solar
  Dynamics Observatory, Helioseismic and Magnetic Imager daily synoptic
  magnetogram taken on the day the upflows were observed. The structure
  of the magnetic field is determined by constructing its magnetic
  skeleton in order to help identify open-field regions and also sites
  where magnetic reconnection at global features is likely to occur. As
  a further comparison, measurements of the temperature, density and
  composition of the plasma are taken from regions with active-region
  upflows. In most cases the locations of the upflows in the active
  regions do not correspond to areas of open field, as predicted by
  a global coronal potential-field model, and therefore these upflows
  are not always sources of the slow solar wind. The locations of the
  upflows are, in general, intersected by separatrix surfaces associated
  with null points located high in the corona; these could be important
  sites of reconnection with global consequences.

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Title: How Can Active Region Plasma Escape into the Solar Wind from
    Below a Closed Helmet Streamer?
Authors: Mandrini, C. H.; Nuevo, F. A.; Vásquez, A. M.; Démoulin,
   P.; van Driel-Gesztelyi, L.; Baker, D.; Culhane, J. L.; Cristiani,
   G. D.; Pick, M.
2014SoPh..289.4151M    Altcode: 2014arXiv1409.7369M; 2014SoPh..tmp..115M
  Recent studies show that active-region (AR) upflowing plasma,
  observed by the EUV-Imaging Spectrometer (EIS) onboard Hinode, can
  gain access to open-field lines and be released into the solar wind
  (SW) via magnetic-interchange reconnection at magnetic null-points in
  pseudo-streamer configurations. When only one bipolar AR is present
  on the Sun and is fully covered by the separatrix of a streamer, such
  as AR 10978 in December 2007, it seems unlikely that the upflowing AR
  plasma can find its way into the slow SW. However, signatures of plasma
  with AR composition have been found at 1 AU by Culhane et al. (Solar
  Phys.289, 3799, 2014) that apparently originated west of AR 10978. We
  present a detailed topology analysis of AR 10978 and the surrounding
  large-scale corona based on a potential-field source-surface (PFSS)
  model. Our study shows that it is possible for the AR plasma to move
  around the streamer separatrix and be released into the SW via magnetic
  reconnection, which occurs in at least two main steps. We analyse data
  from the Nançay Radioheliograph (NRH) in a search for evidence of the
  chain of magnetic reconnections that we propose. We find a noise storm
  above the AR and several varying sources at 150.9 MHz. Their locations
  suggest that they might be associated with particles accelerated during
  the first-step reconnection process at a null point well outside of
  the AR. We find no evidence of the second reconnection step in the
  radio data, however. Our results demonstrate that even when it appears
  highly improbable for the AR plasma to reach the SW, indirect channels
  involving a sequence of reconnections can make it possible.

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Title: Tracking Solar Active Region Outflow Plasma from Its Source
    to the Near-Earth Environment
Authors: Culhane, J. L.; Brooks, D. H.; van Driel-Gesztelyi, L.;
   Démoulin, P.; Baker, D.; DeRosa, M. L.; Mandrini, C. H.; Zhao, L.;
   Zurbuchen, T. H.
2014SoPh..289.3799C    Altcode: 2014SoPh..tmp...90C; 2014arXiv1405.2949C
  Seeking to establish whether active-region upflow material contributes
  to the slow solar wind, we examine in detail the plasma upflows from
  Active Region (AR) 10978, which crossed the Sun's disc in the interval 8
  to 16 December 2007 during Carrington rotation (CR) 2064. In previous
  work, using data from the Hinode/EUV Imaging Spectrometer, upflow
  velocity evolution was extensively studied as the region crossed the
  disc, while a linear force-free-field magnetic extrapolation was used
  to confirm aspects of the velocity evolution and to establish the
  presence of quasi-separatrix layers at the upflow source areas. The
  plasma properties, temperature, density, and first ionisation potential
  bias [FIP-bias] were measured with the spectrometer during the disc
  passage of the active region. Global potential-field source-surface
  (PFSS) models showed that AR 10978 was completely covered by the
  closed field of a helmet streamer that is part of the streamer
  belt. Therefore it is not clear how any of the upflowing AR-associated
  plasma could reach the source surface at 2.5 R<SUB>⊙</SUB> and
  contribute to the slow solar wind. However, a detailed examination of
  solar-wind in-situ data obtained by the Advanced Composition Explorer
  (ACE) spacecraft at the L<SUB>1</SUB> point shows that increases in
  O<SUP>7+</SUP>/O<SUP>6+</SUP>, C<SUP>6+</SUP>/C<SUP>5+</SUP>, and Fe/O -
  a FIP-bias proxy - are present before the heliospheric current-sheet
  crossing. These increases, along with an accompanying reduction in
  proton velocity and an increase in density are characteristic of
  both AR and slow-solar-wind plasma. Finally, we describe a two-step
  reconnection process by which some of the upflowing plasma from the
  AR might reach the heliosphere.

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Title: The Location of Non-thermal Velocity in the Early Phases of
    Large Flares—Revealing Pre-eruption Flux Ropes
Authors: Harra, Louise K.; Matthews, Sarah; Culhane, J. L.; Cheung,
   Mark C. M.; Kontar, Eduard P.; Hara, Hirohisa
2013ApJ...774..122H    Altcode:
  Non-thermal velocity measurements of the solar atmosphere, particularly
  from UV and X-ray emission lines have demonstrated over the decades
  that this parameter is important in understanding the triggering of
  solar flares. Enhancements have often been observed before intensity
  enhancements are seen. However, until the launch of Hinode, it has
  been difficult to determine the spatial location of the enhancements to
  better understand the source region. The Hinode EUV Imaging Spectrometer
  has the spectral and spatial resolution to allow us to probe the early
  stages of flares in detail. We analyze four events, all of which
  are GOES M- or X-classification flares, and all are located toward
  the limb for ease of flare geometry interpretation. Three of the
  flares were eruptive and one was confined. In all events, pre-flare
  enhancement in non-thermal velocity at the base of the active region
  and its surroundings has been found. These enhancements seem to be
  consistent with the footpoints of the dimming regions, and hence may
  be highlighting the activation of a coronal flux rope for the three
  eruptive events. In addition, pre-flare enhancements in non-thermal
  velocity were found above the looptops for the three eruptive events.

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Title: Observing Photons in Space: A Guide to Experimental Astronomy
Authors: Huber, M. C. E.; Pauluhn, A.; Culhane, J. L.; Timothy, J. G.;
   Wilhelm, K.; Zehnder, A.
2013opsg.book.....H    Altcode:
  No abstract at ADS

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Title: Plasma outflows at the border of active regions and the
    solar wind
Authors: Nuevo, F. A.; Mandrini, C. H.; Vásquez, A. M.; Deumoulin,
   P.; Van Driel-Gesztely, L.; Baker, D.; Cristiani, G. D.; Pick, M.;
   Culhane, J. L.
2013BAAA...56..387N    Altcode:
  We present a detailed topological analysis of active region (AR)
  10978; based on a Potential Field Source Surface (PFSS) model. AR
  10978 is a standard bipolar region which appears fully covered by
  the magnetic field lines of a coronal streamer. Despite this simple
  magnetic configuration; our analysis shows that it is possible for
  the AR plasma; contained in the outflows observed at the AR borders;
  to be released into the solar wind via magnetic reconnection.

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Title: Observing Photons in Space: A Guide to Experimental Spae
    Astronomy
Authors: Huber, M. C. E.; Pauluhn, A.; Culhane, J. L.; Timothy, J. G.;
   Wilhelm, K.; Zehnder, A.
2013ops..book.....H    Altcode:
  No abstract at ADS

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Title: Tracking Solar Active Region Outflow Plasma from its Source
    to the near-Earth Environment
Authors: Culhane, J. L.; Brooks, D.; Zurbuchen, T.; van
   Driel-Gesztelyi, L.; Fazakerley, A. N.; DeRosa, M. L.
2012AGUFMSH53A2255C    Altcode:
  In a recent study of persistent active region outflow from AR 10978 in
  the period 10 - 15, December, 2007, Brooks and Warren (2011), using the
  Hinode EUV Imaging Spectrometer (EIS) instrument showed the presence
  of a strong low-FIP element enhancement in the outflowing plasma that
  was replicated three days later in the in-situ solar wind measurements
  made by the ACE/SWICS instrument. In the present work, we examine the
  outflowing plasma properties (Te, Ne, v, abundances) as a function
  of time in greater detail as AR 10978 passes the Earth-Sun line. The
  structure of the magnetic field above the two outflow regions - E and
  W of the AR, is also examined. Following an assessment of the relevant
  magnetic structures between Sun and Earth, the properties of the solar
  wind plasma arriving at ACE approximately three days later are measured
  and compared with those of the outflowing AR plasma. The relationship
  of these measurements to the in-situ magnetic field observed by the
  ACE magnetometer is also studied. Finally the role of persistent AR
  outflows in contributing to the slow solar wind is assessed.

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Title: Magnetic Topology of Active Regions and Coronal Holes:
    Implications for Coronal Outflows and the Solar Wind
Authors: van Driel-Gesztelyi, L.; Culhane, J. L.; Baker, D.; Démoulin,
   P.; Mandrini, C. H.; DeRosa, M. L.; Rouillard, A. P.; Opitz, A.;
   Stenborg, G.; Vourlidas, A.; Brooks, D. H.
2012SoPh..281..237V    Altcode: 2012SoPh..tmp..228V
  During 2 - 18 January 2008 a pair of low-latitude opposite-polarity
  coronal holes (CHs) were observed on the Sun with two active regions
  (ARs) and the heliospheric plasma sheet located between them. We use
  the Hinode/EUV Imaging Spectrometer (EIS) to locate AR-related outflows
  and measure their velocities. Solar-Terrestrial Relations Observatory
  (STEREO) imaging is also employed, as are the Advanced Composition
  Explorer (ACE) in-situ observations, to assess the resulting impacts on
  the solar wind (SW) properties. Magnetic-field extrapolations of the two
  ARs confirm that AR plasma outflows observed with EIS are co-spatial
  with quasi-separatrix layer locations, including the separatrix of a
  null point. Global potential-field source-surface modeling indicates
  that field lines in the vicinity of the null point extend up to the
  source surface, enabling a part of the EIS plasma upflows access
  to the SW. We find that similar upflow properties are also observed
  within closed-field regions that do not reach the source surface. We
  conclude that some of plasma upflows observed with EIS remain confined
  along closed coronal loops, but that a fraction of the plasma may be
  released into the slow SW. This suggests that ARs bordering coronal
  holes can contribute to the slow SW. Analyzing the in-situ data, we
  propose that the type of slow SW present depends on whether the AR is
  fully or partially enclosed by an overlying streamer.

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Title: Characteristics of the Nonthermal Velocity Signature Observed
    in the Impulsive Phase of the 2007 May 19 Flare
Authors: Hara, H.; Watanabe, T.; Bone, L. A.; Culhane, J. L.; van
   Driel-Gesztelyi, L.; Young, P. R.
2009ASPC..415..459H    Altcode:
  The Hinode EUV Imaging Spectrometer (EIS) observed a long duration
  flare with a weak impulsive phase that appears to conform to the
  standard two-ribbon flare reconnection model. EIS scanned the flare
  site during the impulsive phase and observed Fe XXIII and Fe XXIV line
  emission that closely followed the flare hard X-ray emission while the
  line profiles showed significant non-thermal broadening. We suggest
  that a shock originating at the reconnection site which sweeps up and
  heats the coronal plasma can account for our observations.

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Title: Formation, Interaction and Merger of an Active Region and a
    Quiescent Filament Prior to Their Eruption on 19 May 2007
Authors: Bone, L. A.; van Driel-Gesztelyi, L.; Culhane, J. L.;
   Aulanier, G.; Liewer, P.
2009SoPh..259...31B    Altcode:
  We report observations of the formation of two filaments - one
  active and one quiescent, and their subsequent interactions prior to
  eruption. The active region filament appeared on 17 May 2007, followed
  by the quiescent filament about 24 hours later. In the 26 hour interval
  preceding the eruption, which occurred at around 12:50 UT on 19 May
  2007, we see the two filaments attempting to merge and filament material
  is repeatedly heated suggesting magnetic reconnection. The filament
  structure is observed to become increasingly dynamic preceding the
  eruption with two small hard X-ray sources seen close to the active
  part of the filament at around 01:38 UT on 19 May 2007 during one of
  the activity episodes. The final eruption on 19 May at about 12:51 UT
  involves a complex CME structure, a flare and a coronal wave. A magnetic
  cloud is observed near Earth by the STEREO-B and WIND spacecraft about
  2.7 days later. Here we describe the behaviour of the two filaments
  in the period prior to the eruption and assess the nature of their
  dynamic interactions.

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Title: Stereoscopic Analysis of the 19 May 2007 Erupting Filament
Authors: Liewer, P. C.; De Jong, E. M.; Hall, J. R.; Howard, R. A.;
   Thompson, W. T.; Culhane, J. L.; Bone, L.; van Driel-Gesztelyi, L.
2009SoPh..256...57L    Altcode: 2009arXiv0904.1055L
  A filament eruption, accompanied by a B9.5 flare, coronal dimming,
  and an EUV wave, was observed by the Solar TERrestrial Relations
  Observatory (STEREO) on 19 May 2007, beginning at about 13:00 UT. Here,
  we use observations from the SECCHI/EUVI telescopes and other solar
  observations to analyze the behavior and geometry of the filament before
  and during the eruption. At this time, STEREO A and B were separated by
  about 8.5°, sufficient to determine the three-dimensional structure
  of the filament using stereoscopy. The filament could be followed in
  SECCHI/EUVI 304 Å stereoscopic data from about 12 hours before to about
  2 hours after the eruption, allowing us to determine the 3D trajectory
  of the erupting filament. From the 3D reconstructions of the filament
  and the chromospheric ribbons in the early stage of the eruption,
  simultaneous heating of both the rising filamentary material and the
  chromosphere directly below is observed, consistent with an eruption
  resulting from magnetic reconnection below the filament. Comparisons
  of the filament during eruption in 304 Å and Hα show that when it
  becomes emissive in He II, it tends to disappear in Hα , indicating
  that the disappearance probably results from heating or motion, not
  loss, of filamentary material.

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Title: Magnetic Flux Emergence, Activity, Eruptions and Magnetic
Clouds: Following Magnetic Field from the Sun to the Heliosphere
Authors: van Driel-Gesztelyi, L.; Culhane, J. L.
2009SSRv..144..351V    Altcode: 2008SSRv..tmp..185V
  We present an overview of how the principal physical properties of
  magnetic flux which emerges from the toroidal fields in the tachocline
  through the turbulent convection zone to the solar surface are linked
  to solar activity events, emphasizing the effects of magnetic field
  evolution and interaction with other magnetic structures on the
  latter. We compare the results of different approaches using various
  magnetic observables to evaluate the probability of flare and coronal
  mass ejection (CME) activity and forecast eruptive activity on the
  short term (i.e. days). Then, after a brief overview of the observed
  properties of CMEs and their theoretical models, we discuss the
  ejecta properties and describe some typical magnetic and composition
  characteristics of magnetic clouds (MCs) and interplanetary CMEs
  (ICMEs). We review some individual examples to clarify the link between
  eruptions from the Sun and the properties of the resulting ejecta. The
  importance of a synthetic approach to solar and interplanetary magnetic
  fields and activity is emphasized.

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Title: The Origin and Dynamics of Solar Magnetism
Authors: Thompson, M. J.; Balogh, A.; Culhane, J. L.; Nordlund, Å.;
   Solanki, S. K.; Zahn, J. -P.
2009odsm.book.....T    Altcode:
  No abstract at ADS

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Title: Magnetic Flux Emergence, Activity, Eruptions and Magnetic
Clouds: Following Magnetic Field from the Sun to the Heliosphere
Authors: van Driel-Gesztelyi, L.; Culhane, J. L.
2009odsm.book..351V    Altcode:
  We present an overview of how the principal physical properties of
  magnetic flux which emerges from the toroidal fields in the tachocline
  through the turbulent convection zone to the solar surface are linked
  to solar activity events, emphasizing the effects of magnetic field
  evolution and interaction with other magnetic structures on the
  latter. We compare the results of different approaches using various
  magnetic observables to evaluate the probability of flare and coronal
  mass ejection (CME) activity and forecast eruptive activity on the
  short term (i.e. days). Then, after a brief overview of the observed
  properties of CMEs and their theoretical models, we discuss the
  ejecta properties and describe some typical magnetic and composition
  characteristics of magnetic clouds (MCs) and interplanetary CMEs
  (ICMEs). We review some individual examples to clarify the link between
  eruptions from the Sun and the properties of the resulting ejecta. The
  importance of a synthetic approach to solar and interplanetary magnetic
  fields and activity is emphasized.

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Title: Flows and Nonthermal Velocities in Solar Active Regions
Observed with the EUV Imaging Spectrometer on Hinode: A Tracer of
    Active Region Sources of Heliospheric Magnetic Fields?
Authors: Doschek, G. A.; Warren, H. P.; Mariska, J. T.; Muglach, K.;
   Culhane, J. L.; Hara, H.; Watanabe, T.
2008ApJ...686.1362D    Altcode: 2008arXiv0807.2860D
  From Doppler velocity maps of active regions constructed from spectra
  obtained by the EUV Imaging Spectrometer (EIS) on the Hinode spacecraft
  we observe large areas of outflow (20-50 km s<SUP>-1</SUP>) that can
  persist for at least a day. These outflows occur in areas of active
  regions that are faint in coronal spectral lines formed at typical
  quiet-Sun and active region temperatures. The outflows are positively
  correlated with nonthermal velocities in coronal plasmas. The bulk
  mass motions and nonthermal velocities are derived from spectral line
  centroids and line widths, mostly from a strong line of Fe XII at
  195.12 Å. The electron temperature of the outflow regions estimated
  from an Fe XIII to Fe XII line intensity ratio is about (1.2-1.4) ×
  10<SUP>6</SUP> K. The electron density of the outflow regions derived
  from a density-sensitive intensity ratio of Fe XII lines is rather low
  for an active region. Most regions average around 7 × 10<SUP>8</SUP>
  cm<SUP>-3</SUP>, but there are variations on pixel spatial scales
  of about a factor of 4. We discuss results in detail for two active
  regions observed by EIS. Images of active regions in line intensity,
  line width, and line centroid are obtained by rastering the regions. We
  also discuss data from the active regions obtained from other orbiting
  spacecraft that support the conclusions obtained from analysis of the
  EIS spectra. The locations of the flows in the active regions with
  respect to the longitudinal photospheric magnetic fields suggest that
  these regions might be tracers of long loops and/or open magnetic
  fields that extend into the heliosphere, and thus the flows could
  possibly contribute significantly to the solar wind.

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Title: Multi-scale reconnections in a complex CME
Authors: van Driel-Gesztelyi, L.; Goff, C. P.; Démoulin, P.; Culhane,
   J. L.; Matthews, S. A.; Harra, L. K.; Mandrini, C. H.; Klein, K. -L.;
   Kurokawa, H.
2008AdSpR..42..858V    Altcode:
  A series of three flares of GOES class M, M and C, and a CME were
  observed on 20 January 2004 occurring in close succession in NOAA
  10540. Types II, III, and N radio bursts were associated. We use
  the combined observations from TRACE, EIT, Hα images from Kwasan
  Observatory, MDI magnetograms, GOES, and radio observations from
  Culgoora and Wind/ WAVES to understand the complex development of this
  event. We reach three main conclusions. First, we link the first two
  impulsive flares to tether-cutting reconnections and the launch of
  the CME. This complex observation shows that impulsive quadrupolar
  flares can be eruptive. Second, we relate the last of the flares, an
  LDE, to the relaxation phase following forced reconnections between
  the erupting flux rope and neighbouring magnetic field lines, when
  reconnection reverses and restores some of the pre-eruption magnetic
  connectivities. Finally, we show that reconnection with the magnetic
  structure of a previous CME launched about 8 h earlier injects electrons
  into open field lines having a local dip and apex (located at about six
  solar radii height). This is observed as an N-burst at decametre radio
  wavelengths. The dipped shape of these field lines is due to large-scale
  magnetic reconnection between expanding magnetic loops and open field
  lines of a neighbouring streamer. This particular situation explains
  why this is the first N-burst ever observed at long radio wavelengths.

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Title: Strongly Blueshifted Phenomena Observed with Hinode EIS in
    the 2006 December 13 Solar Flare
Authors: Asai, Ayumi; Hara, Hirohisa; Watanabe, Tetsuya; Imada,
   Shinsuke; Sakao, Taro; Narukage, Noriyuki; Culhane, J. L.; Doschek,
   G. A.
2008ApJ...685..622A    Altcode: 2008arXiv0805.4468A
  We present a detailed examination of strongly blueshifted emission
  lines observed with the EUV Imaging Spectrometer on board the Hinode
  satellite. We found two kinds of blueshifted phenomenon associated
  with the X3.4 flare that occurred on 2006 December 13. One was related
  to a plasmoid ejection seen in soft X-rays. It was very bright in all
  the lines used for the observations. The other was associated with the
  faint arc-shaped ejection seen in soft X-rays. The soft X-ray ejection
  is thought to be a magnetohydrodynamic (MHD) fast-mode shock wave. This
  is therefore the first spectroscopic observation of an MHD fast-mode
  shock wave associated with a flare.

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Title: Long Duration Flare Observed with Hinode EIS
Authors: Culhane, J. L.; Hara, H.; Watanabe, T.; Matsuzaki, K.; Harra,
   L. K.; Cargill, P.; Mariska, J. T.; Doschek, G. A.
2008ASPC..397..121C    Altcode:
  The first Long Duration Event (LDE) observed with Hinode EIS using
  a high spectral resolution raster scan is described. The hot plasma
  features include a cusp-shaped arcade associated with a thermal RHESSI
  source, cooling post-flare loops, complex plasma flows and an EIT
  observation that shows expanding loops and inflows characteristic of
  the standard magnetic reconnection model for solar flares. A Coronal
  Mass Ejection (CME) is also seen by LASCO. The cusp is well observed
  in the Ca XVII line and we find enhanced line broadening above this
  region. Doppler velocity observations for the post-flare loops show both
  up-flows and down-flows that are interpreted as due to siphon flows.

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Title: Long Duration Thermal Hard X-ray Sources Observed in Two
    Eruptive Flares
Authors: Bone, L. A.; Culhane, J. L.; van Driel-Gesztelyi, L.; Hara, H.
2008ASPC..397..160B    Altcode:
  We present observations of two eruptive flares on 17 of December
  2006 (C1.9) and 19 of May 2007 (B9.7) which had good coverage with
  both Hinode and RHESSI. In these flares we see a long lived, gradual
  thermal hard X-ray source of low emission measure and, relative to
  the loops observed with GOES and XRT, high temperature. The lack of a
  non-thermal hard X-ray component and impulsive behaviour is inconsistent
  with electron beam driven chromospheric evaporation.

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Title: Hinode EIS and XRT Observations of Hot Jets in Coronal Holes -
    Does the Plasma Escape?
Authors: Baker, D.; van Driel-Gesztelyi, L.; Kamio, S.; Culhane,
   J. L.; Harra, L. K.; Sun, J.; Young, P. R.; Matthews, S. A.
2008ASPC..397...23B    Altcode:
  X-ray jets have been detected in the extreme ultraviolet (EUV) and
  soft X-ray observations of Hinode's EIS and XRT instruments. Both
  instruments were used to observe the jets in polar and on-disk coronal
  holes (CHs). Here, we present a multi-wavelength study of an X-ray
  jet and its associated bright point found in an equatorial CH on 19
  June 2007. Light curves (LCs) in 22 different emission lines were
  compared to that of Hinode/XRT. As we found in a previous study of
  two polar X-ray jets, this jet shows a post-jet increase in its EUV
  LCs. The post-jet enhancement appears cooler than the jet. We suggest
  this feature arises because the hot plasma of the jet, having failed to
  reach escape speeds, cools and falls back along the near vertical paths
  expected to be created by reconnection with open field lines of CHs. In
  addition to the increase in post-jet EUV intensity, we found tentative
  evidence of impact heating possibly caused by the fall-back of plasma.

---------------------------------------------------------
Title: Study of Two Long Duration Eruptive Flares with the Hinode
    and RHESSI Spacecraft
Authors: Culhane, J. L.; Bone, L.; Williams, D. R.; Brooks, D. H.;
   Vandriel-Gesztelyi, L.; Hara, H.; Veronig, A.
2007AGUFMSH52C..05C    Altcode:
  Two eruptive flares that occurred on 17 December 2006 and 19 May
  2007 were observed by the instruments on the Hinode and RHESSI
  spacecraft. Both share some of the characteristics of the well known
  event observed with Yohkoh in February, 1992 (Tsuneta et al., 1992)
  in that they seem largely thermal in character and exhibit many of
  the features of the standard Carmichael, Hirayama, Sturrock, Kopp,
  Pneuman (CHSKP) flare model. However for these events, much additional
  (e.g. SOHO) data is available including the observation of an associated
  erupting filament on 19th May that was seen at the Kanzelhoehe Solar
  Observatory. In this talk the role of the outflow termination shock
  in heating the flare plasma will be re-examined. In particular the
  presence of plasma over a wide temperature range in the flare cusps
  and the possibility of non-thermal effects following the shock heating,
  will be assessed. The behaviour of the erupting filament material will
  also be discussed.

---------------------------------------------------------
Title: Solar Transition Region Features Observed with Hinode/EIS
Authors: Young, Peter R.; Del Zanna, Giulio; Mason, Helen E.; Doschek,
   George A.; Culhane, Len; Hara, Hirohisa
2007PASJ...59S.727Y    Altcode: 2007arXiv0706.1856Y
  Two types of solar active region feature prominent at transition region
  temperatures are identified in Hinode/EIS data of AR 10938 taken on
  2007 January 20. The footpoints of 1 MK TRACE loops are shown to emit
  strongly in emission lines formed at log T = 5.4-5.8, allowing the
  temperature increase along the footpoints to be clearly seen. A density
  diagnostic of Mg VII yields the density in the footpoints, with one
  loop showing a decrease from 3 × 10<SUP>9</SUP> cm<SUP>-3</SUP> at the
  base to 1.5 × 10<SUP>9</SUP> cm<SUP>-3</SUP> at a projected height
  of 20 Mm. The second feature is a compact active region transition
  region brightening which is particularly intense in O V emission
  (log T = 5.4) but also has a signature at temperatures up to log T =
  6.3. The Mg VII diagnostic gives a density of 4 × 10<SUP>10</SUP>
  cm<SUP>-3</SUP>, and emission lines of Mg VI and Mg VII show line
  profiles broadened by 50kms<SUP>-1</SUP> and wings extending beyond
  ± 200kms<SUP>-1</SUP>. Continuum emission in the short wavelength
  band is also found to be enhanced, and is suggested to be free-bound
  emission from recombination onto He<SUP>+</SUP>.

---------------------------------------------------------
Title: Hinode EUV Study of Jets in the Sun's South Polar Corona
Authors: Culhane, Len; Harra, Louise K.; Baker, Deborah; van
   Driel-Gesztelyi, Lidia; Sun, Jian; Doschek, George A.; Brooks, David
   H.; Lundquist, Loraine L.; Kamio, Suguru; Young, Peter R.; Hansteen,
   Viggo H.
2007PASJ...59S.751C    Altcode:
  A number of coronal bright points and associated plasma jet features
  were seen in an observation of the South polar coronal hole during
  2007 January. The 40" wide slot was used at the focus of the Hinode
  EUV Imaging Spectrometer to provide spectral images for two of these
  events. Light curves are plotted for a number of emission lines that
  include He II 256Å (0.079MK) and cover the temperature interval from
  0.4MK to 5.0MK. Jet speed measurements indicate values less than the
  escape velocity. The light curves show a post-jet enhancement in a
  number of the cooler coronal lines indicating that after a few minutes
  cooling, the plasma fell back to its original acceleration site. This
  behavior has not been previously observed by e.g., the Yohkoh Soft
  X-ray Telescope due to the comparatively high temperature cut-off
  in its response. The observations are consistent with the existing
  models that involve magnetic reconnection between emerging flux and the
  ambient open field lines in the polar coronal hole. However we do not
  have sufficient coverage of lines from lower temperature ion species
  to register the Hα-emitting surge material that is associated with
  some of these models.

---------------------------------------------------------
Title: Hot and Cool Loops Composing the Corona of the Quiet Sun
Authors: Matsuzaki, Keiichi; Hara, Hirohisa; Watanabe, Tetsuya; Dere,
   Kenneth P.; Brown, Charles M.; Culhane, Len
2007PASJ...59S.683M    Altcode:
  We performed a raster scan observation of the quiet Sun with the EUV
  Imaging Spectrometer (EIS) aboard Hinode and simultaneously analyzed
  observed emission lines of Fe VIII to XV. From a combined analysis,
  radiance maps from the observed emission lines were deconvolved into
  plasma components at five representative temperatures between 0.40MK and
  2.63MK. While the lowest temperature component shows network structures
  on spatial scales of between 10" and 20", the higher temperature
  components show thread-like patterns on larger scales. A comparison of
  emission measures at the different temperatures suggests that the lowest
  temperature component is mainly composed of bodies of small loops,
  rather than a collection of foot points of the higher temperature
  loops. The difference in morphologies is interpreted as being due to
  different magnetic field configurations, loops within super-granule
  cells and fields extending beyond the boundaries of super-granule cells,
  with distinct peak temperatures following a loop scaling law.

---------------------------------------------------------
Title: Temperature and Density Structures of Solar Corona, A Test
    of Iron Line Diagnostic Capability of EIS Instrument on Board Hinode
Authors: Watanabe, Tetsuya; Hara, Hirohisa; Culhane, Len; Harra,
   Louise K.; Doschek, George A.; Mariska, John T.; Young, Peter R.
2007PASJ...59S.669W    Altcode:
  Increased diagnostic capability of the EUV Imaging Spectrometer
  (EIS) aboard Hinode (former Solar-B) has been demonstrated with
  a set of iron emission lines emerging in the two EIS observing
  wavelength bands (170-210Å and 250-290Å) and their line-intensity
  ratios. “Abundance-uncertainty” free relative emission measure
  distributions as a function of temperature were deduced using only iron
  emission lines of various ionization stages. First-light spectra of a
  small active region show iron lines ranging from FeVIII (185.2Å and
  186.6Å) through FeXVII (204.7Å, 254.9Å, and 269.4Å). Spectra of a
  C-class flare confirms the presence of one of these higher temperature
  lines (FeXVII at 254.9Å) more clearly, as well showing FeXXIV (192.0Å
  and 255.1Å) and FeXXIII (263.8Å), which are normally only seen at
  flare temperatures.

---------------------------------------------------------
Title: The Temperature and Density Structure of an Active Region
    Observed with the Extreme-Ultraviolet Imaging Spectrometer on Hinode
Authors: Doschek, George A.; Mariska, John T.; Warren, Harry P.;
   Culhane, Len; Watanabe, Tetsuya; Young, Peter R.; Mason, Helen E.;
   Dere, Kenneth P.
2007PASJ...59S.707D    Altcode:
  The Extreme-Ultraviolet Imaging Spectrometer (EIS) on Hinode
  produces high resolution spectra that can be combined via rasters
  into monochromatic images of solar structures, such as active
  regions. Electron temperature and density maps of the structures can
  be obtained by imaging the structures in different spectral lines with
  ratios sensitive to either temperature or density. Doppler maps and
  ion temperature maps can be made from spectral line wavelengths and
  profiles, respectively. In this paper we discuss coronal temperature
  and density distributions within an active region, illustrating the
  power of EIS for solar plasma diagnostics.

---------------------------------------------------------
Title: EUV Emission Lines and Diagnostics Observed with Hinode/EIS
Authors: Young, Peter R.; Del Zanna, Giulio; Mason, Helen E.; Dere,
   Ken P.; Landi, Enrico; Landini, Massimo; Doschek, George A.; Brown,
   Charles M.; Culhane, Len; Harra, Louise K.; Watanabe, Tetsuya; Hara,
   Hirohisa
2007PASJ...59S.857Y    Altcode: 2007arXiv0706.1857Y
  Quiet Sun and active region spectra from the Hinode/EIS instrument are
  presented, and the strongest lines from different temperature regions
  discussed. A list of emission lines recommended to be included in EIS
  observation studies is presented based on analysis of blending and
  diagnostic potential using the CHIANTI atomic database. In addition
  we identify the most useful density diagnostics from the ions covered
  by EIS.

---------------------------------------------------------
Title: Velocity Structure of Jets in a Coronal Hole
Authors: Kamio, Suguru; Hara, Hirohisa; Watanabe, Tetsuya; Matsuzaki,
   Keiichi; Shibata, Kazunari; Culhane, Len; Warren, Harry P.
2007PASJ...59S.757K    Altcode: 2007arXiv0711.2848K
  The velocity structures of jets in a coronal hole have been derived
  for the first time. Hinode observations revealed the existence
  of many bright points in coronal holes. They are loop-shaped and
  sometimes associated with coronal jets. Spectra obtained with the
  Extreme-ultraviolet Imaging Spectrometer aboard Hinode were analyzed
  to infer the Doppler velocity of bright loops and jets in a coronal
  hole of the north polar region. Elongated jets above bright loops are
  found to be blue-shifted by 30kms<SUP>-1</SUP> at maximum, while foot
  points of bright loops are red-shifted. Blue-shifts detected in coronal
  jets are interpreted as being upflows produced by magnetic reconnection
  between emerging flux and the ambient field in the coronal hole.

---------------------------------------------------------
Title: Wavelength Determination for Solar Features Observed by the
    EUV Imaging Spectrometer on Hinode
Authors: Brown, Charles M.; Hara, Hirohisa; Kamio, Suguru; Feldman,
   Uri; Seely, John F.; Doschek, George A.; Mariska, John T.; Korendyke,
   Clarence M.; Lang, James; Dere, Kenneth P.; Culhane, Len; Thomas,
   Roger J.; Davila, Joseph M.
2007PASJ...59S.865B    Altcode:
  A wavelength calibration of solar lines observed by the high
  resolution EUV Imaging Spectrometer (EIS) on the Hinode satellite
  is reported. Spectral features of the quiet sun and of two mildly
  active areas were measured and calibrated. A listing of the stronger
  observed lines with identification of the leading contributor ions
  is presented. 41 lines are reported, with 90% identified. Wavelength
  precisions (2σ) of ±0.0031Å for the EIS short band and ±0.0029Å
  for the EIS long band are obtained. These lines, typical of 1-2
  ×10<SUP>6</SUP> K plasmas, are recommended as standards for the
  establishment of EIS wavelength scales. The temperature of EIS varies
  by about 1D.5 C around the orbit and also with spacecraft pointing. The
  correlation of these temperature changes with wavelength versus pixel
  number scale changes is reported.

---------------------------------------------------------
Title: The Solar-B EUV Imaging Spectrometer: an Overview of the
    EIS Instrument
Authors: Culhane, J. L.
2007ASPC..369....3C    Altcode:
  The Solar-B mission includes an Extreme-UV Imaging Spectrometer
  (EIS). This instrument detects photons in the wavelength ranges 170
  - 210 Å and 250 - 290 Å which include emission lines from several
  highly ionised species that exist over the temperature range of 4.7
  to 7.3 in Log T. In this summary paper, we will describe the design
  and operation of the instrument, present its performance parameters
  e.g. spectral and spatial resolution and sensitivity, and summarize
  its calibration. Its role in the Solar-B mission will be illustrated
  with reference to some key science topics. The anticipated observing
  strategy for the first three months of the mission will be outlined.

---------------------------------------------------------
Title: Nonthermal Velocities in Solar Active Regions Observed with
    the Extreme-Ultraviolet Imaging Spectrometer on Hinode
Authors: Doschek, G. A.; Mariska, J. T.; Warren, H. P.; Brown, C. M.;
   Culhane, J. L.; Hara, H.; Watanabe, T.; Young, P. R.; Mason, H. E.
2007ApJ...667L.109D    Altcode:
  We discuss nonthermal velocities in an active region as revealed
  by the Extreme-Ultraviolet Imaging Spectrometer (EIS) on the Hinode
  spacecraft. The velocities are derived from spectral line profiles in
  the extreme-ultraviolet (EUV) from a strong line of Fe XII at 195.12 Å
  by fitting each line profile to a Gaussian function. We compare maps
  of the full width at half-maximum values, the Fe XII spectral line
  intensity, the Fe XII Doppler shift, the electron temperature, and
  electron density. We find that the largest widths in the active region
  do not occur in the most intense regions, but seem to concentrate in
  less intense regions, some of which are directly adjacent to coronal
  loops, and some of which concentrate in regions which also exhibit
  relative Doppler outflows. The increased widths can also occur over
  extended parts of the active region.

---------------------------------------------------------
Title: CME Propagation Characteristics from Radio Observations
Authors: Pohjolainen, S.; van Driel-Gesztelyi, L.; Culhane, J. L.;
   Manoharan, P. K.; Elliott, H. A.
2007SoPh..244..167P    Altcode: 2007arXiv0711.3168P
  We explore the relationship among three coronal mass ejections (CMEs),
  observed on 28 October 2003, 7 November 2004, and 20 January 2005,
  the type II burst-associated shock waves in the corona and solar wind,
  as well as the arrival of their related shock waves and magnetic clouds
  at 1 AU. Using six different coronal/interplanetary density models,
  we calculate the speeds of shocks from the frequency drifts observed
  in metric and decametric radio wave data. We compare these speeds
  with the velocity of the CMEs as observed in the plane-of-the-sky
  white-light observations and calculated with a cone model for the 7
  November 2004 event. We then follow the propagation of the ejecta using
  Interplanetary Scintillation measurements, which were available for the
  7 November 2004 and 20 January 2005 events. Finally, we calculate the
  travel time of the interplanetary shocks between the Sun and Earth and
  discuss the velocities obtained from the different data. This study
  highlights the difficulties in making velocity estimates that cover
  the full CME propagation time.

---------------------------------------------------------
Title: The Sun - Earth Workshop: A Summary of the Outcome
Authors: Culhane, J. L.; Siscoe, G. L.
2007SoPh..244....3C    Altcode:
  This special issue includes a set of papers that deal with extended
  solar activity, the launching of CMEs at the Sun, their propagation
  through interplanetary space, and the detection and study of the
  ejecta near Earth and of their interaction with the Earth's magnetic
  environment. In particular solar events that occurred on 28 October
  2003, 6 and 7 November 2004, and 20 January 2005, for which the related
  shocks arrived at Earth about two days later, are considered. The
  summary paper extracts the principal outcomes that were arrived at in
  the areas treated during the workshop and seeks to draw conclusions
  both on the progress made and on possible directions for future work
  in these areas.

---------------------------------------------------------
Title: The EUV Imaging Spectrometer for Hinode
Authors: Culhane, J. L.; Harra, L. K.; James, A. M.; Al-Janabi, K.;
   Bradley, L. J.; Chaudry, R. A.; Rees, K.; Tandy, J. A.; Thomas, P.;
   Whillock, M. C. R.; Winter, B.; Doschek, G. A.; Korendyke, C. M.;
   Brown, C. M.; Myers, S.; Mariska, J.; Seely, J.; Lang, J.; Kent,
   B. J.; Shaughnessy, B. M.; Young, P. R.; Simnett, G. M.; Castelli,
   C. M.; Mahmoud, S.; Mapson-Menard, H.; Probyn, B. J.; Thomas, R. J.;
   Davila, J.; Dere, K.; Windt, D.; Shea, J.; Hagood, R.; Moye, R.; Hara,
   H.; Watanabe, T.; Matsuzaki, K.; Kosugi, T.; Hansteen, V.; Wikstol, Ø.
2007SoPh..243...19C    Altcode:
  The EUV Imaging Spectrometer (EIS) on Hinode will observe solar corona
  and upper transition region emission lines in the wavelength ranges
  170 - 210 Å and 250 - 290 Å. The line centroid positions and profile
  widths will allow plasma velocities and turbulent or non-thermal line
  broadenings to be measured. We will derive local plasma temperatures and
  densities from the line intensities. The spectra will allow accurate
  determination of differential emission measure and element abundances
  within a variety of corona and transition region structures. These
  powerful spectroscopic diagnostics will allow identification
  and characterization of magnetic reconnection and wave propagation
  processes in the upper solar atmosphere. We will also directly study
  the detailed evolution and heating of coronal loops. The EIS instrument
  incorporates a unique two element, normal incidence design. The optics
  are coated with optimized multilayer coatings. We have selected highly
  efficient, backside-illuminated, thinned CCDs. These design features
  result in an instrument that has significantly greater effective area
  than previous orbiting EUV spectrographs with typical active region
  2 - 5 s exposure times in the brightest lines. EIS can scan a field
  of 6×8.5 arc min with spatial and velocity scales of 1 arc sec and
  25 km s<SUP>−1</SUP> per pixel. The instrument design, its absolute
  calibration, and performance are described in detail in this paper. EIS
  will be used along with the Solar Optical Telescope (SOT) and the X-ray
  Telescope (XRT) for a wide range of studies of the solar atmosphere.

---------------------------------------------------------
Title: The Hinode (Solar-B) Mission: An Overview
Authors: Kosugi, T.; Matsuzaki, K.; Sakao, T.; Shimizu, T.; Sone,
   Y.; Tachikawa, S.; Hashimoto, T.; Minesugi, K.; Ohnishi, A.; Yamada,
   T.; Tsuneta, S.; Hara, H.; Ichimoto, K.; Suematsu, Y.; Shimojo, M.;
   Watanabe, T.; Shimada, S.; Davis, J. M.; Hill, L. D.; Owens, J. K.;
   Title, A. M.; Culhane, J. L.; Harra, L. K.; Doschek, G. A.; Golub, L.
2007SoPh..243....3K    Altcode:
  The Hinode satellite (formerly Solar-B) of the Japan Aerospace
  Exploration Agency's Institute of Space and Astronautical Science
  (ISAS/JAXA) was successfully launched in September 2006. As the
  successor to the Yohkoh mission, it aims to understand how magnetic
  energy gets transferred from the photosphere to the upper atmosphere
  and results in explosive energy releases. Hinode is an observatory
  style mission, with all the instruments being designed and built to
  work together to address the science aims. There are three instruments
  onboard: the Solar Optical Telescope (SOT), the EUV Imaging Spectrometer
  (EIS), and the X-Ray Telescope (XRT). This paper provides an overview
  of the mission, detailing the satellite, the scientific payload, and
  operations. It will conclude with discussions on how the international
  science community can participate in the analysis of the mission data.

---------------------------------------------------------
Title: Hinode Euv Study Of Jets In The Sun’s South Polar Corona
Authors: Culhane, J. L.; Brooks, D. H.; Doschek, G. A.; Harra, L. K.;
   van Driel-Gesztelyi, L.; Baker, D.; Lundquist, L. L.; Hansteen, V. H.;
   Kamio, S.
2007AAS...210.7201C    Altcode: 2007BAAS...39..178C
  Using the Hinode EUV Imaging Spectrometer coronal jets were observed
  on 20-JAN-2007 over a range of emission lines and corresponding plasma
  temperatures using the 40 arc sec wide slot images. In this preliminary
  analysis, jet plasma temperature and emissivity have been estimated
  while, based on assumptions about the jet morphology, electron density
  estimates are given and jet velocity measured. The evolution of the
  jets will be followed in a number of different EUV emission lines and
  jet energy input as a function of time will be assessed with reference
  to the magnetic field topologies involved.

---------------------------------------------------------
Title: Hinode EIS Observations of Solar Active Regions
Authors: Mariska, John T.; Doschek, G. A.; Warren, H. P.; Brooks,
   D. H.; Young, P. R.; Watanabe, T.; Culhane, J. L.
2007AAS...210.7202M    Altcode: 2007BAAS...39R.178M
  The EUV Imaging Spectrometer (EIS) on the Hinode satellite provides
  high spatial and spectral resolution data along a 512 arcsec slit in
  two wavelength ranges, 170--210 Angstroms and 250--290 Angstroms. These
  wavelengths mostly contain emission lines from upper transition region
  and coronal plasmas. Emission from these wavelengths is routinely
  imaged using instruments such as the EIT on SOHO and TRACE, but there
  are few high-resolution spectra to aid in more deeply understanding
  the physical conditions and dynamics associated with the intensity
  variations seen in the images. In this presentation, we show some
  initial results from EIS active region studies aimed at mapping the
  density, temperature, nonthermal broadening, and Doppler shifts in
  active regions. This presentation focusses on spectroheliograms of
  active regions in diagnostically interesting spectral lines. These
  show the overall active region morphology and the behavior of Doppler
  shifts, nonthermal velocities, and densities as a function of position,
  but at the expense of high time resolution. Other presentations will
  focus on how the observed physical parameters vary with time.

---------------------------------------------------------
Title: Iron Line Ratio Analysis in an Active Region
Authors: Watanabe, Tetsuya; Hara, H.; Culhane, J. L.; Harra, L. K.;
   Doschek, G. A.; Mariska, J. T.; Young, P. R.; Hinode EIS Team
2007AAS...210.7204W    Altcode: 2007BAAS...39..179W
  Increased diagnostic capability of the EIS instrument on board Hinode
  (Solar-B) is demonstrated with a set of iron emission lines appearing
  in the two EIS observing wavelengths (170 - 210 A &amp; 250 - 290
  A) and their line intensity ratios. First-light spectra of a small
  active region show iron lines at the ionization stages of FeVIII
  (185.2 A &amp; 186.6 A) through FeXVII (204.7 A, 254.9 A, &amp; 269.4
  A). Decay phase spectra of a C-class flare confirms the presence of
  this higher temperature line; FeXVII at 254.9 A more clearly, as well
  as those lines of flare temperatures; FeXXIV (192.0 A &amp; 255.1 A)
  and FeXXIII (263.8 A).

---------------------------------------------------------
Title: A Multiple Flare Scenario where the Classic Long-Duration
    Flare Was Not the Source of a CME
Authors: Goff, C. P.; van Driel-Gesztelyi, L.; Démoulin, P.; Culhane,
   J. L.; Matthews, S. A.; Harra, L. K.; Mandrini, C. H.; Klein, K. L.;
   Kurokawa, H.
2007SoPh..240..283G    Altcode:
  A series of flares (GOES class M, M and C) and a CME were observed in
  close succession on 20 January 2004 in NOAA 10540. Radio observations,
  which took the form of types II, III and N bursts, were associated with
  these events. We use the combined observations from TRACE, EIT, Hα
  images from Kwasan, MDI magnetograms and GOES to understand the complex
  development of this event. Contrary to a standard interpretation,
  we conclude that the first two impulsive flares are part of the CME
  launch process while the following long-duration event flare represents
  simply the recovery phase. Observations show that the flare ribbons
  not only separate but also shift along the magnetic inversion line
  so that magnetic reconnection progresses stepwise to neighboring flux
  tubes. We conclude that "tether cutting" reconnection in the sheared
  arcade progressively transforms it to a twisted flux tube, which
  becomes unstable, leading to a CME. We interpret the third flare,
  a long-duration event, as a combination of the classical two-ribbon
  flare with the relaxation process following forced reconnection between
  the expanding CME structure and neighboring magnetic fields.

---------------------------------------------------------
Title: Decametric N Burst: A Consequence of the Interaction of Two
    Coronal Mass Ejections
Authors: Démoulin, P.; Klein, K. -L.; Goff, C. P.; van
   Driel-Gesztelyi, L.; Culhane, J. L.; Mandrini, C. H.; Matthews, S. A.;
   Harra, L. K.
2007SoPh..240..301D    Altcode:
  Radio emissions of electron beams in the solar corona and interplanetary
  space are tracers of the underlying magnetic configuration and of
  its evolution. We analyse radio observations from the Culgoora and
  WIND/WAVES spectrographs, in combination with SOHO/LASCO and SOHO/MDI
  data, to understand the origin of a type N burst originating from NOAA
  AR 10540 on January 20, 2004, and its relationship with type II and
  type III emissions. All bursts are related to the flares and the CME
  analysed in a previous paper (Goff et al., 2007). A very unusual feature
  of this event was a decametric type N burst, where a type III-like
  burst, drifting towards low frequencies (negative drift), changes drift
  first to positive, then again to negative. At metre wavelengths, i.e.,
  heliocentric distances ≲1.5R<SUB>⊙</SUB>, these bursts are ascribed
  to electron beams bouncing in a closed loop. Neither U nor N bursts are
  expected at decametric wavelengths because closed quasi-static loops
  are not thought to extend to distances ≫1.5R<SUB>⊙</SUB>. We take
  the opportunity of the good multi-instrument coverage of this event to
  analyse the origin of type N bursts in the high corona. Reconnection
  of the expanding ejecta with the magnetic structure of a previous CME,
  launched about 8 hours earlier, injects electrons in the same manner as
  with type III bursts but into open field lines having a local dip and
  apex. The latter shape was created by magnetic reconnection between
  the expanding CME and neighbouring (open) streamer field lines. This
  particular flux tube shape in the high corona, between 5R<SUB>⊙</SUB>
  and 10R<SUB>⊙</SUB>, explains the observed type N burst. Since the
  required magnetic configuration is only a transient phenomenon formed
  by reconnection, severe timing and topological constraints are present
  to form the observed decametric N burst. They are therefore expected
  to be rare features.

---------------------------------------------------------
Title: Study of CME transit speeds for the event of 07-NOV-2004
Authors: Culhane, J. L.; Pohjolainen, S.; van Driel-Gesztelyi, L.;
   Manoharan, P. K.; Elliott, H. A.
2007AdSpR..40.1807C    Altcode:
  Several methods for CME speed estimation are discussed. These include
  velocity derivation based on the frequency drifts observed in metric
  and decametric radio wave data using a range of coronal density
  models. Coronagraph height-time plots allow measurement of plane-of-sky
  and expansion speeds. These in turn can enable propagation speeds to
  be derived from a range of empirical relations. Simple geometric e.g.,
  cone, models can provide propagation velocity estimates for suitable
  halo or partial halo events. Interplanetary scintillation observations
  allow speed estimates at large distances from the Sun detecting in
  particular the deceleration of the faster CMEs. Related interplanetary
  shocks and the arrival times and speeds of the associated magnetic
  clouds at Earth can also be considered. We discuss the application of
  some of these methods to the transit to Earth of a complex CME that
  originated earlier than 16:54 U.T. on 07-NOV-2004. The difficulties
  in making velocity estimates from radio observations, particularly
  under disturbed coronal conditions, are highlighted.

---------------------------------------------------------
Title: Magnetic coupling of the Sun Earth system   The view from
    STEREO
Authors: Matthews, S. A.; Culhane, J. L.
2007AdSpR..39.1791M    Altcode:
  The STEREO mission, launched on October 25 2006, will provide the first
  stereoscopic view of the Sun and its magnetic environment. A suite of
  identical instruments on two continuously separating spacecraft will
  monitor the onset of solar eruptive phenomena, and track them as the
  shocks and ejected material propagate through the interplanetary medium
  (IPM). The combination of remote sensing and in situ instrumentation
  will provide new insights into the onset of eruptions, the extent of
  their effects on the global structure of the low corona, and their
  subsequent evolution through the IPM. These observations will provide
  new constraints on the processes involved and allow us to distinguish
  between competing models of eruptive solar phenomena.

---------------------------------------------------------
Title: Build-up of a CME and its Interaction with Large-Scale
    Magnetic Structures
Authors: van Driel-Gesztelyi, L.; Goff, C. P.; Demoulin, P.; Culhane,
   J. L.; Klein, K. L.; Mandrini, C. H.; Matthews, S. A.; Harra, K. L.;
   Kurokawa, H.
2006IAUJD...3E..86V    Altcode:
  Introduction: A series of flares (GOES class M, M and C) and a
  CME were observed on 20-JAN-2004 occurring in close succession in
  NOAA 10540. Types II, III and a N radio bursts were associated. We
  investigate the link between the flares (two impulsive flares followed
  by an LDE) and the CME as well as the origin of the rare decametric
  N-burst. Methods: We use the combined observations from TRACE, SOHO/EIT,
  H-alpha images from Kwasan Observatory, SOHO/MDI magnetograms, GOES
  and radio observations from Culgoora and Wind/WAVES as well as magnetic
  modelling to understand the complex development of this event. Results:
  We link the first two impulsive flares to tether-cutting reconnections
  and the launch of the CME, while the last of the flares, an LDE,
  to the relaxation phase following forced reconnections between the
  erupting flux rope and neighbouring magnetic field lines. We show
  that reconnection with the magnetic structure of a previous CME,
  launched about 8 hours earlier, injects electrons into open field
  lines having a local dip and apex of about 6 solar radii height. The
  dipped shape of these field lines was due to large-scale magnetic
  reconnection between expanding magnetic loops and open field lines of a
  neighbouring streamer. This particular situation explains the observed
  decametric N burst. Discussion: This complex observation shows that
  impulsive quadrupolar flares can be eruptive, while an LDE may remain
  a confined event. We find that reconnection forced by the expanding CME
  structure is followed by a relaxation phase, when reconnection reverses
  and restores some of the pre-eruption magnetic connectivities. The
  observed decametric N-burst was caused by the interaction of two CMEs
  and reconnection of their expanding magnetic field with neighbouring
  streamer field lines - a very particular interplay, which explains
  why N-bursts are so rare.

---------------------------------------------------------
Title: The extreme UV imaging spectrometer for the JAXA Solar-B
    mission
Authors: Culhane, J. L.; Doschek, G. A.; Watanabe, T.; Smith, A.;
   Brown, C.; Hara, H.; Harra, L. K.; James, A. M.; al Janabi, K.;
   Kent, B.; Korendyke, C.; Lang, J.; Mariska, J.; Myers, S.; Seely,
   J.; Simnett, G.; Tandy, J.; Thomas, R.; Windt, D. L.
2006SPIE.6266E..0TC    Altcode: 2006SPIE.6266E..22C
  The ISAS/JAXA Solar-B mission includes an Extreme-UV Imaging
  Spectrometer (EIS). It detects photons in the wavelength ranges 17 -
  21 nm and 25 - 29 nm which include emission lines from several highly
  ionised species that exist at temperatures log T = 4.7, 5.6, 5.8,
  5.9 and 6.0 - 7.3 K. Instrument throughput is increased substantially
  by the use of multilayer coatings optimized for maximum reflectance
  in the two selected wavelength bands. The use of back-illuminated
  CCDs provides significantly enhanced quantum efficiency over that
  previously available from microchannel plate systems. In this paper we
  will describe the design and operation of the instrument and present
  its performance parameters e.g. spectral and spatial resolution and
  sensitivity. Preliminary results of recent calibration measurements
  will be described. The role of EIS in the Solar-B mission will be
  illustrated with reference to the anticipated observing strategy for
  the first three months of the mission which will be outlined.

---------------------------------------------------------
Title: The Extreme Ultraviolet Imaging Spectrometer (EIS) on Solar-B
Authors: Doschek, George A.; Brown, C. M.; Korendyke, C. M.; Mariska,
   J. T.; Myers, S. H.; Seely, J. F.; Dere, K. P.; Lang, J.; Culhane,
   J. L.; Watanabe, T.
2006SPD....37.3604D    Altcode: 2006BAAS...38S.260D
  The Extreme Ultraviolet Imaging Spectrometer (EIS) for Solar-B is a
  high throughput state-of-the-art instrument designed to obtain solar
  spectra and images in two wavelength bands centered near 195 and 270
  Angstroms. Traditional spectra can be obtained using narrow slits or
  images of solar structures can be obtained in individual spectral
  lines using wide slots. Essentially, the instrument obtains images
  in wavebands similar to TRACE but in each spectral line within the
  waveband. This removes electron temperature ambiguities inherent in
  broadband imagers and allows dynamic effects to be detected via Doppler
  shifts and densities and other plasma parameters to be measured via
  spectroscopic plasma diagnostics. After a brief description of how
  the instrument works and a comparison with previous instrumentation
  (sensitivity, etc.), the presentation will focus on the science that
  can be accomplished with EIS, presented in the form of sample observing
  sequences. The focus will be on active regions and solar flares with a
  consideration of topics such as temperature and density distributions
  in active region loops and their evolution, dynamical motions in active
  region loops, the reconnection site in solar flares, and temperature
  evolution of multimillion degree flare loops.

---------------------------------------------------------
Title: Non-thermal broadening of coronal emission lines in the onset
    phase of solar flares and CMEs
Authors: Kay, H. R. M.; Matthews, S. A.; Harra, L. K.; Culhane, J. L.
2006A&A...447..719K    Altcode:
  The non-thermal broadening of soft X-ray emission lines is commonly seen
  during the early stages of solar flares and is thought to be associated
  with either the initial flare energy release or the evaporation of
  chromospheric plasma. Here we investigate the magnitude of non-thermal
  broadening for a sample of 12 flares associated with both eruptive and
  non-eruptive events, i.e. those with and without associated coronal mass
  ejections (CMEs), using the Bragg Crystal Spectrometer (BCS) on the
  Yohkoh spacecraft. The maximum non-thermal broadening of the eruptive
  flares was found to be on average lower than for the flares which were
  not associated with CMEs. There was no evidence of any relationship
  between the maximum non-thermal broadening and the initial CME speed.

---------------------------------------------------------
Title: Lines in the range 3.2 6.1 Å observed in RESIK spectra
Authors: Sylwester, B.; Sylwester, J.; Siarkowski, M.; Phillips,
   K. J. H.; Culhane, J. L.; Lang, J.; Brown, C.; Kuznetsov, V. D.
2006AdSpR..38.1534S    Altcode:
  RESIK is a Bragg bent crystal X-ray spectrometer on board the CORONAS-F
  satellite. Between 24 August 2002 and 22 May 2003 RESIK collected
  a large number of solar X-ray spectra in four energy bands covering
  the range 3.2 6.1 Å. A recent absolute calibration has allowed us to
  make detailed identification of observed spectral features, and from
  observed line and continuum fluxes to get temperature, emission measure,
  etc. The lines were identified using spectra averaged over periods of
  various solar activity levels. These averaged spectra contain a number
  of strong lines with transitions in H- and He-like ions of K, Ar, S
  and Si. Some of them are resonance parent lines and their satellites
  which were observed with other spectrometers and have been described
  elsewhere. Here, we report detection of several lines not previously
  observed in solar spectra, including lines of H-like and He-like S
  and Si ions with transitions 1s np and 1s<SUP>2</SUP> 1snp, n up to
  10. In addition we provide identification of the He-like Cl (Cl XVI)
  triplet in the range 4.43 4.45 Å. The feature at 4.182 Å, which is
  the wavelength of the H-like Cl (Cl XVII) Lyα line, is probably a
  blend of S XIV satellites from cooler plasma.

---------------------------------------------------------
Title: Temperature-sensitive line ratio diagnostics based on Si
    satellite-to-resonance line ratios for 1s<SUP>2</SUP> 1snp transitions
Authors: Phillips, K. J. H.; Dubau, J.; Sylwester, J.; Sylwester,
   B.; Culhane, J. L.; Doschek, G. A.; Lang, J.
2006AdSpR..38.1543P    Altcode:
  Dielectronic satellite lines due to 1s<SUP>2</SUP>n‧l‧ 1snpn‧l‧
  (n = 3, 4) transitions in Li-like Si (Si XII) occur at 5.818 and
  5.565 Å, on the long wavelength side of the He-like Si (Si XIII)
  1s<SUP>2</SUP> 1s3p and 1s<SUP>2</SUP> 1s4p lines at 5.681 and 5.384 Å,
  respectively. They have been extensively observed with the RESIK crystal
  spectrometer on the Russian spacecraft CORONAS-F. As with corresponding
  satellites 1s<SUP>2</SUP>nl 1s2pnl on the long-wavelength side of
  the Si XIII 1s<SUP>2</SUP> 1s2p resonance line, there is an inverse
  temperature dependence of the intensity ratio of the satellites to the
  He-like ion lines (I<SUB>sat</SUB>/I<SUB>He</SUB>). New atomic data
  are used to calculate the Si XII satellite line intensities and thus
  the I<SUB>sat</SUB>/I<SUB>He</SUB> ratio. RESIK observations of the
  ratio in solar flares, together with temperatures from the ratio of
  the two GOES X-ray channels, are compared with theoretical variation
  of the ratio with temperature. The good agreement indicates this to
  be a valuable temperature diagnostic for solar flares and laboratory
  plasmas such as tokamaks. There are implications for similar satellites
  in Fe line spectra which are observed with broad-band resolution by
  the RHESSI solar flare mission.

---------------------------------------------------------
Title: Multi-scale reconnections in a complex CME
Authors: van Driel-Gesztelyi, L.; Goff, C.; Demoulin, P.; Culhane,
   J. L.; Matthews, S. A.; Harra, L. K.; Mandrini, C. H.; Klein, K. L.;
   Kurokawa, H.
2006cosp...36.2371V    Altcode: 2006cosp.meet.2371V
  A series of flares GOES class M M and C and a CME were observed on
  20-JAN-2004 occurring in close succession in NOAA 10540 Types II III
  and an N radio bursts were associated We use the combined observations
  from TRACE EIT H-alpha images from Kwasan Observatory MDI magnetograms
  GOES and radio observations from Culgoora and Wind WAVES to understand
  the complex development of this event We link the first two impulsive
  flares to tether-cutting reconnections and the launch of the CME while
  the last of the flares an LDE to the relaxation phase following forced
  reconnections between the erupting flux rope and neighbouring magnetic
  field lines We show that reconnection with the magnetic structure of
  a previous CME launched about 8 hours earlier injects electrons into
  open field lines having a local dip and apex of about 6 solar radii
  height The dipped shape of these field lines was due to large-scale
  magnetic reconnection between expanding magnetic loops and open field
  lines of a neighbouring streamer This particular situation explains
  the observed decametric N burst and why N-bursts are so rare

---------------------------------------------------------
Title: Analysis of potassium abundance in a large number of flares
Authors: Sylwester, J.; Sylwester, B.; Phillips, K. J. H.; Culhane,
   J. L.; Brown, C.; Lang, J.; Stepanov, A. I.
2006AdSpR..38.1490S    Altcode:
  An initial study of spectra observed in the shortest wavelength
  channel (3.40-3.80 Å) of the RESIK X-ray spectrometer on CORONAS-F
  indicates the presence of substantial flare-to-flare variations in
  the line-to-continuum ratio of several lines, in particular He-like
  potassium (K XVIII) lines, occurring in the range 3.53-3.57 Å. The
  observed variations are larger than those expected from temperature
  variations. This has motivated a study of possible variations in
  the potassium abundance in the observed spectra. With a new RESIK
  calibration available, we have obtained absolute fluxes of the K
  XVIII resonance line as well as the continuum and lines observed in
  other RESIK channels (3.40-6.05 Å) for some 1163 intervals observed
  early in 2003. Analysis of these observations allowed us to determine
  the average absolute potassium abundance for the period studied and
  investigate the variability of abundance. The results obtained are
  presented and discussed.

---------------------------------------------------------
Title: a Series of Compact Flares with AN Associated CME
Authors: Goff, C. P.; van Driel-Geszrelyi, L.; Culhane, J. L.;
   Matthews, S. A.; Harra, L. K.; Démoulin, P.; Mandrini, C. H.;
   Kurokawa, H.
2005ESASP.600E.157G    Altcode: 2005ESPM...11..157G; 2005dysu.confE.157G
  No abstract at ADS

---------------------------------------------------------
Title: Relating Near-Earth Observations of AN Interplanetary Coronal
    Mass Ejection to the Conditions at its Site of Origin in the Solar
    Corona
Authors: Fazakerley, A. N.; Harra, L. K.; Culhane, J. L.; van
   Driel-Gesztelyi, L.; Lucek, E.; Matthews, S. A.; Owen, C. J.; Mazelle,
   C.; Balogh, A.; Réme, H.
2005ESASP.600E..47F    Altcode: 2005dysu.confE..47F; 2005ESPM...11...47F
  No abstract at ADS

---------------------------------------------------------
Title: Flows in the solar atmosphere due to the eruptions on the
    15th July, 2002
Authors: Harra, L. K.; Démoulin, P.; Mandrini, C. H.; Matthews,
   S. A.; van Driel-Gesztelyi, L.; Culhane, J. L.; Fletcher, L.
2005A&A...438.1099H    Altcode:
  Which kind of flows are present during flares? Are they compatible
  with the present understanding of energy release and which model
  best describes the observations? We analyze successive flare events
  in order to answer these questions. The flares were observed in the
  magnetically complex NOAA active region (AR) 10030 on 15 July 2002. One
  of them is of GOES X-class. The description of these flares and how
  they relate to the break-out model is presented in Gary &amp; Moore
  (2004). The Coronal Diagnostic Spectrometer on board SOHO observed
  this active region for around 14 h. The observed emission lines
  provided data from the transition region to the corona with a field
  of view covering more than half of the active region. In this paper
  we analyse the spatially resolved flows seen in the atmosphere from
  the preflare to the flare stages. We find evidence for evaporation
  occurring before the impulsive phase. During the main phase, the
  ongoing magnetic reconnection is demonstrated by upflows located at
  the edges of the flare loops (while downflows are found in the flare
  loops themselves). We also report the impact of a filament eruption
  on the atmosphere, with flows up to 300 km s<SUP>-1</SUP> observed at
  transition-region temperatures in regions well away from the location
  of the pre-eruptive filament. Our results are consistent with the
  predictions of the break out model before the impulsive phase of the
  flare; while, as the flare progresses, the directions of the flows are
  consistent with flare models invoking evaporation followed by cooling
  and downward plasma motions in the flare loops.

---------------------------------------------------------
Title: Relating near-Earth observations of an interplanetary coronal
    mass ejection to the conditions at its site of origin in the solar
    corona
Authors: Fazakerley, A. N.; Harra, L. K.; Culhane, J. L.; van
   Driel-Gesztelyi, L.; Lucek, E.; Matthews, S. A.; Owen, C. J.; Mazelle,
   C.; Balogh, A.; Rème, H.
2005GeoRL..3213105F    Altcode:
  A halo coronal mass ejection (CME) was detected on January 20, 2004. We
  use solar remote sensing data (SOHO, Culgoora) and near-Earth in situ
  data (Cluster) to identify the CME source event and show that it was a
  long duration flare in which a magnetic flux rope was ejected, carrying
  overlying coronal arcade material along with it. We demonstrate that
  signatures of both the arcade material and the flux rope material are
  clearly identifiable in the Cluster and ACE data, indicating that the
  magnetic field orientations changed little as the material traveled
  to the Earth, and that the methods we used to infer coronal magnetic
  field configurations are effective.

---------------------------------------------------------
Title: The Extreme Ultraviolet Imaging Spectrometer on Solar-B
Authors: Mariska, J. T.; Brown, C. M.; Doschek, G. A.; Korendyke,
   C. M.; Myers, S. H.; Seely, J. F.; Dere, K. P.; Lang, J.; Culhane,
   J. L.; Watanabe, T.
2005AGUSMSP43A..02M    Altcode:
  The Extreme Ultraviolet Imaging Spectrometer (EIS) is currently under
  development for flight on the Japanese Solar-B satellite. EIS uses a
  multilayer-coated off-axis telescope mirror and a multilayer-coated
  toroidal grating spectrometer to produce stigmatic spectra of solar
  regions isolated by a 1024 arcsec high slit. The instrument produces
  monochromatic images either by rastering the solar image across a
  narrow entrance slit or by using a very wide slit. Half of each optic
  is coated to optimize reflectance at 19.5 nm, and the other half to
  optimize reflectance at 27.0 nm, with each wavelength range imaged
  onto a separate CCD detector. EIS can provide key dynamical and density
  diagnostic information. Combining EIS data with observations from the
  other instruments on Solar-B should provide a detailed picture of solar
  atmospheric processes from the visible surface into the corona. In
  this presentation, we provide details of the instrument's expected
  performance based on calibration of the individual flight optics and
  end-to-end testing at the Rutherford Appleton Laboratory in the UK.

---------------------------------------------------------
Title: Book Review: Book review
Authors: Culhane, Len
2005SpPol..21..233C    Altcode:
  For more than a decade, the UN and the European Space Agency have
  organized a series of international workshops on Basic Space Science
  to facilitate a dialogue between scientists from developing and
  industrialized nations. In an introduction consisting of five papers,
  the present book explains the background to this initiative and then
  presents, by geographical region, a selection from the topics that have
  been discussed at the workshops. Four sections, organized by region
  of the Earth (Asia/Pacific, Latin America/Caribbean, Sub-Saharan
  Africa, Western Asia/Northern Africa), contain some 25 separate
  contributions. Section 5 includes six papers on the development of
  small ground-based astronomical telescope facilities, while Section
  6 has five papers that discuss potential future projects for space
  science and astronomy in developing countries. A concluding section
  presents some eight astrophysical topics and associated problems and
  is aimed at providing material on astronomy that could conveniently
  be included in a university physics course.

---------------------------------------------------------
Title: Resik: A Bent Crystal X-ray Spectrometer for Studies of Solar
    Coronal Plasma Composition
Authors: Sylwester, J.; Gaicki, I.; Kordylewski, Z.; Kowaliński,
   M.; Nowak, S.; Płocieniak, S.; Siarkowski, M.; Sylwester, B.;
   Trzebiński, W.; Bakała, J.; Culhane, J. L.; Whyndham, M.; Bentley,
   R. D.; Guttridge, P. R.; Phillips, K. J. H.; Lang, J.; Brown, C. M.;
   Doschek, G. A.; Kuznetsov, V. D.; Oraevsky, V. N.; Stepanov, A. I.;
   Lisin, D. V.
2005SoPh..226...45S    Altcode:
  We describe the RESIK (REntgenovsky Spektrometr s Izognutymi Kristalami)
  instrument, consisting of two double-channel X-ray spectrometers,
  designed to observe solar active region and flare plasmas. RESIK is
  one of the instruments making up the scientific payload of the Russian
  CORONAS-F solar mission. The uncollimated spectrometer uses two silicon
  and two quartz bent crystals observing flare, active region and coronal
  spectra in four wavelength bands with a resolving power (λ/Δ λ)
  of ∼1000. The wavelength coverage, 3.3-6.1 Å, includes emission
  lines of Si, S, Cl, Ar, and K and in the third diffraction order,
  the wavelength range includes He-like Fe lines (1.85 Å) and Ni lines
  (1.55 Å) with dielectronic satellites, emitted during intense, hot
  flares. The instrument is believed to be the best calibrated space-borne
  crystal spectrometer flown to date. The spectrometer dynamically adjusts
  the data gathering intervals from 1 s to 5 minutes, depending on the
  level of solar X-ray emission at the time of observation. The principal
  aims of RESIK are the measurements of relative and absolute element
  abundances in the emitting plasma and the temperature distribution of
  plasma (differential emission measure) over the temperature interval 3
  and 50 MK. This paper summarizes the scientific objectives of RESIK
  and describes the design, characteristics, and performance of the
  instrument.

---------------------------------------------------------
Title: Preface
Authors: Culhane, Len; Harrison, Richard
2005AdSpR..36.1477C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The Solar-B EUV imaging spectrometer and its science goals
Authors: Culhane, J. L.; Harra, L. K.; Doschek, G. A.; Mariska, J. T.;
   Watanabe, T.; Hara, H.
2005AdSpR..36.1494C    Altcode:
  The Solar-B mission includes an Extreme-UV Imaging Spectrometer
  (EIS). It detects photons in the ranges 170-210 and 250-290 Å which
  include emission lines from several highly ionised species that exist
  at temperatures log T = 4.7, 5.6, 5.8, 5.9 and 6.0-7.3 K. In this
  paper, we will describe the design and operation of the instrument
  and present its performance parameters, e.g., spectral and spatial
  resolution and sensitivity. Preliminary results of recent calibration
  measurements will be described. Its role in the Solar-B mission will
  be illustrated with reference to several key science topics that the
  EIS is expected to address. The anticipated observing strategy for
  the first three months of the mission will be outlined.

---------------------------------------------------------
Title: X-Ray and EUV Observations of Large-Scale Coronal Structures
Authors: Culhane, J. L.; Foley, C. R.
2004ASPC..325..205C    Altcode:
  Large-scale coronal streamers, first recognized in solar eclipse images
  and in white-light coronagraph data, are now more frequently observed
  with space-borne coronagraphs e.g. LASCO on SOHO, out to a distance
  of ∼ 30 R<SUB>⊙</SUB>. The SOHO spectrometers, CDS and SUMER, have
  been used for emission line intensity studies of these structures. The
  SOHO UVCS has undertaken UV spectroscopy and visible polarimetry
  studies of the corona to a height of ∼ 12 R<SUB>⊙</SUB>. Yohkoh
  SXT observations of large coronal structures, made in the period
  before December 1992, will be discussed. Subsequent observations by
  the SOHO instruments will also be reviewed. The origin of the slow
  solar wind will be discussed. The properties of transequatorial loop
  systems will be reviewed and their relationship to coronal heating,
  CME occurrence and flaring examined. Recent work on the relationship
  between solar coronal and stellar X-ray radiance and unsigned magnetic
  flux will be briefly described.

---------------------------------------------------------
Title: Instrumentation for Photon Detection in Space
Authors: Culhane, J. L.
2004spsc.book..365C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Identification of Lines in the Range 3.35 A - 6.1 A Observed
    in RESIK Spectra
Authors: Sylwester, B.; Sylwester, J.; Siarkowski, M.; Phillips,
   K. J. H.; Culhane, J. L.; Lang, J.; Brown, C.; Kuznetsov, V. D.
2004cosp...35.2663S    Altcode: 2004cosp.meet.2663S
  RESIK is the Bragg bent crystal X-ray spectrometer on board CORONAS-F
  satellite. Between August 24, 2002 and May 22, 2003, the instrument
  collected a large database of solar X-ray spectra in four energy bands
  covering the range 3.35 Å - 6.1 Å. We have recently calibrated the
  spectra in order to determine an absolute wavelength scale and absolute
  photon fluxes. This has allowed us to make detailed indentifications
  of observed spectral features, and to interpret the observed line
  and continuum fluxes in terms of basic plasma characteristics
  like temperature and emission measure. Our line identifications
  have been made using spectra averaged over periods of various solar
  activity levels, e.g. flare rise and decay phases, non-flaring active
  regions and quiet Sun. The spectra contain a number of strong lines
  corresponding to the transitions in H- and He-like ions of K, Ar, S
  and Si. Some of these lines are resonance lines and their satellites
  which have already been noted by previous authors using data from
  other spectrometers, but several lines have never been observed in
  solar spectra before. These include lines of H-like and He-like S and
  Si corresponding to transitions 1s - np and 1s^2 -1s np with n up to
  ∼10. In addition we provide indentification of the H-like Cl (Cl
  XVII) Ly-alpha lines at 4.182 Å, and He-like Cl (Cl XVI) triplet in
  the range 4.43 Å,- 4.45 Å, never before observed simultaneously. We
  will present detailed identifications of these lines in this paper.

---------------------------------------------------------
Title: Analysis of Potassium Abundance Variability in Selected
    Solar Flares
Authors: Sylwester, J.; Sylwester, B.; Phillips, K. J. H.; Culhane,
   J. L.; Brown, C.; Lang, J.; Stepanov, A. I.
2004cosp...35.2639S    Altcode: 2004cosp.meet.2639S
  A quick-look inspection of spectra observed in the shortwavelength
  channel (3.35 Å,- 3.8 Å) of the RESIK X-ray spectrometer on Coronas-F
  indicates the presence of substantial flare-to-flare variations in
  the line-to-continuum ratio of several lines, in particular He-like
  potassium (K XVIII) lines, occurring at 3.53 Å,- 3.57 Å. The
  observed variations are larger those expected from temperature
  variations. This has motivated a detailed study of possible variations
  in the flare-to-flare potassium abundance. With newly calibrated RESIK
  spectra, we have obtained absolute fluxes of the K XVIII resonance,
  intercombination and forbidden lines as well as the continuum and
  lines observed in other RESIK channels (3.35 Å,- 6.1 Å). These
  data have allowed us to determine the absolute potassium abundance
  for a selection of flares, mostly short-lived with a range of X-ray
  importance. The results obtained are presented and discussed.

---------------------------------------------------------
Title: Temperature-sensitive Line Ratios Diagnostics of the
    non-flaring Corona based on Satellite-to-Resonance Line Ratios for
    1s^2-1s(np) Transitions
Authors: Phillips, K. J. H.; Dubau, J.; Sylwester, J.; Sylwester,
   B.; Kordylewski, Z.; Culhane, J. L.; Doschek, G. A.; Lang, J.
2004cosp...35.2579P    Altcode: 2004cosp.meet.2579P
  One of the most convenient electron temperature diagnostics of
  hot astrophysical plasmas is the intensity ratio of dielectronic
  satellite lines to resonance lines in the X-ray region. Until now,
  this diagnostic has been applied to satellites near the 1s-2p lines of
  H-like ions or the 1s^2 - 1s2p lines of He-like ions, these lines being
  extensively observed with crystal spectrometers during flares. However,
  satellites near the 1s^2 - 1snp (n&gt;2) lines of He-like ions,
  unlike those near the 1s^2 - 1s2p lines, have the important advantage
  of being well separated from their parent lines and unblended with
  other lines. Spectra from the RESIK spectrometer on Coronas-F,
  covering the wavelength range 3.4 Å,- 6.1 Å, are highly suited
  for observation of these satellites, due to transitions from the n =
  3, 4 and 5 levels to the n = 1 level, near corresponding resonance
  lines of H-like and He-like Si (Si XIII, Si XIV) and S (S XV, S XVI)
  ions. New calculations of satellite intensity factors presented in
  this paper enable temperatures to be calculated from observed ratios
  of Li-like Si (Si XII) 1s^2 2p ^2P<SUB>1/2,3/2</SUB> - 1s 2p (^3P) 3p
  ^2D<SUB>3/2,5/2</SUB> satellite complex (5.816 Å) near He-like Si (Si
  XIII) 1s^2 ^1S_0 - 1s 3p ^1P_1} resonance (5.681 Å) line. These lines
  are well observed in recent quiet and non-flaring active region RESIK
  X-ray spectra, and therefore provide the most sensitive temperature
  diagnostic tool for physical conditions in weakly active corona.

---------------------------------------------------------
Title: Solar-B EIS and its Science Goals
Authors: Culhane, J. L.; Doschek, D. A.; Watanabe, T.
2004cosp...35.4214C    Altcode: 2004cosp.meet.4214C
  The EUV Imaging Spectrometer (EIS) instrument is designed to study
  the emission line spectrum of coronal and transition region plasma in
  the wavelength range 15nm to 30nm. It will obtain information on the
  dynamics, velocity, temperature and density of the emitting plasma with
  a spatial resolution of ∼ 2 arc sec. EIS represents the next stage in
  the development of scanning imaging EUV spectrometers. It has about a
  factor ten larger effective aperture than the SOHO Coronal Diagnostic
  Spectrometer, due to the use of multilayer-coated optical elements,
  along with an even greater enhancement in wavelength resolution. In
  this paper, the EIS instrument features will be described and estimates
  given for its expected performance. In particular, the emission line
  spectra are registered with sufficient time and spatial resolution to
  allow determination of plasma dynamics and temperature as a function of
  position within solar flare and solar active region loops. Spectra will
  be accurately related in position to the images obtained by the Solar-B
  white light and X-ray telescopes. Thus the EIS science aims will be
  discussed in the context of its anticipated role in the Solar-B mission.

---------------------------------------------------------
Title: The CCD and readout electronics for the OMC instrument
    on Integral
Authors: Walton, D. M.; Thomas, P. D.; Culhane, J. L.; Jordan, B.;
   Smith, A.; Dibbens, A. P.; Bradley, L. J.
2003A&A...411L.275W    Altcode:
  The Optical Monitoring Camera (OMC) on ESA's Integral gamma-ray
  astronomy satellite is devoted to optical wavelength observations
  simultaneously covering the same field-of-view as the gamma-ray and
  X-ray instruments. The OMC consists of a refracting telescope with a
  CCD as the imaging device in the focal plane. Here we describe the
  CCD and its associated readout electronics, in particular pointing
  out features of interest to users of the OMC instrument and its data.

---------------------------------------------------------
Title: OMC: An Optical Monitoring Camera for INTEGRAL. Instrument
    description and performance
Authors: Mas-Hesse, J. M.; Giménez, A.; Culhane, J. L.; Jamar, C.;
   McBreen, B.; Torra, J.; Hudec, R.; Fabregat, J.; Meurs, E.; Swings,
   J. P.; Alcacera, M. A.; Balado, A.; Beiztegui, R.; Belenguer, T.;
   Bradley, L.; Caballero, M. D.; Cabo, P.; Defise, J. M.; Díaz, E.;
   Domingo, A.; Figueras, F.; Figueroa, I.; Hanlon, L.; Hroch, F.;
   Hudcova, V.; García, T.; Jordan, B.; Jordi, C.; Kretschmar, P.;
   Laviada, C.; March, M.; Martín, E.; Mazy, E.; Menéndez, M.; Mi,
   J. M.; de Miguel, E.; Muñoz, T.; Nolan, K.; Olmedo, R.; Plesseria,
   J. Y.; Polcar, J.; Reina, M.; Renotte, E.; Rochus, P.; Sánchez, A.;
   San Martín, J. C.; Smith, A.; Soldan, J.; Thomas, P.; Timón, V.;
   Walton, D.
2003A&A...411L.261M    Altcode:
  The Optical Monitoring Camera (OMC) will observe the optical emission
  from the prime targets of the gamma-ray instruments onboard the ESA
  mission INTEGRAL, with the support of the JEM-X monitor in the X-ray
  domain. This capability will provide invaluable diagnostic information
  on the nature and the physics of the sources over a broad wavelength
  range. Its main scientific objectives are: (1) to monitor the optical
  emission from the sources observed by the gamma- and X-ray instruments,
  measuring the time and intensity structure of the optical emission
  for comparison with variability at high energies, and (2) to provide
  the brightness and position of the optical counterpart of any gamma-
  or X-ray transient taking place within its field of view. The OMC is
  based on a refractive optics with an aperture of 50 mm focused onto
  a large format CCD (1024 x 2048 pixels) working in frame transfer
  mode (1024 x 1024 pixels imaging area). With a field of view of
  5<SUP>o</SUP>x5<SUP>o</SUP> it will be able to monitor sources down
  to magnitude V = 18. Typical observations will perform a sequence of
  different integration times, allowing for photometric uncertainties
  below 0.1 mag for objects with Vle16 .

---------------------------------------------------------
Title: SADE: The starspot and dynamo explorer
Authors: Martens, P. C. H.; Acton, L. W. A.; Klumpar, D.; Kankelborg,
   C.; Stern, R. A.; Peres, G.; Culhane, J. L.
2003AdSpR..32.1123M    Altcode:
  We propose a mission called SADE, the Starspot And Dynamo Explorer, to
  study dynamo activity in nearby late-type stars. The onboard instruments
  will be a Ca-K telescope for magnetically dominated chromospheric
  emission, and an X-ray grazing incidence telescope to study coronal
  emission. We design the mission for a life-time of 15 years or longer
  to capture a full activity cycle for most solar-type stars. We aim to
  firmly establish the spectrum of the relation between chromospheric
  and corona' emission in late-type stars, and capture one or more stars
  going into or coming out of a Maunder type minimum. Operation costs will
  be kept to a minimum by automating mission operations to a maximum,
  and have the science operations be carried out by students at Montana
  State University.

---------------------------------------------------------
Title: Patterns of X-ray line emission variability as observed by
    the RESIK Bragg spectrometer
Authors: Sylwester, J.; Sylwester, B.; Culhane, J. L.; Doschek, G. A.;
   Oraevsky, V. N.; Phillips, K. J. H.
2003ESASP.535..733S    Altcode: 2003iscs.symp..733S
  RESIK is a unique Bragg bent crystal spectrometer operating continuously
  since August 2001. By now, it has collected ~10 GB of solar flare and
  active region spectra in a very much unexplored spectral region between
  3.2 Å and 6.1 Å. In this paper we present a number of representative
  observations covering periods of various solar activity: from the most
  active level (M+ flares) to exceptionally quiet corona. We present also
  a tentative list of the spectral features observed. In the wavelength
  range observed by RESIK there are a number of strong emission lines
  corresponding to H- and He-like resonance transitions of Si, S, Ar and K
  ions. These lines are formed by thermal plasma of temperature between
  5 and 50 MK, and therefore their analysis reveal the distribution
  of hot plasma over this interval. RESIK sees lines from a number of
  different elements, so it is possible to do abundance analyses. The
  elements concerned have a wide range of first ionisation potentials
  (FIPs) so it has been possible to examine the dependence of coronal or
  flare abundances on FIP. We have observed substantial variations of
  the K/Ar line ratio, and respective line/continuum ratios, which can
  be best explained by allowing for changes in the chemical composition
  of the coronal plasma

---------------------------------------------------------
Title: Flare characteristics: Properties of eruptive and non-eruptive
    events and their associations
Authors: Kay, H. R. M.; Culhane, J. L.; Harra, L. K.; Matthews, S. A.
2003AdSpR..32.1051K    Altcode:
  The complex: relationship between solar flares and coronal mass
  ejections is investigated using a comparison of flare parameters for
  a total of 69 ejective and non-ejective flares. In the case of solar
  flares which do not show mass ejection there seems to be a clear
  relationship between the peak intensity and duration, with higher
  intensity events being of longer duration. Systematic differences in
  the relationship between peak temperature and intensity for the two
  types of events are also evident, with flares accompanied by CMEs
  tending to have lower peak temperatures than non-ejective events of
  the same intensity. Whilst there appears to be a clear relationship
  between the length of rise and decay phase in a flare, there are
  no systematic differences in the parameters between ejective and
  non-ejective flares. A total of eleven EIT waves were found, all of
  which were associated with CMEs. There is no apparent correlation
  between the occurrence of an EIT wave and the peak intensity or rise
  time of the associated flare.

---------------------------------------------------------
Title: Expected Performance of the Extreme Ultraviolet Imaging
    Spectrometer on Solar-B
Authors: Mariska, J. T.; Brown, C. M.; Dere, K. P.; Doschek, G. A.;
   Korendyke, C. M.; Myers, S. H.; Seely, J. F.; Culhane, J. L.;
   Watanabe, T.
2003SPD....34.2006M    Altcode: 2003BAAS...35..845M
  The Extreme Ultraviolet Imaging Spectrometer (EIS) is currently under
  development for flight on the Japanese Solar-B satellite. EIS uses a
  multilayer-coated off-axis telescope mirror and a multilayer-coated
  toroidal grating spectrometer to produce stigmatic spectra of solar
  regions isolated by a 1024 arcsec high slit. The instrument produces
  monochromatic images either by rastering the solar image across a
  narrow entrance slit or by using a very wide slit. Half of each optic
  is coated to optimize reflectance at 19.5 nm, and the other half to
  optimize reflectance at 27.0 nm, with each wavelength range imaged
  onto a separate CCD detector. <P />In this presentation we provide an
  update on the EIS hardware development and show details of the expected
  performance of the instrument in solar quiet regions, active regions,
  and flares.

---------------------------------------------------------
Title: The soft X-ray characteristics of solar flares, both with
    and without associated CMEs
Authors: Kay, H. R. M.; Harra, L. K.; Matthews, S. A.; Culhane, J. L.;
   Green, L. M.
2003A&A...400..779K    Altcode:
  The complex relationship between solar flares and coronal mass ejections
  is investigated using a comparison of flare parameters for a total
  of 69 ejective and non-ejective flares. In the case of solar flares
  which do not show mass ejection there seems to be a clear relationship
  between the peak intensity and duration, with higher intensity events
  being of longer duration. Systematic differences in the relationship
  between peak temperature and intensity for the two types of event are
  also evident, with flares associated with CMEs tending to have lower
  peak temperatures than non-ejective events of the same intensity. Whilst
  there appears to be a clear relationship between the length of rise and
  decay phase in a flare, there are no systematic differences in these
  parameters for ejective and non-ejective flares. A total of eleven
  “EIT waves” were found, all of which were associated with CMEs. There
  is no apparent correlation between the occurrence of an EIT wave and
  the peak temperature, intensity or rise time of the associated flare.

---------------------------------------------------------
Title: Evidence for a Flux Rope driven EUV wave and CME: Comparison
    with the Piston Shock Model
Authors: Foley, C. R.; Harra, L. K.; Matthews, S. A.; Culhane, J. L.;
   Kitai, R.
2003A&A...399..749F    Altcode:
  This paper examines the relationship between a coronal wave, filament
  eruption, flare and Coronal Mass Ejection (CME) which occurred on
  2001, April 10th. We study the pre-flare activity which includes the
  eruption of a filament and a coronal wave. A large X-ray flare and
  a CME follow. We discuss how these phenomena are related and compare
  our results to recent models. These are found to be largely consistent
  with the numerical simulations of a flux rope driven CME as presented
  recently in Chen et al. (2002).

---------------------------------------------------------
Title: Introduction
Authors: Culhane, J. L.; Hunt, J. C. R.; Coates, A. J.
2003RSPTA.361....5C    Altcode:
  The space environment is currently of intense interest as the subject
  of multidisciplinary studies in science, applications and engineering,
  including the remote observation of the Earth and planets, probing
  the Sun-Earth connection, studying the Earth's environment from space,
  hazard warning and forecasting and exploring the underlying space and
  spacecraft technologies. There are natural connections between these
  areas in terms of the scientific techniques and the space technology
  required. Some of the connections are only now being discovered and
  exploited, and this conference, held at The Royal Society on 16-18
  October 2001, provided a timely focus for pursuing these further and
  identifying others.

---------------------------------------------------------
Title: Multi-wavelength observations of the pre-cursor phase of
    solar flares
Authors: Matthews, S. A.; Harra, L. K.; Culhane, J. L.
2003AdSpR..32.2553M    Altcode:
  Observational studies of the pre-cursor phase of solar flares have
  shown that there are many and varied signatures that may or may not
  indicate the probable onset of a flare. Combining data from Yohkoh,
  SOHO and TRACE and more recent observations from RHESSI, SOHO and TRACE
  we, investigate the relationships between the different manifestations
  of pre-flare behaviour in two solar flares with a view to determining
  how they are related to the subsequent flare energy release. We find
  that in one case the preflare activity seems strongly related to the
  subsequent flare and probably represents a build-up of energy in the
  active region prior to flare onset. The second case we find to be less
  clear cut suggesting that significant further work remains to be done
  in order to determine which pre-flare signatures are most useful in
  indicating the build-up to flare onset.

---------------------------------------------------------
Title: The Coronal Emission of Photospheric Magnetic Fragments
Authors: McDonald, L.; Culhane, J. L.; Matthews, S. A.; Harra, L. K.
2002SoPh..211..125M    Altcode:
  This paper examines the relationship between magnetic dipoles in the
  photosphere and X-ray bright points (XBPs) in the corona, using an XBP
  special campaign dataset obtained by the Yohkoh SXT and the NSO/Kitt
  Peak magnetograph. We find that for the cases where a simple dipole
  exists in the photosphere, the condition that they are separated by a
  distance less than the interaction distance defined by Longcope1998 is
  favorable for an XBP to be observed. For the cases where the magnetic
  topology is more complicated due to the addition of an extra fragment,
  we find that the geometry of the magnetic fragments is a major factor
  that determines if an XBP is observed. XBPs are more likely to be formed
  above magnetic fragments arranged in such a way that photospheric
  motions giving rise to reconnection between any two fragments will
  also give rise to reconnection with the remaining fragment.

---------------------------------------------------------
Title: RESIK observations of highly ionized argon and potassium
    X-ray emission lines in solar flares
Authors: Sylwester, J.; Culhane, J. L.; Doschek, G. A.; Oraevsky,
   V. N.; Phillips, K. J. H.; Sylwester, B.
2002ESASP.506..765S    Altcode: 2002svco.conf..765S; 2002ESPM...10..765S
  The first detailed solar X-ray spectra obtained by the RESIK bent
  crystal spectrometer aboard the CORONAS-F obervatory are presented
  and instrument performance discussed. RESIK is a bent crystal
  spectrometer covering four soft X-ray spectral ranges (3.369-3.879 Å,
  3.821-4.326 Å, 4.307-4.890 Å 4.960-6.086 Å), some of which have
  not been well covered by previous instruments. RESIK forms spectra
  in each of these ranges in 250 bins simultaneously in intervals
  of 10 s or so. Many flares, including several of GOES X-class,
  and bright active regions have now been observed in detail. (See
  http://www.cbk.pan.wroc.pl/2002.htm for examples.) In this paper,
  observations of spectral lines due to K XVIII, Ar XVIII, Ar XVII, S XV,
  Si XIV and Si XIII ions will be shown and the time evolution of their
  intensities will be discussed. These observations will eventually
  allow for precise determination of differential emission measure
  (DEM) and chemical composition of the hot flare plasma, and should,
  alongside data from the RHESSI, TRACE, and SOHO spacecraft, enable
  new and detailed insight into solar flare mechanisms.

---------------------------------------------------------
Title: The Magnetic Helicity Budget of a cme-Prolific Active Region
Authors: Green, L. M.; López fuentes, M. C.; Mandrini, C. H.;
   Démoulin, P.; Van Driel-Gesztelyi, L.; Culhane, J. L.
2002SoPh..208...43G    Altcode:
  Coronal mass ejections (CMEs) are thought to be the way by which the
  solar corona expels accumulated magnetic helicity which is injected
  into the corona via several methods. DeVore (2000) suggests that a
  significant quantity is injected by the action of differential rotation,
  however Démoulin et al. (2002b), based on the study of a simple bipolar
  active region, show that this may not be the case. This paper studies
  the magnetic helicity evolution in an active region (NOAA 8100) in
  which the main photospheric polarities rotate around each other during
  five Carrington rotations. As a result of this changing orientation of
  the bipole, the helicity injection by differential rotation is not a
  monotonic function of time. Instead, it experiences a maximum and even
  a change of sign. In this particular active region, both differential
  rotation and localized shearing motions are actually depleting the
  coronal helicity instead of building it. During this period of five
  solar rotations, a high number of CMEs (35 observed, 65 estimated)
  erupted from the active region and the helicity carried away has
  been calculated, assuming that each can be modeled by a twisted flux
  rope. It is found that the helicity injected by differential rotation
  (≈−7×10<SUP>42</SUP> Mx<SUP>2</SUP>) into the active region cannot
  provide the amount of helicity ejected via CMEs, which is a factor 5
  to 46 larger and of the opposite sign. Instead, it is proposed that
  the ejected helicity is provided by the twist in the sub-photospheric
  part of the magnetic flux tube forming the active region.

---------------------------------------------------------
Title: Solar cycle variation of the temperature structure within
    the cores of coronal streamers
Authors: Culhane, J. L.; Foley, C. R.; Patsourakos, S.; Mackay, D.
2002ESASP.508..371C    Altcode: 2002soho...11..371C
  We use the Coronal Diagnostic Spectrometer onboard the Solar and
  Heliospheric Observatory (SOHO) to analyze conditions in coronal
  streamer structures observed close to solar minimum (1996, July 8) and
  near maximum (1999, August 5). From emission line intensities (Fe IX-XV
  ions), the line ratio method gives the radial temperature behaviour. The
  solar minimum peak values were about 1.4 MK at 1.3 R<SUB>0</SUB>, while
  near solar maximum values were consistent with Yohkoh observations at
  the last maximum, displaying an asymptotic temperature of around 2.2
  MK above 1.2 R<SUB>0</SUB>. We discuss the observations in relation to
  possible mechanisms for energy deposition in large coronal structures.

---------------------------------------------------------
Title: Multi-wavelength observations of an X-class flare without a
    coronal mass ejection.
Authors: Green, L. M.; Matthews, S. A.; van Driel-Gesztelyi, L.;
   Harra, L. K.; Culhane, J. L.
2002SoPh..205..325G    Altcode:
  Developments in our knowledge of coronal mass ejections (CMEs) have
  shown that many of these transients occur in association with solar
  flares. On the occasions when there is a common occurrence of the
  eruption and the flare, it is most likely that the flare is of high
  intensity and/or long-duration (Burkepile, Hundhausen, and Webb,
  1994; Munro et al., 1979; Webb and Hundhausen, 1987). A model for
  the relationship between the long-duration event and eruption has
  been developed (Carmichael, 1964; Sturrock, 1966; Hirayama, 1974;
  Kopp and Pneuman, 1976), but not so for the high-intensity flares and
  eruptions. This work investigates the magnetic topology changes that
  occur for a X1.2 GOES classification flare which has no associated
  CME. It is found that the flare is likely to result from the interaction
  between two pre-existing loops low in the corona, producing a confined
  flare. Slightly higher in the corona, a loop is observed which
  exhibits an outward motion as a result of the reconfiguration during
  reconnection. The objective of this work is to gain insight on the
  magnetic topology of the event which is critical in order to determine
  whether a high-intensity flare is likely to be related to a CME or not.

---------------------------------------------------------
Title: Trajectories of microwave prominence eruptions
Authors: Hori, K.; Culhane, J. L.
2002A&A...382..666H    Altcode:
  On the basis of 17 GHz microwave images from the Nobeyama
  Radioheliograph near solar maximum (1999-2000), we examined trajectories
  of 50 prominence eruptions in order to address how prominence motions
  affect or reflect the surrounding coronal structures. We marked the
  heliocentric latitude of the top of the moving prominences on the
  white-light synoptic maps, which were constructed at 2.5-4.5 solar
  radii from the LASCO C2 coronagraph on the SOHO spacecraft. We found
  that i) 92% of the prominence eruptions were associated with coronal
  mass ejections (CMEs) and that the remaining 8% show weak mass motions
  confined to nearby streamers, and ii) coronal mass motions involving
  prominence eruptions and CMEs are not random but are organized
  by bundles of streamers. Our findings support the idea of multiple
  plasma sheets emanating from active regions, arcades, trans-equatorial
  interconnecting loops, and polar crown filaments, through which coronal
  mass is transported toward interplanetary space. This study suggests
  that microwave observations can provide useful information on the
  activity at the base of such “coronal mass corridors”.

---------------------------------------------------------
Title: What are the Origins of Quiescent Coronal Soft X-Rays?
Authors: Foley, C. R.; Culhane, J. L.; Patsourakos, S.; Yurow, R.;
   Moroney, C.; Mackay, D.
2002mwoc.conf..341F    Altcode:
  We have examined the evolution and modulation of the Sun's atmosphere
  from the photosphere up to the outer corona through the decline and
  rise of solar cycles 22, and 23 respectfully. For this we have used
  Yohkoh soft X-ray telescope (SXT) images, Kitt peak magnetograms and EUV
  spectra provided by the Coronal Diagnostic Spectrometer (CDS). We find
  as Hara (1996, 1997) found, that there is a modulation of the coronal
  brightness which varies annually in the high latitude activity zones,
  and that this is linked to the presence and disappearance of active
  regions on the sun's disk. We interpret our results with regards to the
  emergence and diffusion of magnetic flux. We find that the appearance
  of high latitude activity zones may be explained simply by the decay
  of diffused active region flux, We also find evidence for a positive
  temperature gradient within the corona from the emission profiles in
  the different lines.

---------------------------------------------------------
Title: Observations of the White Dwarf G191-B2B with a High Resolution
    EUV Spectrometer
Authors: Cruddace, R. G.; Kowalski, M. P.; Yentis, D. J.; Fritz, G. G.;
   Gursky, H.; Barstow, M. A.; Bannister, N. P.; Fraser, G. W.; Spragg,
   J. E.; Lapington, J. S.; Tandy, J. A.; Sanderson, B.; Culhane, J. L.;
   Barbee, T. W.; Kordas, J. F.; Goldstein, W.
2002ASPC..264...38C    Altcode: 2002ccea.conf...38C
  No abstract at ADS

---------------------------------------------------------
Title: High-Resolution Spectroscopy of G191-B2B in the
    Extreme-Ultraviolet
Authors: Cruddace, R. G.; Kowalski, M. P.; Yentis, D.; Brown, C. M.;
   Gursky, H.; Barstow, M. A.; Bannister, N. P.; Fraser, G. W.; Spragg,
   J. E.; Lapington, J. S.; Tandy, J. A.; Sanderson, B.; Culhane, J. L.;
   Barbee, T. W.; Kordas, J. F.; Goldstein, W.; Fritz, G. G.
2002ApJ...565L..47C    Altcode: 2001astro.ph.12254C
  We report a high-resolution (R=3000-4000) spectroscopic observation of
  the DA white dwarf G191-B2B in the extreme-ultraviolet band 220-245
  Å. A low-density, ionized He component is clearly present along
  the line of sight, which if completely interstellar implies a He
  ionization fraction considerably higher than is typical of the local
  interstellar medium. However, some of this material may be associated
  with circumstellar gas, which has been detected by analysis of the C
  IV absorption-line doublet in a Hubble Space Telescope/Space Telescope
  Imaging Spectrograph spectrum. A stellar atmosphere model assuming a
  uniform element distribution yields a best fit to the data that includes
  a significant abundance of photospheric He. The 99% confidence contour
  for the fit parameters excludes solutions in which photospheric He
  is absent, but this result needs to be tested using models allowing
  abundance gradients.

---------------------------------------------------------
Title: Trajectories of Microwave Prominence Eruptions
Authors: Hori, K.; Culhane, J. L.
2002mwoc.conf..305H    Altcode:
  We examine the trajectories of 50 prominence eruptions observed in
  microwave continuum emission near solar maximum (1999-2000). On the
  basis of Nobeyama Radioheliograph 17 GHz images, we address two major
  questions; i) what triggers the prominence activity, and ii) how
  does the prominence motion affect or reflect the surrounding coronal
  structures. We found that most prominence activity is related to some
  weak energy release (or heating) taking place in the lower corona as
  suggested by the increase of the brightness temperature. By combining
  the 17 GHz prominence images with white-light synoptic maps from the
  LASCO C2 coronagraph on the SOHO spacecraft, we verify that 94% of
  the prominence eruptions were associated with coronal mass ejections
  (CMEs) and that the remaining 6% show weak mass motions confined to
  streamers. We confirm that coronal mass motions involving prominence
  eruptions and CMEs are not random but are organized by bundles of
  streamers. The large scale evolution of coronal features within 4.5
  solar radii suggests that streamers are a signature of multiple plasma
  sheets emanating from active region belts, arcades, trans-equatorial
  interconnecting loops, and polar crown filaments, through which
  coronal mass is transported toward interplanetary space. This implies
  that magnetic forces exerted by streamers (or plasma sheets) play an
  important role in driving transient mass motions away from the Sun,
  against solar gravity.

---------------------------------------------------------
Title: Solar cycle variation of the temperature structure within
    the cores of coronal streamers
Authors: Foley, C. R.; Patsourakos, S.; Culhane, J. L.; MacKay, D.
2002A&A...381.1049F    Altcode:
  We use the Coronal Diagnostic Spectrometer onboard the Solar and
  Heliospheric Observatory (SOHO) to analyze conditions in coronal
  streamer structures observed close to solar minimum (1996 July 8)
  and near maximum (1999 August 5). We measured the intensities of
  emission lines from Fe IX-XV ions and found the most intense emission
  to be from Fe XI at solar minimum and from Fe XV at solar maximum. We
  then used the line ratio method with transitions in selected ions to
  extract the radial temperature behavior in the structures. The solar
  minimum peak values were about 1.4 MK at 1.3 R<SUB>sun</SUB>, while
  values derived close to solar maximum were consistent with the Yohkoh
  observations at the last maximum, displaying an apparently asymptotic
  temperature of around 2.2 MK above 1.2 R<SUB>sun</SUB>. We discuss the
  observations in relation to possible mechanisms for energy deposition
  in large coronal structures at different phases of the solar cycle.

---------------------------------------------------------
Title: The EUV Imaging Spectrometer and its Role in the Solar-B
    Mission
Authors: Culhane, J. L.; Doschek, G. A.; Watanabe, T.; Lang, J.
2002ISSIR...2..327C    Altcode: 2002rcs..conf..327C; 2002ESASR...2..327C
  Given the importance of the SOHO EUV instrument calibration techniques
  for the Japan/US/UK Solar-B mission, the nature of Solar-B is briefly
  described and the three scientific instruments on board the spacecraft
  are discussed. The EUV Imaging Spectrometer (EIS) instrument is
  described in some detail since it is anticipated that the SOHO
  calibration techniques will have direct application to the absolute
  calibration of EIS. The key scientific aims of Solar-B are presented.

---------------------------------------------------------
Title: Anatomy of a Flare and Coronal Mass Ejection
Authors: Foley, C. R.; Harra, L. K.; Culhane, J. L.; Mason, K. O.;
   Hori, K.; Matthews, S. A.; Iles, R. H. A.
2002mwoc.conf..253F    Altcode:
  In this paper we present the observations of a flare, CME and their
  interaction obtained with the SOHO, Trace, and Yohkoh spacecraft. More
  specifically we show evidence for wave-like motions in the Trace 171
  observations, of comparable speed to those usually inferred from EIT
  observations and thus termed `EIT waves'. We find that these waves
  commence at the same time at which a prominence is observed to rise
  within the active region and signifies the start of a gradual coronal
  mass ejection. The prominence is observed with the Coronal Diagnostic
  Spectrometer, on SOHO, with red and blueshifts which can only be
  reconciled if the structure is rotating close to the plane of the
  image with an angle of ~ 72<SUP>o</SUP>, to line of sight. During,
  the impulsive phase of the flare the prominence and CME is observed
  to accelerate from 190km/s to 900km/s.

---------------------------------------------------------
Title: The timing of non-thermal soft X-ray emission line broadenings
    in solar flares
Authors: Ranns, N. D. R.; Harra, L. K.; Matthews, S. A.; Culhane, J. L.
2001A&A...379..616R    Altcode:
  We study 59 solar limb flares using the Bragg Crystal Spectrometer
  (BCS) on Yohkoh and the Burst and Transient Source Experiment (BATSE)
  to investigate the relative timings between the Hard X-Ray (HXR)
  emission and the observed non-thermal broadenings of X-ray emission
  lines (V<SUB>nt</SUB>). We show that the duration of the HXR flux
  rise to maximum emission affects the relative timing of the main
  V<SUB>nt</SUB> peak with respect to the main HXR peak. In ~20% of the
  flares studied, secondary peaks in V<SUB>nt</SUB> are observed. These
  are always associated with a strong HXR pulse and usually occur after
  the associated HXR pulse. There are also flares that show a relationship
  between the decay times of V<SUB>nt</SUB> and HXR flux. These results
  are conducive to a causal relationship between the HXR flux and
  V<SUB>nt</SUB>. We divided the sample of flares into two classes,
  gradual rise and impulsive rise, depending on the shape of the HXR
  lightcurve up to maximum emission. We show that the V<SUB>nt</SUB>
  behaviour differs in the two classes. The implications are discussed
  with a view to understanding the mechanism of V<SUB>nt</SUB> generation.

---------------------------------------------------------
Title: Long term evolution of a non-active region sigmoid and its
    CME activity
Authors: Glover, A.; Harra, L. K.; Matthews, S. A.; Hori, K.; Culhane,
   J. L.
2001A&A...378..239G    Altcode:
  Recent studies have considered sigmoidal features in the Solar corona to
  possess a high probability of eruption. Unlike these studies which have
  focussed only on active region sigmoids, the present work centres on
  a large area which developed S-like morphology unconfined by a single
  active region. The S-like feature formed near the central meridian
  on 8th May 2000 and was observed to erupt, with an associated CME,
  twice over a period of 3 days. We observe considerable CME and flaring
  activity in two previous rotations, consistent with the observation
  of active regions and emerging flux. We illustrate sigmoid formation
  through the appearance of highly sheared soft X-ray loops overlying
  an extended filament channel. This arises from the gradual diffusion
  of flux associated with a large, dispersing active region over the
  period of three solar rotations. This scenario is indicative of shear
  build-up within the region over several rotations. The observed CMEs act
  to remove helicity from the highly sheared sigmoidal feature, finally
  producing an approximately potential filament channel on 10th May 2000.

---------------------------------------------------------
Title: Magnetic field configurations and the likelihood of coronal
    mass ejections
Authors: Culhane, J. L.; Glover, A.; Green, L. M.; Harra, L. K.;
   Matthews, S. A.; Hori, K.
2001ESASP.493..193C    Altcode: 2001sefs.work..193C
  No abstract at ADS

---------------------------------------------------------
Title: Coronal heating in the Sun and late-type stars
Authors: Harra, L. K.; Culhane, J. L.
2001Obs...121..217H    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Coronal mass ejections and their association to active
    region flaring.
Authors: Green, L. M.; Harra, L. K.; Matthews, S. A.; Culhane, J. L.
2001SoPh..200..189G    Altcode:
  Since the discovery of coronal mass ejections (CMEs), flaring has been
  thought to be associated in some way with the ejection in either cause
  or effect. When CMEs were first discovered in the 1970s it was suggested
  that they were powered by solar flares (e.g., Dryer, 1982). Research
  since then (Harrison, 1986) has indicated that there is an associated
  flare that occurs shortly after the CME. To investigate this further,
  and making no assumption that a particular flare is causally connected
  to the CME, flaring activity in nine active regions that show one or
  more CME signatures has been studied for several hours before and after
  CME launch. Although the initiation of the CME may occur on size scales
  larger than the active region itself, definite changes are seen in
  the flaring activity which may be related to the ejection. This work
  indicates that the energy released from the active region magnetic
  field via flaring is greater prior to the CME launch than after.

---------------------------------------------------------
Title: The Extreme Ultraviolet Imaging Spectrometer on Solar-B
Authors: Mariska, J. T.; Brown, C. M.; Dere, K. P.; Doschek, G. A.;
   Korendyke, C. M.; Culhane, J. L.; Watanabe, T.
2001AGUSM..SH41A12M    Altcode:
  Emission lines in the extreme ultraviolet spectral region provide a
  sensitive probe of the high-temperature plasma in the solar transition
  region and corona. Simultaneously achieving high spatial, spectral, and
  temporal resolution in this wavelength region has been challenging. We
  describe the design and capabilities of the Extreme Ultraviolet
  Imaging Spectrometer (EIS) planned for flight on the Japanese Solar-B
  satellite. EIS consists of a multilayer-coated off-axis telescope
  mirror and a multilayer-coated toroidal grating spectrometer. The
  telescope mirror forms a solar image on the spectrometer entrance slit
  assembly and the spectrometer forms stigmatic spectra of the solar
  region isolated by the 1024 arcsec high slit. The instrument includes
  thin-film aluminum filters to reject longer wavelength radiation and
  CCD detectors at the focal plane. Articulation of the primary mirror
  provides roughly 1600 arcsec of east-west coarse pointing freedom
  and 360 arcsec of fine east-west motion for rastering. Monochromatic
  images are formed either by rastering the solar image across a narrow
  entrance slit or by using a very wide slit. Half of each optic is
  coated to optimize reflectance at 19.5 nm, and the other half to
  optimize reflectance at 27.0 nm. Each wavelength range is imaged onto
  a separate CCD detector. The EIS spectral range contains emission lines
  formed over a temperature range from roughly 0.1 to 20 MK. Bright lines
  in the selected wavelength bands will yield precision measurements of
  line-of-sight velocities and nonthermal plasma motions. This spectral
  range also includes several pairs of density-sensitive lines.

---------------------------------------------------------
Title: Nonthermal Velocity Evolution in the Precursor Phase of a
    Solar Flare
Authors: Harra, L. K.; Matthews, S. A.; Culhane, J. L.
2001ApJ...549L.245H    Altcode:
  We present observations of two solar flares occurring in Active Region
  7590 on 1993 October 3 using data from the Yohkoh spacecraft. The
  hard X-ray bursts from the two flares occurred within an 18 minute
  interval, with the soft X-ray emission having a shorter separation of
  ~5 minutes. Both flares occurred within one Yohkoh orbit, and hence
  we have continuous coverage of the soft X-ray line broadening at the
  peak of the first flare, reducing to the active region level of 33.5
  km s<SUP>-1</SUP> in S XV (66.1 km s<SUP>-1</SUP> in Ca XIX) and then
  increasing to the peak in the second flare. The rise above the active
  region background level begins 11 minutes before the start of the second
  flare as defined by the start of the hard X-ray emission. During this
  extended rise time of V<SUB>nt</SUB>, there is no increase in the light
  curves or the electron temperature. We suggest that this increase is
  an indicator of turbulent changes in the active region prior to the
  flare that are related to the flare trigger mechanism.

---------------------------------------------------------
Title: Improving the effectiveness of international collaboration
    in space science
Authors: Culhane, J. L.; Worms, J. C.
2001SpPol..17..179C    Altcode:
  From the start of the 20th century, a strong tradition of collaboration
  has developed in the physical sciences. World War II and the following
  period changed this situation with a quickening of the pace of
  application. Thus, while basic research continues to benefit from
  collaboration among scientists worldwide, the increasingly complex
  background in which science evolves, through higher implementation
  costs and more difficult approval processes, renders collaboration
  among nations ever more pressing. Space science, with its comparatively
  high access cost but large fundamental importance, substantial public
  appeal and outstanding ability to motivate young people, shares this
  need. This article focuses on a recent ESSC-ESF study undertaken to
  improve the effectiveness of such cooperative efforts. Related findings
  and recommendations are presented along with a proposed operational
  structure for their implementation.

---------------------------------------------------------
Title: The Temperature of The Extended Solar Corona
Authors: Foley, C. R.; Culhane, J. L.; Mackay, D.
2001IAUS..203..505F    Altcode:
  We use the Coronal Diagnostic Spectrometer instrument on board the
  Solar and Heliospheric Observatory to analyse coronal helmet streamer
  structures observed close to the solar minimum / maximum on the 1996
  July 8 / 1999 July 4-5th. The radial variation of peak electron
  temperature is extracted out to 2 solar radii. These are found to
  agree well with Yohkoh observations close to the solar maximum, but
  are found to be reduced by around half a million close to the solar
  minimum. Extrapolations of the photospheric field observations of MDI
  are used to aid interpreted with regard to the energy depostion in
  the low corona and solar wind.

---------------------------------------------------------
Title: Soft X-ray/EUV Wavelengths
Authors: Cruddace, R. G.; Kowalski, M. P.; Yentis, D. J.; Fritz,
   G. G.; Gursky, H.; Barstow, M. A.; Bannister, N. P.; Fraser, G. W.;
   Culhane, J. L.; Lapington, J. S.; Barbee, T. W., Jr.; Kordas, J. F.;
   Heidemann, K.
2001AGM....18.P119C    Altcode: 2001AGAb...18R.194C
  Astrophysical spectrometers of high resolving power (R~ 10000) and high
  effective area (&gt;100 cm<SUP>2</SUP>), working in the 50-300 Å band,
  are feasible using normal-incidence, multilayer-coated, ion-etched
  diffraction optics. They show promise for studying the structure,
  density, temperature, composition and dynamic characteristics
  of, for example, stellar coronae, white dwarf atmospheres and the
  interstellar medium. We describe a prototype instrument, employing a
  microchannelplate detector in the focal-plane, which in February 2001
  was flown successfully on a NASA sounding rocket. This instrument had
  a resolving power of 3000, an effective area of 3 cm<SUP>2</SUP>, and
  operated in the band 220-245 Å band. In this mission the spectrometer
  obtained a high-resolution spectrum of the white dwarf G191-B2B,
  during an observation lasting 300 seconds, The primary scientific
  goal was to detect ionised helium in the spectrum, to distinguish
  between the interstellar and photospheric components, and with these
  results to elucidate the evolutionary path of this star. We describe
  the results of the data analysis performed to date.

---------------------------------------------------------
Title: Preface
Authors: Culhane, J. L.; Bentley, R. D.; Doyle, G.
2001AdSpR..26.1711C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Location of the source of soft X-ray non-thermal line
    broadenings in a solar flare
Authors: Ranns, N. D. R.; Matthews, S. A.; Harra, L. K.; Culhane, J. L.
2000A&A...364..859R    Altcode:
  We determine the location of the source of the non-thermal Soft
  X-ray line broadenings in an M1.7 two-ribbon solar flare using
  multi-wavelength observations. Using a combination of the Yohkoh Soft
  X-ray Telescope (SXT), Hard X-ray Telescope (HXT), Bragg Crystal
  Spectrometer (BCS) and the Transition Region and Coronal Explorer
  (TRACE), we find the source of the non-thermal broadenings, at their
  peak value, to be located in and above the SXR flare loops, not at the
  flare loop footpoints. After eliminating the footpoints as a potential
  source we discuss the likelihood that the source of non-thermally
  broadened emission lines is either evaporating chromospheric plasma
  or plasma above the Soft X-ray flare loop that is associated with the
  flare energy release.

---------------------------------------------------------
Title: Extreme-ultraviolet imaging spectrometer designed for the
    Japanese Solar-B satellite
Authors: Culhane, J. L.; Korendyke, Clarence M.; Watanabe, Tetsuya;
   Doschek, George A.
2000SPIE.4139..294C    Altcode:
  The Extreme-ultraviolet Imaging Spectrometer combines, for the first
  time, high spectral, spatial and temporal resolution in a satellite
  based, solar extreme ultraviolet instrument. The instrument optical
  design consists of a multilayer-coated off- axis paraboloid mirror
  telescope followed by a toroidal grating spectrometer. The instrument
  includes thin film aluminum filters to reject longer wavelength solar
  radiation and employs CCD detectors at the focal plane. The telescope
  mirror is articulated to allow sampling of a large fraction of the
  solar surface from a single spacecraft pointing position. Monochromatic
  images are obtained either by rastering the solar image across the
  narrow entrance slit or by using a wide slit or slot in place of
  the slit. Monochromatic images of the region centered on the slot are
  obtained in a single exposure. Half of each optic is coated to maximize
  reflectance at 195 angstrom; the other half is coated to maximize
  reflectance at 270 angstrom. The two EUV wavelength bands were selected
  to optimize spectroscopic plasma diagnostic capabilities. Particular
  care was taken to choose wavelength ranges with relatively bright
  emission lines to obtain precision line of sight and turbulent bulk
  plasma velocity measurements from observed line profiles. The EIS
  spectral range contains emission lines formed over a temperature
  range from approximately 10<SUP>5</SUP> - 10<SUP>7</SUP> K. The
  wavelength coverage also includes several density sensitive emission
  line pairs. These line pairs provide spatial resolution independent
  density diagnostics at nominal coronal temperatures and densities. Each
  wavelength band is imaged onto a separate CCD detector. The main EIS
  instrument characteristics are: wavelength bands -- 180 - 204 angstrom
  and 250 - 290 angstrom; spectral resolution -- 0.0223 angstrom/pixel
  (23 - 34 km/second-pixel); slit dimensions -- 4 slits: 1 X 1024 arc-
  seconds and 50 X 1024 arc-seconds with two positions unspecified as
  of this writing; fine raster range -- &gt;6 arc-minutes on the sun;
  coarse raster range -- &gt; 1600 arc- seconds on the sun; largest
  spatial field of view in a single exposure -- 50 X 1024 arc-seconds;
  nominal time resolution for active region velocity studies -- 3.4s. The
  Solar-B satellite is scheduled for launch in August 2005 into a nominal
  600 km sun-synchronous orbit.

---------------------------------------------------------
Title: The Energy Supply to X-ray Bright Points
Authors: McDonald, L.; Culhane, J. L.; Harra, L. K.; Matthews, S. A.
2000SoPh..196..137M    Altcode:
  X-ray bright points (XBPs) are usually assumed to be isolated
  structures in the solar atmosphere that are powered exclusively by
  magnetic reconnection. We analyse a large XBP that does not satisfy
  this assumption. The XBP is observed to be connected to an active region
  approximately 280 000 km away by a magnetic loop. We find that the soft
  X-ray intensity and thermal energy of the XBP are very sensitive to the
  existence of the magnetic loop. Both the intensity and energy decrease
  significantly at the times when the loop disappears, indicating that
  the loop is a medium for energy transfer from the active region to
  the XBP. We deduce that the mechanism for the energy transfer is most
  likely to be Alfvén or fast-mode magnetoacoustic waves created by
  photospheric motions in the active region. These waves can dissipate
  energy at the density gradient between the XBP and the loop via phase
  mixing or resonant absorption.

---------------------------------------------------------
Title: A Method to Determine the Heating Mechanisms of the Solar
    Corona
Authors: Priest, E. R.; Foley, C. R.; Heyvaerts, J.; Arber, T. D.;
   Mackay, D.; Culhane, J. L.; Acton, L. W.
2000ApJ...539.1002P    Altcode:
  One of the paradigms about coronal heating has been the belief that the
  mean or summit temperature of a coronal loop is completely insensitive
  to the nature of the heating mechanisms. However, we point out that
  the temperature profile along a coronal loop is highly sensitive to
  the form of the heating. For example, when a steady state heating
  is balanced by thermal conduction, a uniform heating function makes
  the heat flux a linear function of distance along the loop, while
  T<SUP>7/2</SUP> increases quadratically from the coronal footpoints;
  when the heating is concentrated near the coronal base, the heat flux
  is small and the T<SUP>7/2</SUP> profile is flat above the base;
  when the heat is focused near the summit of a loop, the heat flux
  is constant and T<SUP>7/2</SUP> is a linear function of distance
  below the summit. It is therefore important to determine how the
  heat deposition from particular heating mechanisms varies spatially
  within coronal structures such as loops or arcades and to compare it
  to high-quality measurements of the temperature profiles. We propose
  a new two-part approach to try and solve the coronal heating problem,
  namely, first of all to use observed temperature profiles to deduce the
  form of the heating, and second to use that heating form to deduce the
  likely heating mechanism. In particular, we apply this philosophy to
  a preliminary analysis of Yohkoh observations of the large-scale solar
  corona. This gives strong evidence against heating concentrated near the
  loop base for such loops and suggests that heating uniformly distributed
  along the loop is slightly more likely than heating concentrated at
  the summit. The implication is that large-scale loops are heated in
  situ throughout their length, rather than being a steady response
  to low-lying heating near their feet or at their summits. Unless
  waves can be shown to produce a heating close enough to uniform, the
  evidence is therefore at present for these large loops more in favor
  of turbulent reconnection at many small randomly distributed current
  sheets, which is likely to be able to do so. In addition, we suggest
  that the decline in coronal intensity by a factor of 100 from solar
  maximum to solar minimum is a natural consequence of the observed
  ratio of magnetic field strength in active regions and the quiet Sun;
  the altitude of the maximum temperature in coronal holes may represent
  the dissipation height of Alfvén waves by turbulent phase mixing;
  and the difference in maximum temperature in closed and open regimes
  may be understood in terms of the roles of the conductive flux there.

---------------------------------------------------------
Title: Emerging flux as a driver for homologous flares
Authors: Ranns, N. D. R.; Harra, L. K.; Matthews, S. A.; Culhane, J. L.
2000A&A...360.1163R    Altcode:
  We present multi-wavelength observations of 2 M-class solar flares
  observed by SoHO and Yohkoh, which appear to be homologous. By
  examination of the flare loop morphology and footpoints we propose
  a schematic reconnection scenario of a two loop interaction in
  a quadrupolar magnetic configuration, for both flares (Machado
  ?; Mandrini ?). After the first flare, the combination of chance
  emergence of new flux at an opportune location and a subsequent flare,
  of the type described by Heyvaerts et al. (?), form a new quadrupolar
  configuration in which the second flare occurred. Therefore though the
  two M-class flares are homologous by definition, they appear to conform
  to a scenario in which the preflare conditions are reformed after the
  first flare by emerging flux, rather than models which involve the
  continual shearing of a single magnetic structure.

---------------------------------------------------------
Title: Observations of Solar Flares
Authors: Culhane, J. L.
1999ESASP.448.1337C    Altcode: 1999mfsp.conf.1337C; 1999ESPM....9.1337C
  No abstract at ADS

---------------------------------------------------------
Title: Nonthermal Electron Energy Deposition in the Chromosphere
    and the Accompanying Soft x-ray Flare Emission
Authors: McDonald, L.; Harra-Murnion, L. K.; Culhane, J. L.
1999SoPh..185..323M    Altcode:
  We analyse four solar flares which have energetic hard X-ray emissions,
  but unusually low soft X-ray flux and GOES class (C1.0-C5.5). These are
  compared with two other flares that have soft and hard X-ray emission
  consistent with a generally observed correlation that shows increasing
  hard X-ray accompanied by increasing soft X-ray flux. We find that
  in the four small flares only a small percentage of the nonthermal
  electron beam energy is deposited in a location where the heating rate
  of the electron beam exceeds the radiative cooling rate of the ambient
  plasma. Most of the beam energy is subsequently radiated away into
  the cool chromosphere and so cannot power chromospheric evaporation
  thus reducing the soft X-ray emission. We also demonstrate that in the
  four small flares the nonthermal electron beam energy is insufficient
  to power the soft X-ray emitting plasma. We deduce that an additional
  energy source is required, and this could be provided by a DC-electric
  field (where quasi-static electric field channels in the coronal loops
  accelerate electrons, and those electrons with velocity below a critical
  velocity will heat the ambient plasma via Joule heating) in preference
  to a loop-top thermal source (where heat flux deposited in the corona
  is conducted along magnetic field lines to the chromosphere, heating the
  coronal plasma and giving rise to further chromospheric evaporation).

---------------------------------------------------------
Title: Flare dynamics.
Authors: Antonucci, E.; Alexander, D.; Culhane, J. L.; de Jager, C.;
   MacNeice, P.; Somov, B. V.; Zarro, D. M.
1999mfs..conf..331A    Altcode:
  The following topics were dealt with: results from soft X-ray spectra,
  chromospheric evaporation, nature of nonthermal line broadening,
  flare modelling.

---------------------------------------------------------
Title: Omc: AN Optical Monitoring Camera for Integral
Authors: Giménez, A.; Mas-Hesse, J. M.; Jamar, C.; McBreen, B.;
   Culhane, J. L.; Fabregat, J.; Swings, J. P.; Meurs, E.; Torra, J.;
   Hudec, R.
1999ApL&C..39..347G    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Nature of the heating mechanism for the diffuse solar corona
Authors: Priest, E. R.; Foley, C. R.; Heyvaerts, J.; Arber, T. D.;
   Culhane, J. L.; Acton, L. W.
1998Natur.393..545P    Altcode:
  The temperature of the Sun's outer atmosphere (the corona) exceeds that
  of the solar surface by about two orders of magnitude, but the nature
  of the coronal heating mechanisms has long been a mystery. The corona
  is a magnetically dominated environment, consisting of a variety of
  plasma structures including X-ray bright points, coronal holes and
  coronal loops. The latter are closed magnetic structures that occur
  over a range of scales and are anchored at each end in the solar
  surface. Large-scale regions of diffuse emission are made up of many
  long coronal loops. Here we present X-ray observations of the diffuse
  corona from which we deduce its likely heating mechanism. We find that
  the observed variation in temperature along a loop is highly sensitive
  to the spatial distribution of the heating. From a comparison of
  the observations and models we conclude that uniform heating gives
  the best fit to the loop temperature distribution, enabling us to
  eliminate previously suggested mechanisms of low-lying heating near
  the footpoints of a loop. Our findings favour turbulent breaking and
  reconnection of magnetic field lines as the heating mechanism of the
  diffuse solar corona.

---------------------------------------------------------
Title: OMC: An optical monitoring camera for INTEGRAL
Authors: Mas-Hesse, J. M.; Giménez, A.; Jamar, C.; McBreen, B.;
   Culhane, J. L.; Fabregat, J.; Swings, J. P.; Meurs, E.; Torra, J.;
   Hudec, R.; OMC Technical Team
1998PhST...77...44M    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: RESIK: High Sensitivity Soft X-ray Spectrometer for the Study
    of Solar Flare Plasma
Authors: Sylwester, J.; Gaicki, I.; Kordylewski, Z.; Nowak, M.;
   Kowalinski, S.; Sjarkowski, M.; Bentley, W.; Trzebinski, R. D.;
   Whyndham, M. W.; Guttridge, P. R.; Culhane, J. L.; Lang, J.; Phillips,
   K. J. H.; Brown, C. M.; Doschek, G. A.; Oraevsky, V. N.; Boldyrev,
   S. I.; Kopaev, I. M.; Stepanov, A. I.; Klepikov, V. Yu.
1998ESASP.417..313S    Altcode: 1998cesh.conf..313S
  No abstract at ADS

---------------------------------------------------------
Title: Iron and calcium abundances in solar flares from the
    multitemperature analysis of X-ray spectra (abstract)
Authors: Fludra, A.; Bentley, R. D.; Culhane, J. L.; Lemen, J. R.;
   Sylwester, J.
1998PAICz..88...91F    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Scientific Achievements of the YOHKOH Mission
Authors: Culhane, J. L.
1998ESASP.417...55C    Altcode: 1998cesh.conf...55C
  No abstract at ADS

---------------------------------------------------------
Title: The Solar Flare Dynamics Imager: A Low-Cost Mission for This
    Solar Maximum
Authors: Wulser, J. -P.; Bruner, M. E.; Strong, K. T.; Canfield,
   R. C.; Culhane, J. L.; Mariska, J. T.; Polidan, R.
1997SPD....28.0232W    Altcode: 1997BAAS...29R.898W
  The Solar Flare Dynamics Imager (SolFDI) is a very low-cost flare
  mission proposed for this upcoming solar maximum. It is based on a small
  solar EUV telescope/spectrograph for Spartan Lite, NASA's new ejectable
  hitchhiker spacecraft. The experiment's main scientific objective is
  to investigate the spatial, temporal, and velocity structure of the
  upflowing hot plasma frequently observed in soft X-ray lines during
  solar flares. Past observations were spatially unresolved, and the
  nature of these plasma flows, and their relationship with the impulsive
  phase flare energy release are not well understood. The second objective
  is to image the spatial and velocity structure of eruptive flares. Such
  observations can ultimately reveal the true three-dimensional geometry
  of the eruptive component of the flare. The Solar Flare Dynamics
  Imager will observe flares in a few selected extreme ultraviolet lines,
  including a high temperature Fe XXIV line. The instrument uses normal
  incidence multilayer coated optics to provide simultaneous imaging and
  spectroscopy in these lines with good spatial, spectral, and temporal
  resolution. The instrument is designed to fit within the envelope
  of the Spartan Lite ejectable hitchhiker spacecraft. Spartan Lite is
  smaller, and costs a fraction of a SMEX spacecraft. But if launched
  into the upcoming solar maximum, its 6-12 month mission duration would
  be sufficient to achieve SolFDI's scientific objectives.

---------------------------------------------------------
Title: Isolating the Footpoint Characteristics of a Solar Flare Loop
Authors: Harra-Murnion, L. K.; Culhane, J. L.; Hudson, H. S.; Fujiwara,
   T.; Kato, T.; Sterling*, A. C.
1997SoPh..171..103H    Altcode:
  We analyse the physical characteristics of a C5.7 class flare which
  was observed on 27 September, 1993 using data from the soft X-ray
  telescope (SXT), the Bragg crystal spectrometer (BCS), and the hard
  X-ray telescope (HXT) on Yohkoh. The flare takes the form of a simple
  loop which is much brighter at one of its footpoints than anywhere
  else for a period of 2 min. During this time there is an increase in
  the soft X-ray fluxes, and a corresponding peak in hard X-rays. The
  parameters derived from the hard X-ray and soft X-ray spectra and images
  are assumed to be from the footpoint. This flare showed two peaks in
  the non-thermal velocity, the first one simultaneous with the footpoint
  brightening. The non-thermal velocity corresponding to these first few
  minutes is unusually large - by a factor of 80%, 68%, and 26% relative
  to the second peak in the Fexxv, Caxix, and Sxv channels respectively.

---------------------------------------------------------
Title: OMC: An Optical Monitoring Camera for INTEGRAL
Authors: Giménez, A.; Mas-Hesse, J. M.; Jamar, C.; McBreen, B.;
   Culhane, J. L.; Fabregat, J.; Swings, J. P.; Meurs, E.; Torra, J.;
   Hudec, R.; OMC technical Team
1997ESASP.382..613G    Altcode: 1997trun.conf..613G
  No abstract at ADS

---------------------------------------------------------
Title: An investigation of small goes flares with intense hard
    x-ray bursts
Authors: McDonald, L.; Harra-Murnion, L. K.; Culhane, J. L.;
   Schwartz, A.
1997AdSpR..20.2327M    Altcode:
  Most solar flare observations show that intense hard X-ray bursts come
  from large flares that have a large GOES classification (large peak 1
  - 8 A˚ flux). This correlation, known as the “Big Flare Syndrome”,
  suggests that more intense flares tend to have harder spectra. We have
  observed 7 flares that are exceptions to this. These flares have small
  GOES classifications ranging from B1.4 to C5.5 and peak hard X-ray
  count rates similar to those often observed from M class flares. This
  paper examines the cause of this anomoly using the Yohkoh Soft X-Ray
  Telescope, Hard X-Ray Telescope, and Bragg Crystal Spectrometer. Two
  hypotheses are proposed for the exceptions: (1) flares with multiple
  magnetic loops and common footpoints, producing multiple hard X-ray
  emission regions and low density thermal plasma distributed over a
  large volume, and (2) high densities in the magnetic loops restricting
  the propagation of the non-thermal electrons in the loop after magnetic
  reconnection has occurred and suppressing chromospheric evaporation. Two
  of the flares support the first hypothesis. The other flares either
  have data missing or are too small to be properly analysed by the
  Yohkoh instruments.

---------------------------------------------------------
Title: High-Resolution Observations of the Extreme Ultraviolet Sun
Authors: Harrison, R. A.; Fludra, A.; Pike, C. D.; Payne, J.;
   Thompson, W. T.; Poland, A. I.; Breeveld, E. R.; Breeveld, A. A.;
   Culhane, J. L.; Kjeldseth-Moe, O.; Huber, M. C. E.; Aschenbach, B.
1997SoPh..170..123H    Altcode:
  This paper presents first results of the Coronal Diagnostic Spectrometer
  (CDS) recently launched aboard the Solar and Heliospheric Observatory
  (SOHO). CDS is a twin spectrometer, operating in the extreme ultraviolet
  range 151-785 Å. Thus, it can detect emission lines from trace
  elements in the corona and transition region which will be used to
  provide diagnostic information on the solar atmosphere. In this paper,
  we present early spectra and images, to illustrate the performance of
  the instrument and to pave the way for future studies.

---------------------------------------------------------
Title: YOHKOH observations of the solar corona
Authors: Culhane, J. L.
1997AdSpR..19.1839C    Altcode:
  The Yohkoh soft X-ray telescope obtains several images every 90
  minutes. Data from the declining phase of the solar cycle have been
  used to compare the X-ray signal with other indicators of activity
  and to study coronal heating. X-ray emission from a north polar
  coronal hole is found broadly consistent with results of previous
  EUV observations. In diffuse emission regions, temperature rises to
  around 2.2 MK and levels off in the height range 1.5 - 1.9 R_o. Such
  emission underlies streamers and may be the source of the low-speed
  solar wind. X-ray signatures for Coronal Mass Ejection (CME) events
  which involve the detection of reduced X-ray intensities in the corona,
  have been developed with Yohkoh data. CME observations are described.

---------------------------------------------------------
Title: Extreme ultraviolet observations of the solar corona: first
    results from the coronal diagnostic spectrometer on SOHO
Authors: Harrison, R. A.; Fludra, A.; Sawyer, E. C.; Culhane, J. L.;
   Norman, K.; Poland, A. I.; Thompson, W. T.; Kjeldseth-Moe, O.;
   Aschenbach, B.; Huber, M. C. E.; Gabriel, A. H.; Mason, H. E.
1997AdSpR..20.2239H    Altcode:
  We present first results from the Coronal Diagnostic Spectrometer (CDS)
  aboard the ESA/NASA Solar and Heliospheric Observatory (SOHO). CDS is
  a double spectrometer operating in the 151-785 A˚ range. This region
  of the solar spectrum is rich in emission lines from trace elements
  in the solar atmosphere, which can be used to derive diagnostic
  information on coronal and transition region plasma. Early spectra are
  presented and well identified lines are listed. In addition, examples
  of images in selected wavelength ranges are shown, for a prominence,
  a loop system and a bright point, demonstrating well the power of such
  extreme ultraviolet observations.

---------------------------------------------------------
Title: The ISO Long-Wavelength Spectrometer.
Authors: Clegg, P. E.; Ade, P. A. R.; Armand, C.; Baluteau, J. -P.;
   Barlow, M. J.; Buckley, M. A.; Berges, J. -C.; Burgdorf, M.; Caux,
   E.; Ceccarelli, C.; Cerulli, R.; Church, S. E.; Cotin, F.; Cox, P.;
   Cruvellier, P.; Culhane, J. L.; Davis, G. R.; di Giorgio, A.; Diplock,
   B. R.; Drummond, D. L.; Emery, R. J.; Ewart, J. D.; Fischer, J.;
   Furniss, I.; Glencross, W. M.; Greenhouse, M. A.; Griffin, M. J.; Gry,
   C.; Harwood, A. S.; Hazell, A. S.; Joubert, M.; King, K. J.; Lim, T.;
   Liseau, R.; Long, J. A.; Lorenzetti, D.; Molinari, S.; Murray, A. G.;
   Naylor, D. A.; Nisini, B.; Norman, K.; Omont, A.; Orfei, R.; Patrick,
   T. J.; Pequignot, D.; Pouliquen, D.; Price, M. C.; Nguyen-Q-Rieu;
   Rogers, A. J.; Robinson, F. D.; Saisse, M.; Saraceno, P.; Serra, G.;
   Sidher, S. D.; Smith, A. F.; Smith, H. A.; Spinoglio, L.; Swinyard,
   B. M.; Texier, D.; Towlson, W. A.; Trams, N. R.; Unger, S. J.; White,
   G. J.
1996A&A...315L..38C    Altcode:
  The Long-Wavelength Spectrometer (LWS) is one of two complementary
  spectrometers aboard the European Space Agency's Infrared Space
  Observatory (ISO) (Kessler et al., 1996A&amp;A...315L..49D). It operates
  over the wavelength range 43-196.9μm at either medium (about 150
  to 200) or high (6800 to 9700) spectral resolving power. This Letter
  describes the instrument and its modes of operation; a companion paper
  (Swinyard et al, 1996) describes its performance and calibration.

---------------------------------------------------------
Title: Department of Space and Climate Physics, (Mullard Space Science
    Laboratory), University College London. Report for the period 1993
    April 1 to 1995 March 31.
Authors: Culhane, J. L.
1996QJRAS..37..373C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: YOHKOH Observations of Fe XXVI X-Ray Line Emission from
    Solar Flares
Authors: Pike, C. D.; Phillips, K. J. H.; Lang, J.; Sterling, A.;
   Watanabe, T.; Hiei, E.; Culhane, J. L.; Cornille, M.; Dubau, J.
1996ApJ...464..487P    Altcode:
  We report on observations from the Bragg Crystal Spectrometer (B CS)
  on board the Japanese solar flare spacecraft Yohkoh showing Fe XXVI
  Lyα X-ray line emission at 1.78 Å. Some 75 events over a 2 yr period
  between 1991 December 6 and 1993 December 31 have been analyzed. The
  greater sensitivity of the BCS compared with previous instruments has
  enabled such emission to be detected from a wider group of flares than
  has previously been possible. The likelihood of detecting Fe XXVI lines
  in a flare is found to increase sharply with the electron temperature
  obtained from the Fe XXV line spectrum, also observed by the BCS,
  and with GOES X-ray class. The width of the Lyα<SUB>1</SUB>, line,
  measured after the impulsive stage, is greater than that determined by
  thermal Doppler broadening, but this is explained by the nonzero spatial
  extent of flares. Electron temperatures from the intensity ratio of a
  nearby feature due to Fe XXV dielectronic satellites and the Fe XXVI
  Lyα<SUB>1</SUB> line are obtained from new atomic parameters from
  the superstructure code, details of which are described. This revises
  earlier calculations that have been extensively used. Comparison
  of these temperatures with those from the Fe XXV spectra provides
  evidence for a single loose grouping of flares, with the difference
  between the two temperatures ranging from nearly zero to about 20 MK. A
  "superhot" component would seem to be more or less developed according
  to whether the temperature difference is large or nearly zero. Flares
  at both extremes are examined in detail. The gradually varying part
  of the 14-33 keV X-ray emission for these events, as observed by the
  Hard X-ray Telescope on Yohkoh, has a hardness ratio corresponding
  to temperatures and emission measures similar to those from Fe XXVI
  line ratios, pointing to a common origin for their emission. Many of
  the flares studied occurred in particular active regions with great
  magnetic complexity, although Fe XXVI flares do not seem to be a
  distinct class within large X-ray flares.

---------------------------------------------------------
Title: Fe XXVI line emission observed by YOHKOH
Authors: Pike, C. D.; Pillips, K. J. H.; Lang, J.; Sterling, A.;
   Watanabe, T.; Hiei, E.; Culhane, J. L.
1996AdSpR..17d..51P    Altcode: 1996AdSpR..17...51P
  Observations from the Bragg Crystal Spectrometer (BCS) on board
  the Japanese solar flare space-craftYohkoh showing Fe xxvi Ly-alpha
  X-ray line emission at about 1.78 Angstroms are reported. Some 75
  events over a two-year-long period between December 1991 and December
  1993 have been analyzed. The greater sensitivity of the BCS compared
  with previous instruments has enabled such emission to be detected
  from a wider group of flares than has previously been possible. The
  likelihood of detecting Fe xxvi lines in a flare is found to increase
  sharply with the electron temperature obtained from the Fe xxv line
  spectrum, also observed by the BCS, and with GOES X-ray class. The
  width of the Lyalpha_1 line, measured after the impulsive stage, is
  rather greater than that determined by thermal Doppler broadening,
  and if the excess broadening is attributed to turbulence, velocities
  of up to 70 km s^-1 are indicated. Comparison of electron temperatures
  obtained from the Fe xxvi spectrum with Fe xxv temperatures provides
  evidence for a single loose grouping of flares, with the difference
  between the two temperatures ranging from nearly zero to about 20 x
  10^6K. A “superhot” component would seem to be more or less developed
  according as the temperature difference is large or nearly zero.

---------------------------------------------------------
Title: YOHKOH observations of high temperature plasma in solar flares
Authors: Culhane, J. L.
1996AdSpR..17d..29C    Altcode: 1996AdSpR..17...29C
  After a summary of results from previous missions and of Hα
  observations, results from Yohkoh are presented. These deal with
  plasma motions, impulsive soft X-ray footpoint brightenings and the
  distribution of X-ray emitting plasma in flaring coronal loops. The
  observations suggest that soft X-ray emission originates from locally
  heated gas and from plasma that flows up from the chromosphere following
  energy transport from the flare site by both thermal conduction and
  non-thermal electrons. A DC electric field model is reviewed which
  can explain the observations.

---------------------------------------------------------
Title: Solar flare, coronal and heliospheric
    dynamics. Proceedings. E2.2 Symposium of COSPAR Scientific Commission
    E which was held during the Thirtieth COSPAR Scientific Assembly,
    Hamburg (Germany), 11 - 21 Jul 1994.
Authors: Culhane, J. L.; Hiei, E.
1996AdSpR..17d....C    Altcode: 1996AdSpR..17.....C
  The following topics were dealt with: solar flare studies, Yohkoh
  observations of magnetic reconnection, high temperature plasma in solar
  flares, hard X-ray fluxes in solar flares, particle acceleration during
  flares, ground-based observations of flares, UV observations, radio
  bursts, chromospheric condensations, energetic particle transport in
  solar flares, solar active regions, coronal structure, solar magnetic
  cycle, coronal holes, coronal dynamic phenomena, coronal magnetic
  fields, heliosphere dynamics, Ulysses data, interplanetary magnetic
  field, heliospheric density structure, signatures of fast coronal mass
  ejections in the interplanetary space, interplanetary shock waves,
  future missions and instrumentation.

---------------------------------------------------------
Title: Meeting Overview
Authors: Culhane, J. L.
1996ASPC..111....3C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Solar spectroscopy with the BCS on YOHKOH
Authors: Culhane, J. L.
1996ASPC..109..181C    Altcode: 1996csss....9..181C
  No abstract at ADS

---------------------------------------------------------
Title: Isolating the Footpoint Characteristics of a Solar Flare Loop
Authors: Harra-Murnion, L. K.; Culhane, J. L.; Fujiwara, T.; Hudson,
   H. S.; Kato, T.; Sterling, A. C.
1996mpsa.conf..527H    Altcode: 1996IAUCo.153..527H
  No abstract at ADS

---------------------------------------------------------
Title: Temperature Structure of the Diffuse Corona
Authors: Foley, C. R.; Culhane, J. L.; Acton, L. W.; Lemen, J. R.
1996mpsa.conf..419F    Altcode: 1996IAUCo.153..419F
  No abstract at ADS

---------------------------------------------------------
Title: Evolution of two small solar flares.
Authors: Fludra, A.; Doyle, J. G.; Metcalf, T.; Lemen, J. R.; Phillips,
   K. J. H.; Culhane, J. L.; Kosugi, T.
1995A&A...303..914F    Altcode:
  Data from the YOHKOH satellite have been analysed for two small flares
  (GOES class C) of total duration of 10 and 60 minutes. Upflows in S
  XV, Ca XIX and Fe XXV lines were compared and the presence of a range
  of upflow velocities was found. Emission from flare loop footpoints
  corresponding to plasma moving with a typical velocity of 200-400km/s
  is seen in soft X-ray images. In one of these events (23 June 1992),
  which occurred in sheared loops being part of a sparse magnetic arcade,
  with initial energy release taking place near one of the footpoints, a
  large proportion of upflowing plasma was seen at least 1 minute before
  the first peak in hard X-rays. In the second event (13 July 1992), the
  increase of soft X-ray emission began more than 3 minutes before, and
  weak mass upflows one minute before the rapid increase of temperature
  and the onset of the detectable hard X-ray emission. This event was
  probably triggered by emerging magnetic flux and accompanied by heating
  and restructuring of two nearby magnetic loops. In both events the
  emission measure of upflowing plasma is present simultaneously to,
  and is very well correlated in time with the hard X-ray flux in the
  14-23keV band. Differential emission measure in the temperature range
  5-60x10^6^K was derived from S XV, Ca XIX and Fe XXV line and continuum
  fluxes, and from images in two broad band soft X-ray filters, and
  used to analyse the thermal contribution to the hard X-ray emission. A
  non-thermal component of the hard X-ray emission is found at the peak
  of the 23 June 1992 flare. The hard X-ray emission in the 13 July 1992
  flare is primarily thermal, however, a possibility of an enhanced tail
  of the electron energy distribution above 14keV is also indicated. The
  chromospheric evaporation in these flares was driven both by electron
  beams and thermal conduction, with conduction predominating during most
  of the rise phase of the 13 July 1992 flare. In both events, the soft
  X-ray emission measure at flare maximum was a few times 10^48^cm^-3^
  with an electron temperature 19 and 24x10^6^K; the estimated lower
  limit of the electron density is ~10^11^cm^-3^. The broadening of
  Ca XIX spectral lines in the decay phase of these flares indicates
  persisting random motions with a velocity of 60km/s, which is very
  similar to the non-thermal broadening observed previously by SMM in
  M and X class flares.

---------------------------------------------------------
Title: Spacelab 2 measurement of the solar coronal helium abundance
Authors: Gabriel, A. H.; Culhane, J. L.; Patchett, B. E.; Breeveld,
   E. R.; Lang, J.; Parkinson, J. H.; Payne, J.; Norman, K.
1995AdSpR..15g..63G    Altcode: 1995AdSpR..15...63G
  The abundance of helium relative to hydrogen has been measured with
  the “Coronal Helium Abundance Spacelab Experiment” (CHASE) from the
  space shuttle Challenger in 1985. Previous solar measurements have
  proved difficult due to the temperature-sensitivity of the electron
  excitation rates for the observed lines. In this approach scattered
  Lyman Alpha (Lyalpha) radiation of helium and hydrogen formed in
  the corona were measured with a grazing-incidence spectrometer and
  compared with the intensity of the illuminating flux from the solar
  chromosphere. The abundance ratio by number of atoms was found to be
  0.070 with an uncertainty of 0.011. Scattered light in the telescope
  is the main source of error.

---------------------------------------------------------
Title: YOHKOH Results in the Context of the High-Latitude Heliosphere
Authors: Culhane, J. L.
1995SSRv...72...17C    Altcode:
  Designed primarily to study solar activity, Yohkoh includes an X-ray
  telescope that obtains full-sun coronal images which show a range of
  features. Coronal X-ray emission-exclusive of flares, is notable for
  its variability even in the largest structures. A mass ejection event
  is related to magnetic field reconnection. Such events exhibit both
  accelerated and decelerated behaviour. Coronal hole temperatures are
  estimated from the filter ratio method. A plasma component at around
  2.10<SUP>6</SUP> K is identified. X-ray emission is detected from
  the South polar coronal hole. A preliminary comparison of Spartan
  coronagraph images with Yohkoh data suggests that polar plumes or rays
  are not connected to bright points.

---------------------------------------------------------
Title: Observations of Coronal Temperature Structure by Yohkoh
Authors: Acton, L. W.; Culhane, J. L.; Lemen, J. R.; Sturrock, P. A.
1995SPD....26..615A    Altcode: 1995BAAS...27..964A
  No abstract at ADS

---------------------------------------------------------
Title: Temperature Structure of the Diffuse Corona
Authors: Foley, C. A.; Acton, L. W.; Culhane, J. L.; Lemen, J. R.
1995SPD....26..716F    Altcode: 1995BAAS...27R.969F
  No abstract at ADS

---------------------------------------------------------
Title: YOHKOH Results in the Context of the High-Latitude Heliosphere
Authors: Culhane, J. L.
1995hlh..conf...17C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Yohkoh observations of the creation of high-temperature plasma
    in the flare of 16 December 1991
Authors: Culhane, J. L.; Phillips, A. T.; Inda-Koide, M.; Kosugi,
   T.; Fludra, A.; Kurokawa, H.; Makishima, K.; Pike, C. D.; Sakao, T.;
   Sakurai, T.; Doschek, G. A.; Bentley, R. D.
1994SoPh..153..307C    Altcode:
  Yohkoh observations of an impulsive solar flare which occurred on 16
  December, 1991 are presented. This flare was a GOES M2.7 class event
  with a simple morphology indicative of a single flaring loop. X-ray
  images were taken with the Hard X-ray Telescope (HXT) and soft X-ray
  spectra were obtained with the Bragg Crystal Spectrometer (BCS)
  on board the satellite. The spectrometer observations were made at
  high sensivity from the earliest stages of the flare, are continued
  throughout the rise and decay phases, and indicate extremely strong
  blueshifts, which account for the majority of emission in CaXIX during
  the initial phase of the flare. The data are compared with observations
  from other space and ground-based instruments. A balance calculation
  is performed which indicates that the energy contained in non-thermal
  electrons is sufficient to explain the high temperature plasma which
  fills the loop. The cooling of this plasma by thermal conduction
  is independently verified in a manner which indicates that the loop
  filling factor is close to 100%. The production of `superhot' plasma
  in impulsive events is shown to differ in detail from the morphology
  and mechanisms appropriate for more gradual events.

---------------------------------------------------------
Title: The 1991 November 9 Flare at 03.2 UT: Observations from YOHKOH
Authors: Doschek, G. A.; Mariska, J. T.; Strong, K. T.; Bentley, R. D.;
   Brown, C. M.; Culhane, J. L.; Lang, J.; Sterling, A. C.; Watanabe, T.
1994ApJ...431..888D    Altcode:
  We discuss X-ray spectra and soft X-ray images of an M1.9 flare that
  occurred on 1991 November 9 near 03.2 UT. These data were obtained with
  instrumentation on the Japanese Yohkoh spacecraft. They cover the entire
  rise phase and peak flare emission, and the beginning of the decay
  phase. We determine the dynamics, temperature, and emission measure
  of the flare as inferred from the X-ray line profiles of resonance
  lines of Fe XXV, Ca XIX, and S XV. We discuss the morphology of the
  flare as inferred from the soft X-ray images. The November 9 flare is
  atypical in that a stronger than usual blueshifted emission component
  (relative to the stationary component) is observed for the resonance
  lines at flare onset. We discuss several methods for deconvolving the
  blueshifted component from the stationary component. The X-ray line
  profiles are consistent with predictions of numerical simulations
  of chromospheric evaporation. The X-ray images reveal a flare with a
  complicated loop geometry that is not fully understood. Many of the
  features in the images are moving upwards at speeds ranging from a
  few km/s to about 800 km/s. The blueshifted emission begins near the
  onset of hard X-ray emission, implying that particle acceleration and
  upflowing plasma have a common energy source.

---------------------------------------------------------
Title: Energy Transport Mechanisms and the Event of 16th December 1991
Authors: Culhane, J. L.; Phillips, A. T.; Kosugi, T.; Inda-Koide,
   M.; Pike, C. D.
1994kofu.symp..117C    Altcode:
  The flare of 16th December 1991 had relatively simple structure,
  which has made it useful for studing the energetics of chromospheric
  evaporation. Energy balance calculations for this flare support
  an electron beam energy deposition hypothesis for this event. The
  creation of `super-hot' plasma is also investigated, using YOHKOH Hard
  X-ray Telescope images. Contrary to previously reported events, the
  `super-hot' plasma in the 16th December flare is generated, and remains
  close to the chromospheric footpoints, with a decay time consistent
  with saturated thermal conduction to the chromosphere.

---------------------------------------------------------
Title: Long Duration Events in Magnetic Arcades and Large Loops
Authors: Fludra, A.; Jakimiec, J.; Tomczak, M.; Culhane, J. L.; Acton,
   L. W.
1994kofu.symp..393F    Altcode:
  A number of long duration flares, with decay time between 1 and
  17 hours, have been analysed using the Yohkoh Soft X-ray Telescope
  images and spectra from the Bragg Crystal Spectrometer. X-ray images
  suggest that these events typically occur in the following magnetic
  field configurations: magnetic arcade, expanding arch, or large loops
  triggered and heated up by a low-lying, compact, impulsive flare
  located below these high loops. A continued energy release is observed
  during decay of these events. Single loop flare models should not be
  indiscriminately applied to analysis of thermodynamics of these flares
  due to their more complex structure and restructuring of the magnetic
  field, and often increasing height.

---------------------------------------------------------
Title: Mullard Space Science Laboratory, University College
    London. Report for the period 1991 April 1 to 1993 March 31.
Authors: Culhane, J. L.
1994QJRAS..35..107C    Altcode: 1994QJRAS..35..107.
  No abstract at ADS

---------------------------------------------------------
Title: The Correlation of Solar Flare Hard X-Ray Bursts with Doppler
    Blueshifted Soft X-Ray Flare Emission
Authors: Bentley, R. D.; Doschek, G. A.; Simnett, G. M.; Rilee, M. L.;
   Mariska, J. T.; Culhane, J. L.; Kosugi, T.; Watanabe, T.
1994ApJ...421L..55B    Altcode:
  We have investigated the temporal correlation between hard X-ray
  bursts and the intensity of Doppler blueshifted soft X-ray spectral
  line emission. We find a strong correlation for many events that have
  intense blueshifted spectral signatures and some correlation in events
  with modest blueshifts. The onset of hard X-rays frequently coincides to
  within a few seconds with the onset of blueshifted emission. The peak
  intensity of blueshifted emission is frequently close in time to the
  peak of the hard X-ray emission. Decay rates of the blueshifted and hard
  X-ray emission are similar, with the decay of the blueshifted emission
  tending to lag behind the hard X-ray emission in some cases. There
  are, however, exceptions to these conclusions, and, therefore, the
  results should not be generalized to all flares. Most of the data for
  this work were obtained from instruments flown on the Japanese Yohkoh
  solar spacecraft.

---------------------------------------------------------
Title: Dynamics of a Low Energetic Solar Flare
Authors: Doyle, J. G.; Fludra, A.; Bentley, R. D.; Culhane, J. L.;
   Metcalf, T.; Lemen, J. R.; Kosugi, T.
1994ASPC...64..402D    Altcode: 1994csss....8..402D
  No abstract at ADS

---------------------------------------------------------
Title: The Flare of 16 December 1991
Authors: Culhane, J. L.; Phillips, A.; Pike, D.; Inda, M.; Kosugi,
   T.; Sakao, T.
1994xspy.conf...95C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Hα and X-Ray Signatures of Chromospheric Evaporation Observed
    during the Early Phase of the 15 November 1991 Flare
Authors: Wülser, J. -P.; Canfield, R. C.; Acton, L. W.; Culhane,
   J. L.; Phillips, A.; Fludra, A.; Sakao, T.; Masuda, S.; Kosugi, T.
1994xspy.conf...75W    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The 1992 January 5 Flare at 13.3 UT: Observations from YOHKOH
Authors: Doschek, G. A.; Strong, K. T.; Bentley, R. D.; Brown, C. M.;
   Culhane, J. L.; Fludra, A.; Hiei, E.; Lang, J.; Mariska, J. T.;
   Phillips, K. J. H.; Pike, C. D.; Sterling, A. C.; Watanabe, T.; Acton,
   L. W.; Bruner, M. E.; Hirayama, T.; Tsuneta, S.; Rolli, E.; Kosugi,
   T.; Yoshimori, M.; Hudson, H. S.; Metcalf, T. R.; Wuelser, J. -P.;
   Uchida, Y.; Ogawara, Y.
1993ApJ...416..845D    Altcode:
  We discuss X-ray spectra and soft X-ray images of an M1.9 flare that
  occurred on 1992 January 5 near 13.3 UT. These data were obtained
  with instrumentation on the Japanese Yohkoh spacecraft. They cover
  the entire rise phase of the flare. To supplement these data we have
  ground-based magnetograms and Hα spectroheliograms. We calculate
  the electron temperature and emission measure of the flare as a
  function of time during the early rise phase using X-ray spectral
  line intensities and line ratios. Using spectral line widths, line
  profile asymmetries, and wavelength shifts due to the Doppler effect,
  we calculate the dynamical properties of the flare. The time development
  of the morphology of the flare, as revealed by the soft X-ray images
  and the Hα spectroheliograms, and the physical quantities inferred
  from the X-ray spectra, are compared with chromospheric evaporation
  models. There is an enhancement of blueshifted emission that is closely
  correlated with the hard X-ray bursts. Heating of one loop in the flare
  is consistent with a conduction-evaporation model, but heating is found
  in several structures that do not appear to be physically associated
  with each other. No standard evaporation model can adequately explain
  all of the observations.

---------------------------------------------------------
Title: Yohkoh observations of plasma upflows during solar flares
Authors: Culhane, J. L.; Phillips, A. T.; Pike, C. D.; Fludra, A.;
   Bentley, R. D.; Bromage, B.; Doschek, G. A.; Hiei, E.; Inda, M.;
   Mariska, J. T.; Phillips, K. J. H.; Sterling, A. C.; Watanabe, T.
1993AdSpR..13i.303C    Altcode: 1993AdSpR..13..303C
  Observations of two flares, an M 2.2 event on 16 December, 1991 and the
  precursor to an X1 flare on 15 November, 1991 are presented. Spectra
  obtained with the Bragg Crystal Spectrometer (BCS) are compared with
  data from the Hard and Soft X-ray Telescopes (HXT, SXT) and the Wide
  Band Spectrometer (WBS) on the satellite. For both events the creation
  of upflowing plasma is detected. While the first event seems to conform
  well to the chromospheric evaporation model for high temperature plasma
  production, the behaviour for the second event is more complex.

---------------------------------------------------------
Title: Determination of coronal abundances of sulphur, calcium and
    iron using the yohkoh bragg crystal spectrometer
Authors: Fludra, A.; Culhane, J. L.; Bentley, R. D.; Doschek, G. A.;
   Hiei, E.; Phillips, K. J. H.; Sterling, A.; Watanabe, T.
1993AdSpR..13i.395F    Altcode: 1993AdSpR..13..395F
  Using spectra from the Bragg Crystal Spectrometer on Yohkoh we have
  derived coronal abundances of sulphur, calcium and iron during several
  flares from the ratio of the flux in the resonance line to the nearby
  continuum. Multi-thermal effects have been taken into account using
  differential emission measure analysis. We have also determined the
  abundance of S in cool active regions during a period of very low solar
  activity. We compare the coronal abundances of S, Ca and Fe with their
  photospheric values.

---------------------------------------------------------
Title: A Comparison of Solar Flare Hard X-Ray Bursts with Doppler
    Blue-Shifted Soft X-Ray Emission
Authors: Rilee, M. L.; Bentley, R. D.; Culhane, J. L.; Doschek, G. A.;
   Mariska, J. T.; Simnett, G. M.; Watanabe, T.
1993BAAS...25.1189R    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Requirements for future solar-physics missions with X-ray
    instrumentation.
Authors: Culhane, J. L.
1993ESASP1157..147C    Altcode: 1993srfs.book..147C
  Several overall requirements for solar X-ray missions are stated and
  a brief outline of the underlying coronal physics is presented. The
  available techniques for X-ray imaging of the Sun are discussed and
  compared with reference to previous and on-going missions. Solar
  X-ray spectroscopy is assessed in the same manner. Possible choices
  for future instruments in these two areas are discussed.

---------------------------------------------------------
Title: Yohkoh basks in sunlight
Authors: Culhane, Len
1993Natur.362..496C    Altcode:
  The Japanese Yohkoh solar-astronomy satellite uses a battery of
  X-ray instruments, including soft X-ray and hard X-ray telescopes,
  to study such complex magnetic field patterns as the reconnection
  of field lines, which is important for the release of energy in the
  solar atmosphere. By these means, X-ray jets have been observed in
  the corona; the magnetic bipolar nature of the coronal bright points
  has been firmly established as well.

---------------------------------------------------------
Title: The ROSAT Wide Field Camera all-sky survey of
    extreme-ultraviolet sources. I. The bright source catalogue.
Authors: Pounds, K. A.; Allan, D. J.; Barber, C.; Barstow, M. A.;
   Bertram, D.; Branduardi-Raymont, G.; Brebner, G. E. C.; Buckley, D.;
   Bromage, G. E.; Cole, R. E.; Courtier, M.; Cruise, A. M.; Culhane,
   J. L.; Denby, M.; Donoghue, D. O.; Dunford, E.; Georgantopoulos, I.;
   Goodall, C. V.; Gondhalekar, P. M.; Gourlay, J. A.; Harris, A. W.;
   Hassall, B. J. M.; Hellier, C.; Hodgkin, S.; Jeffries, R. D.; Kellett,
   B. J.; Kent, B. J.; Lieu, R.; Lloyd, C.; McGale, P.; Mason, K. O.;
   Matthews, L.; Mittaz, J. P. D.; Page, C. G.; Pankiewicz, G. S.; Pike,
   C. D.; Ponman, T. J.; Puchnarewicz, E. M.; Pye, J. P.; Quenby, J. J.;
   Ricketts, M. J.; Rosen, S. R.; Sansom, A. E.; Sembay, S.; Sidher, S.;
   Sims, M. R.; Stewart, B. C.; Sumner, T. J.; Vallance, R. J.; Watson,
   M. G.; Warwick, R. S.; Wells, A. A.; Willingale, R.; Willmore, A. P.;
   Willoughby, G. A.; Wonnacott, D.
1993MNRAS.260...77P    Altcode:
  The first all-sky survey for cosmic sources of extreme-ultraviolet
  radiation has been carried out with the UK Wide Field Camera on
  ROSAT. A first reduction of the survey data has yielded a catalogue
  of 383 relatively bright EW sources, forming the WFC Bright Source
  Catalogue. This represents a 30-fold increase in the number of
  astrophysical objects detected in the ~60-200 eV energy band and
  covers a flux range, in each of the two survey bands, of more than
  2000. A search of the (typically ~1 -arcmin) error circles of the WFC
  sources, using a variety of catalogues and the SIMBAD data base, has
  identified probable optical counterparts of 73 per cent, including many
  active stars, white dwarf stars and a variety of other galactic and
  extragalactic objects. A follow-up programme of optical spectroscopy
  has since added further identifications, but some 13 percent of the
  EUV sources remain unidentified. Details of the EUV source positions
  and count rates are given, together with optical identifications where
  known. Considerations of survey completeness allow source counts (log
  N-log S) to be derived for each survey band. It is found that the log
  N-log S distributions are unusually flat for the white dwarf stars,
  but almost Euclidean for the nearby main-sequence late-type stars. This
  is probably an effect of local (&lt;~ 100 pc) interstellar absorption,
  since the more (EUV) luminous white dwarfs are potentially detected at
  correspondingly greater distances than the late-type stars. In addition,
  the sky distribution of identified white dwarfs is highly non uniform
  also suggesting gross variations in the opacity of the interstellar
  medium within ~100 pc.

---------------------------------------------------------
Title: Determination of element abundances using the Yohkoh Bragg
    Crystal Spectrometer.
Authors: Fludra, A.; Culhane, J. L.; Bentley, R. D.; Doschek, G. A.;
   Hiei, E.; Phillips, K. J. H.; Sterling, A.; Watanabe, T.
1993uxrs.conf..542F    Altcode: 1993uxsa.conf..542F
  No abstract at ADS

---------------------------------------------------------
Title: Yohkoh BCS Observations of Doppler Shifts Early in Solar Flares
Authors: Mariska, J. T.; Doschek, G. A.; Sterling, A. C.; Culhane,
   J. L.; Hiei, E.; Watanabe, T.; Lang, J.
1992AAS...180.2308M    Altcode: 1992BAAS...24..761M
  No abstract at ADS

---------------------------------------------------------
Title: Time Variation of Solar Flare Temperatures Determined from
    YOHKOH BCS Spectra
Authors: Sterling, A. C.; Doschek, G. A.; Mariska, J. T.; Pike, C. D.;
   Culhane, J. L.; Hiei, E.; Watanabe, T.; YOHKOH BCS Team
1992AAS...180.3001S    Altcode: 1992BAAS...24..775S
  Bragg Crystal Spectrometer (BCS) X-ray spectra analysis from past
  satellite missions indicate that it is possible to estimate temperatures
  in highly ionized flare plasmas to within about 12\ resonance lines
  in different He-like ions. This procedure is particularly valuable
  in cases where other temperature measuring methods are insufficient,
  such as during the rise phase of flares with strong X-ray spectra
  blue shifts. Here we examine this ratio variation in several flares
  using data from the Fe XXV, Ca XIX, and S XV channels of the BCS
  experiment onboard the Yohkoh satellite. We select flares for
  which we have good rise phase data, and calibrate the ratios using
  dielectronic-to-resonance line ratios in selected Fe XXV spectra
  assuming constant elemental abundances in each event. The Yohkoh BCS is
  about an order of magnitude more sensitive than previous X-ray flare
  spectrometers, and is therefore able to examine the early stages of
  flare development in greater detail than previously possible. For this
  study we select events for which we have good rise phase data, but data
  well into the decay phase is available for a number of the selected
  events. This allows us, for the first time, to follow the evolution
  of flare spectra from relatively cool temperatures (~ 12 MK in Fe XXV)
  to previously quoted “typical" flare temperatures (~ 17 MK in Fe XXV).

---------------------------------------------------------
Title: Mullard Space Science Laboratory, University College
    London. Report for the period 1989 August 1 to 1991 March 31.
Authors: Culhane, J. L.
1991QJRAS..32..459C    Altcode: 1991QJRAS..32..459.
  No abstract at ADS

---------------------------------------------------------
Title: Position sensitive detectors in X-ray astronomy
Authors: Culhane, J. L.
1991NIMPA.310....1C    Altcode:
  Detectors for X-ray astronomy include gas filled proportional
  and scintillation counters, microchannel plates, CCDs and single
  photon microcalorimeters. The spatial and nondispersive spectral
  resolutions of all of these systems are compared in the light of
  present requirements. The current state of development in each of the
  four areas is then discussed and the salient features of each system
  evaluated. While the subject has seen gas filled detectors employed
  from the beginning, the need for improved spectral resolution combined
  with high quantum efficiency is leading to an increased emphasis on
  solid state detectors in spite of the difficulties involved in cooling
  these systems in orbit. Microchannel plates remain important photon
  energies less than 1 keV because of their excellent spatial resolution.

---------------------------------------------------------
Title: The Bragg Crystal Spectrometer for SOLAR-A
Authors: Culhane, J. L.; Hiei, E.; Doschek, G. A.; Cruise, A. M.;
   Ogawara, Y.; Uchida, Y.; Bentley, R. D.; Brown, C. M.; Lang, J.;
   Watanabe, T.; Bowles, J. A.; Deslattes, R. D.; Feldman, U.; Fludra,
   A.; Guttridge, P.; Henins, A.; Lapington, J.; Magraw, J.; Mariska,
   J. T.; Payne, J.; Phillips, K. J. H.; Sheather, P.; Slater, K.;
   Tanaka, K.; Towndrow, E.; Trow, M. W.; Yamaguchi, A.
1991SoPh..136...89C    Altcode:
  The Bragg Crystal Spectrometer (BCS) is one of the instruments which
  makes up the scientific payload of the SOLAR-A mission. The spectrometer
  employs four bent germanium crystals, views the whole Sun and observes
  the resonance line complexes of H-like FeXXVI and He-like FeXXV,
  CaXIX, and SXV in four narrow wavelength ranges with a resolving power
  (λ/Δλ) of between 3000 and 6000. The spectrometer has approaching
  ten times better sensitivity than that of previous instruments thus
  permitting a time resolution of better than 1 s to be achieved. The
  principal aim is the measurement of the properties of the 10 to 50
  million K plasma created in solar flares with special emphasis on the
  heating and dynamics of the plasma during the impulsive phase. This
  paper summarizes the scientific objectives of the BCS and describes
  the design, characteristics, and performance of the spectrometers.

---------------------------------------------------------
Title: A study of the flaring and quiscent X-ray and UV emission
    from II Pegasi.
Authors: Tagliaferri, G.; White, N. E.; Doyle, J. G.; Culhane, J. L.;
   Hassall, B. J. M.; Swank, J. H.
1991A&A...251..161T    Altcode:
  An investigation has been conducted of the rotational modulation of the
  transition-region UV and coronal X-ray emission for the RS CVn system II
  Pegasi. The X-ray light curve is dominated by a strong flare detected at
  orbital phase, where the minimum of the photometric wave occurred. The
  flare parameters derived show that the flare originates with a height
  greater than half the stellar radius. The characteristics of the flare
  are similar to those of a solar two-ribbon flare; a comparison of the
  midtransition region density with that in the coronal region shows a
  very steep pressure gradient.

---------------------------------------------------------
Title: Iron and calcium abundances in solar flares from the
    multi-temperature analysis of X-ray spectra
Authors: Fludra, A.; Bentley, R. D.; Culhane, J. L.; Lemen, J. R.;
   Sylwester, J.
1991AdSpR..11a.155F    Altcode: 1991AdSpR..11Q.155F
  A generalized method of calculating the distribution of the emission
  measure with temperature (DEM) for optically thin plasma has been
  developed. The method simultaneously uses line flux ratios in addition
  to line fluxes. When a ratio of lines from the same element is used,
  the resulting DEM is independent of this element's abundance. The method
  has been applied to derive the absolute abundances of iron in solar
  flares from X-ray spectra recorded by the Bent Crystal Spectrometer on
  SMM. The iron abundances have been found to vary between flares. The
  calcium abundances have also been calculated using the same method and
  are found to be in close agreement with the values derived from the
  line-to-continuum technique (Lemen et al., 1990 and Sylwester et al.,
  1990). The variation of iron and calcium abundances is compared. A
  correction to the ionization balance for iron is proposed.

---------------------------------------------------------
Title: The SOLAR-A Bragg Crystal Spectrometer (Extended Abstract)
Authors: Culhane, J. L.; Hiei, E.; Bentley, R. D.; Brown, C. M.;
   Doschek, G. A.; Feldman, U.; Lang, J.; Watanabe, T.
1991LNP...387...22C    Altcode: 1991fpsa.conf...22C
  No abstract at ADS

---------------------------------------------------------
Title: The physics of solar flares. Proceedings.
Authors: Culhane, J. L.; Jordan, C.
1991psf..conf.....C    Altcode:
  First published in Philos. Trans. R. Soc. London, Ser A, Vol. 336,
  No. 1643, p. 321 - 495 (1991). The purpose of this volume is to review
  the contribution of the three spacecraft (P78-1, SMM, and Hinotori)
  to the study of solar flares. It also includes discussions of the
  current theoretical basis of some aspects of solar flares (including
  magnetic energy conversion).

---------------------------------------------------------
Title: Plasma diagnostics with the Solar-A Bragg Crystal Spectrometer
Authors: Culhane, J. L.; Hiei, E.; Bentley, R. D.; Brown, C. M.;
   Doschek, G. A.; Feldman, U.; Lang, J.; Watanabe, T.
1991AdSpR..11e..77C    Altcode: 1991AdSpR..11...77C
  A Bragg Crystal spectrometer is one of the instruments on the Solar-A
  mission. Using bent crystals, the spectrometer will observe the
  resonance line complexes of the H-like Fe XXVI, and He-like Fe XXV
  and Ca XIX ions with a sensitivity 5 to 10 times that of the SMM Bent
  Crystal Spectrometer. It will also study the lower temperature lines
  of He-like S XV. The improved sensitivity will allow observations
  much earlier in the impulsive phase of flares than has previously been
  possible. The new observations should help to answer questions about
  plasma heating and dynamics. As well as providing information on line
  profiles and shifts, the selected spectral lines will also provide
  electron temperature and emission measure estimates over a range from
  5 to 50 MK. The onboard microprocessor will permit spectral resolution
  to be traded against time resolution during an observation.

---------------------------------------------------------
Title: Mullard Space Science Laboratory, University College
    London. Report for the period 1988 August 1 to 1989 July 31.
Authors: Culhane, J. L.
1990QJRAS..31..191C    Altcode: 1990QJRAS..31..191.
  No abstract at ADS

---------------------------------------------------------
Title: The X-ray orbital lightcurve of TY Pyx : a 3.2-day eclipsing
    RS CVn system.
Authors: Culhane, J. L.; White, N. E.; Shafer, R. A.; Parmar, A. N.
1990MNRAS.243..424C    Altcode:
  An Exosat observation of one orbital cycle of the eclipsing 3.2-d
  RS CVn system TY Pyx is reported. This system contains two almost
  identical GV stars, which is unusual because most RS CVns contain F or
  G main-sequence star and a K subgiant. The X-ray light curves of the
  primary and secondary eclipses are different above and below 1 keV. At
  lower energies a sharp eclipse is seen, but at higher energies it is
  absent. This confirms earlier observations that the 1.5-4.0 x 10 to
  the 7th K emission from the RS CVn systems is not eclipsed and comes
  from an extended region, whereas the 7 x 10 to the 6th K emission
  comes from more compact solarlike active regions. Modeling the X-ray
  eclipse detected at low energies requires two emission regions, one
  on each star, covering less than 20 percent of the stellar surface. To
  avoid a strong orbital modulation caused by both regions being either
  simultaneously visible, or not visible, they must be located 180 deg
  apart in longitude. The derived longitudes are 0 and 180 deg; i.e.,
  they point at each other on the inward faces of the two stars.

---------------------------------------------------------
Title: X-Ray Eclipse Mapping of AR Lacertae
Authors: White, N. E.; Shafer, R. A.; Horne, K.; Parmar, A. N.;
   Culhane, J. L.
1990ApJ...350..776W    Altcode:
  Exosat data of the binary cycle of the eclipsing RS CVn system AR Lac
  are studied. The data reveal that at energies of less than 1 ke V a
  factor of 2 intensity modulation is detected and at energies greater
  than 1 ke V no orbital modulation is observed. The chi-squared and
  maximum entropy methods are used to model low-energy modulation. The
  relation between the low-temperature component and height is
  examined. It is observed that 50 pct of the X-ray flux comes from a
  surface area covering up to 16 pct of the K star and 25 pct of the G
  star and that peak coronal pressure is about 100 dyne/sq cm.

---------------------------------------------------------
Title: The Decay Phase of Three Large Solar Flares
Authors: Fludra, A.; Bentley, R. D.; Culhane, J. L.; Jakimiec, J.;
   Lemen, J. R.; Sylwester, J.; Moorthy, S. T.
1990PDHO....7..266F    Altcode: 1990ESPM....6..266F; 1990dysu.conf..266F
  No abstract at ADS

---------------------------------------------------------
Title: Comments on the future observatories and their X-ray
    spectroscopy capability
Authors: Culhane, J. L.
1990hrxr.conf..281C    Altcode: 1990IAUCo.115..281C
  The use of planned space X-ray observatories with resolving
  power E/Delta E greater than 25 at photon energies above 5 keV for
  spectroscopic observations is discussed. Particular attention is given
  to the types of instruments capable of the resolution required (CCDs,
  Bragg spectrometers, microcalorimeters, and transmission gratings);
  moderate-scale satellites planned to follow the Rosat mission (the
  Soviet Spectrum-X, the ESA X-ray telescopes, the Japanese Astro-D,
  and the German Spectrosat); and the large X-ray observatories (NASA
  AXAF and ESA XMM). Tables of numerical specifications and sample
  spectra obtained with the Einstein Observatory Focal-Plane Crystal
  Spectrometer and the SMM X-ray Polychromator are provided.

---------------------------------------------------------
Title: An EXOSAT observation of spectral variability from the RS
    CVn binary AR Lac
Authors: White, N. E.; Parmar, A. N.; Shafer, R. A.; Horne, K.;
   Culhane, J. L.
1990hrxr.conf..176W    Altcode: 1990IAUCo.115..176W
  The eclipsing RS CVn system AR Lac (G2IV + K0IV) has been
  observed continuously for one 2-day binary cycle with the Exosat
  observatory. Below 1 keV, a factor of two intensity modulation is
  seen with a flat bottomed minimum around the time of primary eclipse
  and a shallow dip preceeding primary eclipse. Above 1 keV, where only
  emission with temperatures greater than 10 exp 7 K would be detected,
  no orbital modulation or eclipse is seen. This suggests that the
  greater than 20 million degree emission comes from a large region,
  comparable in size to the binary separation. The modulation in the
  less than 1 keV lightcurve has been modeled by chi-squared fitting to
  X-ray bright spots and by using maximum entropy deconvolution. The
  lower temperature emission is found to originate in compact regions
  with a pressure and temperature similar to that of the flaring sun.

---------------------------------------------------------
Title: Book Review: X-ray detectors in astronomy. / CUP, 1989
Authors: Culhane, J. L.
1989Obs...109..244C    Altcode: 1989Obs...109..244F
  No abstract at ADS

---------------------------------------------------------
Title: X-ray Eclipse Mapping of Stellar Activity in RSCV<SUB>n</SUB>
    Systems with EXOSAT
Authors: Culhane, J. L.; White, N. E.; Parmar, A. N.; Shafer, R. A.;
   Harre, K.
1989BAAS...21.1083C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Mullard Space Science Laboratory. University College
    London. Report for the period 1987 August 1 to 1988 July 31.
Authors: Culhane, J. L.
1989QJRAS..30..253C    Altcode: 1989QJRAS..30..253.
  No abstract at ADS

---------------------------------------------------------
Title: Chromospheric explosions.
Authors: Doschek, G. A.; Antiochos, S. K.; Antonucci, E.; Cheng,
   C. -C.; Culhane, J. L.; Fisher, G. H.; Jordan, C.; Leibacher, J. W.;
   MacNiece, P.; McWhirter, R. W. P.; Moore, R. L.; Rabin, D. M.; Rust,
   D. M.; Shine, R. A.
1989epos.conf..303D    Altcode:
  The work of this team addressed the question of the response and
  relationship of the flare chromosphere and transition region to the
  hot coronal loops that reach temperatures of about 10<SUP>7</SUP>K
  and higher. Flare related phenomena such as surges and sprays were
  also discussed. The team members debate three main topics: 1) whether
  the blue-shifted components of X-ray spectral lines are signatures of
  "chromospheric evaporation"; 2) whether the excess line broadening of UV
  and X-ray lines is accounted for by "convective velocity distribution"
  in evaporation; and 3) whether most chromospheric heating is driven by
  electron beams. These debates illustrated the strengths and weaknesses
  of our current observations and theories.

---------------------------------------------------------
Title: A combined radio and X-ray observation of Algol.
Authors: van den Oord, G. H. J.; Kuijpers, J.; White, N. E.; van der
   Hulst, J. M.; Culhane, J. L.
1989A&A...209..296V    Altcode:
  The detection of Algol (Beta Per) at 1.4 GHz is reported. The eclipsing
  phase of Algol has been observed in radio and at X-ray energies. The
  radio emission is explained as synchrotron radiation from electrons
  with energies of about 1 MeV. The magnetic field strength is of the
  order of tens of Gauss. The radio and X-ray emission are cospatial but
  the energy in the radio component is 1,000,000 times smaller than that
  of the X-ray component. The simultaneous observation indicates that
  an energetic particle component can be present in a quiescent X-ray
  emitting corona.

---------------------------------------------------------
Title: CDS: The Coronal Diagnostic Spectrometer
Authors: Patchett, B. E.; Harrison, R. A.; Sawyer, E. C.; Aschenbach,
   B.; Culhane, J. L.; Doschek, G. A.; Gabriel, A. H.; Huber, M. C. E.;
   Jordan, C.; Kjeldseth-Moe, O.
1988sohi.rept...39P    Altcode:
  The prime objective of the Coronal Diagnostic Spectrometer (CDS) is to
  obtain intensity ratios of selected extreme-ultraviolet line pairs, with
  spatial and temporal scales appropriate to the fine-scale features of
  the solar atmosphere. This will be done simultaneously across a large
  portion of the solar atmosphere. From this, density and temperature
  information will be derived which coupled with a modest capability for
  the detection of flows will be used to study the energy and mass balance
  of the atmosphere. Understanding the heating of the solar corona and the
  acceleration of the solar wind are the ultimate goals of this research.

---------------------------------------------------------
Title: The Bragg Crystal Spectrometer Experiment on SOLAR-A
Authors: Hiei, E.; Culhane, J. L.; Doschek, G. A.
1988BAAS...20..710H    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: X-ray spectroscopy of high temperature plasma in solar flares
Authors: Culhane, J. L.
1988AdSpR...8k..67C    Altcode: 1988AdSpR...8...67C
  X-ray spectroscopic observations with high wavelength resolution provide
  information on plasma density, temperature and emission measure together
  with bulk and turbulent velocity data for the hot plasma. Observations
  carried out during the 1980 solar maximum with spectrometers on the
  SMM, P78-1 and Hinotori spacecraft will be reviewed with emphasis on
  the advances made possible by these missions. During the next solar
  maximum, flare studies with particular emphasis on the impulsive phase
  will be undertaken by the Japanese Solar-A mission. Those instruments
  designed to study the hot plasma will be described and their proposed
  role in clarifying the nature of the impulsive phase discussed.

---------------------------------------------------------
Title: CHASE Observations of the Solar Corona
Authors: Breeveld, E. R.; Culhane, J. L.; Norman, K.; Parkinson,
   J. H.; Gabriel, A. H.; Lang, J.; Patchett, B. E.; Payne, J.
1988ApL&C..27..155B    Altcode:
  The Coronal Helium Abundance Spacelab Experiment (CHASE) was undertaken
  to make a precision measurement which could have significant
  cosmological implications. The CHASE UV-spectrometer was flown
  successfully on the Spacelab 2 mission. Observations of many spectral
  lines were made including the Lyman-alpha lines of hydrogen at 121.6
  nm and of ionized helium at 30.4 nm both on the solar disk where the
  lines are excited, and in the corona, where the lines are formed by
  resonance scattering of the disk radiation. When the instrument scatter
  function has been measured, these observations will enable the solar
  helium abundance to be measured.

---------------------------------------------------------
Title: Development of X-ray calorimetric detectors and data processing
    techniques at London University.
Authors: Hepburn, I. D.; Ade, P. A. R.; Griffin, M. J.; Holland,
   W. S.; Culhane, J. L.; Kessel, R.; Walton, D. M.
1988ltdd.conf..165H    Altcode: 1988ltdn.conf..165H
  The authors describe research in progress in which they have designed
  and constructed thermal detectors which are capable of measuring
  the small pulses of energy produced by the absorption of X-rays in
  the 1 - 10 keV energy range. At present these detectors are operated
  at <SUP>3</SUP>He temperature (0.34K), which results in an inherent
  energy resolution of 673 eV. The authors also present a preliminary
  discussion on the possible processing techniques that can be applied
  to the raw data; such processing improves the achievable resolution
  to around 350 eV.

---------------------------------------------------------
Title: X-ray objective grating spectrograph.
Authors: Catura, R. C.; Stern, R. A.; Cash, W.; Windt, D. L.; Culhane,
   J. L.; Lappington, J.; Barnsdale, K.
1988SPIE..830..204C    Altcode:
  A grazing incidence X-ray spectrograph for investigating the spectra
  of cosmic X-ray sources is described. The overall instrument design
  is reviewed, and the key components of the spectrograph, including the
  gratings, telescope, and detector, are examined. Preliminary performance
  measurements are reported and plans for the instrument are addressed.

---------------------------------------------------------
Title: An EXOSAT observation of 1.5 orbital cycles of the 0.7 day
    short-period RS CVn system ER Vul.
Authors: White, N. E.; Culhane, J. L.; Parmar, A. N.; Sweeney, M. A.
1987MNRAS.227..545W    Altcode:
  Two Exosat observations of the short-period 0.7-day eclipsing RS Cvn
  binary system ER Vul are reported. The first observation in October
  1984, lasted for 3 hr, while the second in May 1985, covered 1.5
  orbital cycles. The overall counting rate decreased by a factor of
  about 2 in the 6 months separating the two observations. No strong
  orbital modulation of the X-ray flux was evident, nor were any deep
  eclipses seen. The spectrum measured in the 0.05-6 keV band was well
  fitted by a two-component thermal plasma model with temperaures of
  6 and 40 million degrees. The failure to detect any strong orbital
  modulation indicates for both temperature components either loop
  heights larger than a stellar radius, or more compact loops that
  are uniformly distributed as a function of longitude. The failure to
  detect deep eclipses cannot convicingly be used to distinguish these two
  possibilities because only latitudes greater than 10 deg are occulted,
  although there was some evidence for a 10-20 percent occultation of
  the low-energy light curve at secondary optical eclipse.

---------------------------------------------------------
Title: EXOSAT observations of the SNR PKS 1209-52.
Authors: Kellett, B. J.; Branduardi-Raymont, G.; Culhane, J. L.;
   Mason, I. M.; Mason, K. O.; Whitehouse, D. R.
1987MNRAS.225..199K    Altcode:
  Spatially resolved spectroscopy of the supernova remnant PKS 1209-52
  and the point source within it is presented, based on observations
  made with the EXOSAT PSD detector. The authors find evidence that
  the shock front of the supernova remnant is interacting with an
  interstellar cloud. The data further indicate that the whole remnant
  is not in pressure equilibrium. The average PSD spectrum of the SNR is
  fitted with a Raymond &amp; Smith line-emission model: the best-fit
  temperature is 1.7×10<SUP>6</SUP>K and the absorbing column is
  1.4×10<SUP>21</SUP>cm<SUP>-2</SUP>. The spectrum of the point source
  is harder than that of the supernova remnant, but requires a similar
  absorbing column. The authors suggest that this source is the neutron
  star remnant of the supernova explosion.

---------------------------------------------------------
Title: The X-Ray Orbital Lightcurve of AR Lac
Authors: White, N. E.; Shafer, R.; Parmar, A. N.; Culhane, J. L.
1987LNP...291..521W    Altcode: 1987csss....5..521W; 1987LNP87.291..521W
  Using the EXOSAT observatory we have obtained the X-ray light curve
  of the 2 day eclipsing RS CVn binary system AR Lac continuously around
  one complete binary cycle. A deep minimum centered on primary eclipse
  is seen in the low energy telescope (0.05-2.0 keV), whereas the ME
  (1.0-10.0 keV) flux remained constant. This shows that the 5-7 million
  and the 15-30 million degree components found by Swank et al. (1981)
  using the Einstein SSS originate in two distinct regions. The failure
  to detect an eclipse in the ME indicates that the 15-30 million degree
  plasma comes from a region larger than the radii of the underlying
  stars. Modelling of the X-ray light curve shows that the lower
  temperature emission originates from two localized regions on the G
  star at longitudes of 3° and 150° with azimuthal angular extents
  of ∼60°. The measured volume can be combined with the RTV scaling
  relation to infer loop heights of 7,000 km. In addition there is a
  large structure on the K star that extends from a longitude of 180°
  to 270° with a height of order one stellar radius; this (probably)
  contains much hotter plasma with a temperature of 15-20 million degrees.

---------------------------------------------------------
Title: Chromospheric explosions
Authors: Doschek, G. A.; Antiochos, S. K.; Antonucci, E.; Cheng,
   C. -C.; Culhane, J. L.; Fisher, G. H.; Jordan, C.; Leibacher, J. W.;
   MacNeice, P.; McWhirter, R. W. P.
1986epos.conf..4.1D    Altcode: 1986epos.confD...1D
  Three issues relative to chromospheric explosions were debated. (1)
  Resolved: The blue-shifted components of x-ray spectral lines are
  signatures of chromospheric evaporation. It was concluded that
  the plasma rising with the corona is indeed the primary source of
  thermal plasma observed in the corona during flares. (2) Resolved:
  The excess line broading of UV and X-ray lines is accounted for by a
  convective velocity distribution in evaporation. It is concluded that
  the hypothesis that convective evaporation produces the observed
  X-ray line widths in flares is no more than a hypothesis. It is
  not supported by any self-consistent physical theory. (3) Resolved:
  Most chromospheric heating is driven by electron beams. Although it
  is possible to cast doubt on many lines of evidence for electron
  beams in the chromosphere, a balanced view that debaters on both
  sides of the question might agree to is that electron beams probably
  heat the low corona and upper chromosphere, but their direct impact
  on evaporating the chromosphere is energetically unimportant when
  compared to conduction. This represents a major departure from the
  thick-target flare models that were popular before the Workshop.

---------------------------------------------------------
Title: Early results from the CHASE experiment flown on Spacelab 2.
Authors: Gabriel, A. H.; Patchett, B. E.; Lang, J.; Culhane, J. L.;
   Norman, K.; Parkinson, J. H.
1986JBIS...39..207G    Altcode:
  The Coronal Helium Abundance Spacelab Experiment (CHASE), flown on
  the Space Shuttle as part of the Spacelab 2 payload on July 29, 1985,
  was designed to measure the abundance of helium relative to hydrogen;
  a measure of this quantity is an important verification of models
  of the birth of the universe. In addition to this primary objective,
  the instrument was used to study the properties of the corona. CHASE
  instrumentation and operation are described, and preliminary data are
  examined. The instrument consists of a grazing incidence spectrometer
  covering the wavelength range of 150 A to 1350 A, illuminated by a
  grazing incidence telescope of 28 cm focal length; the spectrometer
  module incorporated the mechanism control electronics, detector
  preamplifiers, high voltage supplies and a sensor to indicate the
  offset from the sun center. Spectral lines are indicated schematically,
  and it is noted that there is no problem separating the He II line from
  the nearby Si XI line. Mapping of large areas of the sun revealed that
  at low temperature, two bright points are apparent, whereas at high
  temperature, these coalesce to form a single bright patch in the center.

---------------------------------------------------------
Title: Results from the Coronal Helium Abundance Spectrometer
Authors: Culhane, J. L.
1986BAAS...18..672C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: EXOSAT Observations of AR Lac: X-Ray Light Curve Reconstruction
    &amp;the 3D Structure of Stellar Active Regions
Authors: Shafer, R. A.; White, N. E.; Parmar, A. N.; Culhane, J. L.
1986BAAS...18..704S    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: X-ray observations and the structure of stellar coronae.
Authors: Culhane, J. L.
1986Obs...106....5C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The soft X-ray spectrum of NGC 4151.
Authors: Pounds, K. A.; Warwick, R. S.; Culhane, J. L.; de Korte,
   P. A. J.
1986MNRAS.218..685P    Altcode:
  EXOSAT observations of the Seyfert galaxy NGC 4151 over the period 1983
  July - 1984 April have revealed a steeply decreasing flux in the 2 -
  10 keV band. Other observations have shown that this coincided with
  a fall in the whole infrared-to-ultraviolet continuum and a marked
  weakening of the broad emission lines. The X-ray spectral shape,
  however, remained unchanged, although - in accord with previous
  measurements - a power-law spectrum attenuated with a simple column of
  cold gas does not provide a satisfactory spectral fit below about 3 keV,
  where a lower relative opacity is required. Inclusion of additional
  low energy data from the EXOSAT telescopes allows the modelling of the
  absorbing column to be improved and reveals a second, separate, soft
  X-ray spectral component. It is suggested that this soft component
  may be thermal emission from a hot intercloud medium in the narrow
  emission line region.

---------------------------------------------------------
Title: An EXOSAT Observation of Quiescent and Flare Coronal X-Ray
    Emission from Algol
Authors: White, N. E.; Culhane, J. L.; Parmar, A. N.; Kellett, B. J.;
   Kahn, S.; van den Oord, G. H. J.; Kuijpers, J.
1986ApJ...301..262W    Altcode:
  X-ray emission from the Algol system is believed to originate in a
  corona associated with the K star. The authors have used the EXOSAT
  Observatory to make a 35 hr continuous observation centered on the
  occultation of the K star by the B star primary. The spectrum of
  the quiescent emission in the 1 - 10 keV band gives a temperature of
  2.5×10<SUP>7</SUP>K. This spectrum, extrapolated to lower energies,
  can account for more than 80% of the observed count rate. No obvious
  X-ray eclipse was seen. An X-ray flare was detected with a rise time
  of ≡1700 s and an exponential decay of ≡7000 s. The 0.1 - 10 keV
  peak luminosity was 1.4×10<SUP>31</SUP>ergs s<SUP>-1</SUP>. The peak
  temperature was 6×10<SUP>7</SUP>K, with an iron K line confirming
  the thermal character of the emission.

---------------------------------------------------------
Title: Chromospheric explosions.
Authors: Doschek, G. A.; Antiochos, S. K.; Antonucci, E.; Cheng,
   C. -C.; Culhane, J. L.; Fisher, G. H.; Jordan, C.; Leibacher, J. W.;
   MacNiece, P.; McWhirter, R. W. P.; Moore, R. L.; Rabin, D. M.; Rust,
   D. M.; Shine, R. A.
1986NASCP2439....4D    Altcode:
  The work of this team addressed the question of the response and
  relationship of the flare chromosphere and transition region to the
  hot coronal loops that reach temperatures of about 10<SUP>7</SUP>K
  and higher. Flare related phenomena such as surges and sprays are
  also discussed. The team members debated three main topics: 1. whether
  the blue-shifted components of X-ray spectral lines are signatures of
  "chromospheric evaporation"; 2. whether the excess line broadening of UV
  and X-ray lines is accounted for by "convective velocity distribution"
  in evaporation; and 3. whether most chromospheric heating is driven
  by electron beams.

---------------------------------------------------------
Title: High resolution imaging with a solid scintillator-based
    detector
Authors: Schwarz, H. E.; Lapington, J. S.; Culhane, J. L.
1986SPIE..597..397S    Altcode:
  A prototype optical image intensifier is coupled to a phosphor-coated
  fibre optic to provide an imaging soft X-ray detector. The authors
  show that high quantum efficiency is combined with high position
  resolution and some energy resolution. They estimate the dark current
  and particle background rejection factors of this detector and discuss
  its suitability for space applications such as X-ray astronomy.

---------------------------------------------------------
Title: Soft X-ray observations of high-velocity features in the 29
    June 1980 flares
Authors: Bentley, R. D.; Lemen, J. R.; Culhane, J. L.; Phillips,
   K. J. H.
1986A&A...154..255B    Altcode:
  During the impulsive phase of two flares on 29 June 1980, short
  lived emission line features have been observed in soft X-rays,
  near the resonance lines of Fe XXV and Ca XIX, by the Bent Crystal
  Spectrometer on the Solar Maximum Mission. They are coincident with hard
  X-ray bursts and with the onset of Hα sprays. They appear to result
  from a different type of phenomenon from the unresolved blue-shifted
  component from the resonance lines reported by Feldman et al. (1980)
  and Antonucci et al. (1982). The authors believe that these discrete
  line features are due to Doppler-shifted resonance line emission from
  well collimated, moving plasma with large line-of-sight velocities.

---------------------------------------------------------
Title: X-ray instrumentation in astronomy
Authors: Culhane, J. L.
1986xria.conf.....C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: X-ray instrumentation in astronomy. Proceedings of a conference
    held at Cannes, France, 2 - 4 December 1985.
Authors: Culhane, J. L.
1986SPIE..597.....C    Altcode:
  Recent developments in X-ray and EUV astronomical instrumentation are
  discussed in reviews and reports. Topics examined include optical
  systems for the NASA Advanced X-ray Astrophysics Facility (AXAF),
  specialized X-ray systems, advanced X-ray optics, gas-filled X-ray
  detectors, instrumentation for spectrometry on AXAF, X-ray and EUV
  spectrometers, microchannel plate detectors, and solid-state detectors.

---------------------------------------------------------
Title: EXOSAT observations of a strong soft X-ray excess in MKN 841.
Authors: Arnaud, K. A.; Branduardi-Raymont, G.; Culhane, J. L.;
   Fabian, A. C.; Hazard, C.; McGlynn, T. A.; Shafer, R. A.; Tennant,
   A. F.; Ward, M. J.
1985MNRAS.217..105A    Altcode:
  EXOSAT observations of the spectrum of the Seyfert 1 galaxy MKN 841
  show that it is well-fitted by a power law of photon index 1.6,
  similar to that of other Seyferts, and a large additional soft
  component. The X-ray luminosity over the observed band exceeds
  4×10<SUP>44</SUP>erg s<SUP>-1</SUP>. A single-temperature blackbody
  fit to the soft X-rays and the short-wavelength ultraviolet continuum
  gives a luminosity of 2×10<SUP>46</SUP>erg s<SUP>-1</SUP> while an
  accretion disc spectrum fitted to the same points gives a luminosity
  of 4.3×10<SUP>45</SUP>erg s<SUP>-1</SUP>. The flux measured by both
  the EXOSAT low- and medium-energy instruments exhibits 12 per cent
  amplitude variability on a time-scale of one day.

---------------------------------------------------------
Title: X-ray applications of deep-depletion CCDs.
Authors: Walton, D. M.; Culhane, J. L.; Stern, R. A.; Catura, R. C.
1985ESASP.239..291W    Altcode: 1985cxrs.work..291W
  Results are presented demonstrating the successful use of deep-depletion
  CCDs as single photon X-ray detectors. CCDs as focal plane X-ray
  detectors for X-ray astronomy offer high spatial resolution combined
  with good energy resolution. The importance of deep-depletion CCDs is a
  significantly higher X-ray quantum efficiency than that of conventional
  CCDs. The application of CCDs to an X-ray astronomy mission such as
  XMM is described.

---------------------------------------------------------
Title: An imaging optical/UV monitor for XMM.
Authors: Mason, K. O.; Allington-Smith, J.; Culhane, J. L.; Cordova,
   F. A.; Priedhorsky, W. C.; Murdin, P. G.; Bingham, R.; Margon, B.;
   Hutchings, J. B.
1985ESASP.239..255M    Altcode:
  The authors propose that a sensitive instrument affording photometry
  and spectroscopy at optical and ultraviolet wavelengths could be added,
  with minimal expenditure, to the complement of AXAF detectors. An AXAF
  Imaging Optical/UV Monitor would enable simultaneous X-ray, optical,
  and ultraviolet data to be obtained for every AXAF field.

---------------------------------------------------------
Title: Capabilities of spectroscopy in the context of X-ray astronomy
    in the1990's.
Authors: Culhane, J. L.
1985ESASP.239....5C    Altcode: 1985cxrs.work....5C
  The mission philosophies and parameters of the NASA AXAF and ESA XMM
  X-ray astronomy observatories are reviewed. The scientific topics that
  require an observatory of the XMM class are outlined and the relevance
  of angular and spectral resolution to these aims is discussed. The
  observing requirements of surveys and point source detection; galatic
  clusters; active galatic nuclei; normal galaxies and halos; stars;
  X-ray binaries; supernova remnants; and the interstellar medium are
  considered.

---------------------------------------------------------
Title: The soft X-ray spectrum of NGC 4151
Authors: Pounds, K. A.; Warwick, R. S.; Culhane, J. L.; de Korte, P.
1985SSRv...40..585P    Altcode: 1985SSRev..40..585P
  EXOSAT observations of the Seyfert galaxy NGC 4151 over the period
  July 1983 to April 1984 have revealed a decreasing flux in the 2 10
  keV band. In accord with previous measurements a power law spectrum
  attenuated with a simple column of cold gas does not provide a
  satisfactory spectral fit below ∼3 keV, where a lower relative
  opacity is required. Inclusion of additional low energy data from the
  EXOSAT telescopes allows the modelling of the absorbing column to be
  improved and reveals a second, separate, soft X-ray spectral component.

---------------------------------------------------------
Title: Position sensitive detectors for the proposed AXAF imaging
    optical/UVmonitor (AXIOM).
Authors: Allington-Smith, J. R.; Mason, I. M.; Schwarz, H. E.; Culhane,
   J. L.
1985ITNS...32..119A    Altcode:
  A description is given of the imaging detectors of the AXIOM instrument
  proposed for NASA's Advanced X-ray Astrophysics Facility (AXAF). The
  instrument is aligned with the X-ray telescope and consists of a
  diffraction limited, 30-cm aperture, telescope with redundant position
  sensitive detectors at the focus. This allows simultaneous imaging
  at optical and near UV wavelengths of the X-ray target objects. The
  proposed detectors cover a field of view of 8.5 x 8.5 sq arcmin with a
  resolution of 1 arcsec (= 50 microns FWHM). The quantum efficiency peaks
  at 30 percent and exceeds 10 percent over the wavelength range 125 to
  540 nm. The detector design consists of a bi-alkali photocathode on a
  UV-transmitting window, proximity focussed onto a microchannel plate
  intensifier with a wedge and strip readout system, and is optimized for
  high count rates both from point sources and from the sky background.

---------------------------------------------------------
Title: An EXOSAT Observation of the Morphology of the Coronal X-Ray
    Emission from Algol
Authors: White, N. E.; Culhane, J. L.; Parmar, A. N.; Kellett, B.;
   Kahn, S.; van den Oord, G. H. J.; Kuijpers, J.
1985SSRv...40...25W    Altcode:
  The X-ray emission from Algol is thought to originate in a corona
  associated with the K star in this system. We report the results of a 35
  hr continuous EXOSAT observation through secondary optical eclipse that
  was designed to measure the structure of the corona. No obvious X-ray
  eclipse was seen. The spectrum measured by the ME gives a temperature of
  2.5 × 10<SUP>7</SUP> K, consistent with the hard component previously
  seen by the Einstein SSS. The soft component previously reported by
  the SSS would only contribute at most 25% to the count rate seen in
  the LE (used with Al/P). The lack of a hard X-ray eclipse indicates the
  dimensions of the higher temperature emission region to be comparable
  to or greater than the size of the K star. An X-ray flare was detected
  with a peak luminosity of 1.4 × 10<SUP>31</SUP> erg s<SUP>-1</SUP>
  and a total duration of 8 hours. The peak temperature was 5.0 keV with
  an emission measure of 9.4 × 10<SUP>53</SUP> cm<SUP>-3</SUP>. The
  thermal nature of the flare is confirmed by the detection of an iron
  line with an EW of ∼2 keV. By equating the observed decay time of
  the flare to a known cooling law gives a dimension for the flaring
  loop of ∼0.3 stellar radii. This is much smaller than the dimensions
  of the hard component inferred from the lack of an eclipse. It seems
  probable that the flare occurred in one of the loops responsible for
  the lower temperature component seen by the SSS.

---------------------------------------------------------
Title: A simultaneous X-ray and radio observation of a flare from
    Algol
Authors: Parmar, A. N.; Culhane, J. L.; White, N. E.; van den Oord,
   G. H. J.
1985AdSpR...5c..69P    Altcode: 1985AdSpR...5...69P
  An X-ray flare was observed from Algol using the low and medium energy
  detectors on the European Space Agency's EXOSAT observatory. Spectra
  obtained during the flare are well fitted by thermal continua while
  an Fe XXV emission feature was also detected. The strength of this
  feature indicates a cosmic abundance for iron. The data indicate that
  the flare occurred in a loop of height approximately 0.25 of the K
  star radius &amp; with a magnetic field &gt;300 Gauss.

---------------------------------------------------------
Title: EXOSAT observations of SN 1006.
Authors: Jones, L. R.; Pye, J. P.; Culhane, J. L.
1985xra..conf..305J    Altcode: 1984xra..conf..305J
  Comparison of EXOSAT images of the whole of the remnant, with greater
  spatial resolution (≡30 arcsec) than obtained previously, with an
  Einstein Observatory image and a radio map, do not support a synchrotron
  origin for the soft X-ray emission.

---------------------------------------------------------
Title: Soft X-ray observations of high-velocity features in the 29
    June 1980flares.
Authors: Bentley, R. D.; Lemen, J. R.; Phillips, K. J. H.; Culhane,
   J. L.
1985RALR...85.....B    Altcode:
  During the impulsive phase of two flares on 29 June 1980, short
  lived emission line features have been observed in soft X-rays,
  near the resonance lines of Fe XXV and Ca XIX, by the Bent Crystal
  Spectrometer on the Solar Maximum Mission. They are coincident with hard
  X-ray bursts and with the onset of Hα sprays. They appear to result
  from a different type of phenomenon from the unresolved blue-shifted
  component from the resonance lines reported by Feldman et al. (1980)
  and Antonucci et al. (1982). The authors believe that these discrete
  line features are due to Doppler-shifted resonance line emission from
  well collimated, moving plasma with large line-of-sight velocities.

---------------------------------------------------------
Title: A search for X-ray emitting coronal structures in algol
Authors: Culhane, J. L.; White, N. E.; Kahn, S.; Parmar, A. N.;
   Blissett, R. J.; Kellen, B.
1985AdSpR...5c..73C    Altcode: 1985AdSpR...5...73C
  Algol was observed with the low energy imaging X-ray telescope and the
  medium energy detectors on the ESA EKOSAT spacecraft during the time
  of secondary optical eclipse when the B star passes in front of its K
  type companion. An examination of the X-ray light curves allows us to
  set preliminary lower limits to the size of an X-ray emitting corona
  associated with the K star. The medium energy detector indicates a
  continuum temperature of 24.3.10<SUP>6</SUP> K. The detection of Pe
  XVII and Pe XVIII emission lines in an objective grating spectrum of
  the source positively indicates the presence of hot coronal material.

---------------------------------------------------------
Title: SMM observations of K-alpha radiation from fluorescence of
    photospheric iron by solar flare X-rays
Authors: Parmar, A. N.; Culhane, J. L.; Rapley, C. G.; Wolfson, C. J.;
   Acton, L. W.; Phillips, K. J. H.; Dennis, B. R.
1984ApJ...279..866P    Altcode:
  High-resolution Fe K-alpha spectra near 1.94 A observed during solar
  flares with the Bent Crystal Spectrometer on the Solar Maximum Mission
  are presented. The evidence for two possible excitation mechanisms,
  electron impact and fluorescence, is examined. It is found that the
  fluorescence mechanism satisfactorily describes the results, while the
  observations do not support electron collisional excitation of the Fe
  K-alpha transitions in low ionization stages (II-XII) of iron. Using
  Bai's model of the fluorescent excitation process, the photospheric iron
  abundance relative to that of hydrogen is estimated to be 5-6 x 10 to
  the -5th. The mean height of the soft X-ray source producing the K-alpha
  fluorescence is calculated on the basis of this model for about 40 large
  flares. The solar K-alpha lines are found to be about 25 percent wider
  than those measured in the laboratory. Weak line features observed at
  wavelengths shorter than that of the K-alpha lines are discussed.

---------------------------------------------------------
Title: Mullard Space Science Laboratory - University College - London
Authors: Culhane, J. L.
1984QJRAS..25..189C    Altcode: 1984QJRAS..25..189.
  No abstract at ADS

---------------------------------------------------------
Title: EXOSAT Observations of Galactic and Extra-Galactic Sources
Authors: Mason, K. O.; Branduardi-Raymont, G.; Culhane, J. L.
1984BAAS...16..469M    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The EXOSAT imaging X-ray detectors.
Authors: Mason, I. M.; Branduardi-Raymont, G.; Culhane, J. L.; Corbet,
   R. H. D.; Ives, J. C.; Sanford, P. W.
1984ITNS...31..795M    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The X-ray spectra of active galactic nuclei.
Authors: Culhane, J. L.
1984PhST....7..134C    Altcode: 1984PhyS....7..134C
  Recent observations of the X-ray spectra of active galactic nuclei are
  reviewed. After an outline of the properties of these sources deduced
  from observations at other wavelengths, the relevance of X-ray spectra
  to our understanding of the X-ray emission mechanisms and of the
  ultimate source of energy is discussed. The emission and absorption
  features that are observed arise from the interaction of the X-rays
  from the active nuclei with the surrounding gas. Observations of these
  features are reviewed and the information they provide on the nature
  of the surrounding gas is discussed.

---------------------------------------------------------
Title: Results from the X-ray polychromator on SMM
Authors: Culhane, J. L.; Acton, L. W.; Gabriel, A. H.
1984MmSAI..55..673C    Altcode:
  Observations of the soft X-ray emitting plasma by means of the
  X-Ray Polychromator (XRP) on the Solar Maximum Mission satellite are
  described. The scientific advances achieved by use of the XRP are
  in the areas of: (1) flare morphology, (2) spectroscopy and plasma
  diagnostics, (3) chromospheric evaporation and the physics of flare
  loops, (4) studies of the microwave emission mechanisms of active
  regions, (5) the fluorescent excitation of Fe II K-alpha radiation,
  (6) measurement of variations of calcium abundance for X-ray plasmas,
  and (7) soft X-ray observations of spray transients. The findings in
  each of these areas are discussed.

---------------------------------------------------------
Title: New applications of X-ray optical techniques.
Authors: Culhane, J. L.; Cash, W.; Catura, R. C.
1984NIMPA.221..251C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Deep-depletion CCDs for X-ray astronomy.
Authors: Walton, D.; Stern, R. A.; Catura, R. C.; Culhane, J. L.
1984SPIE..501..306W    Altcode:
  The successful use of deep-depletion silicon CCDs as single photon
  X-ray detectors is described. At an X-ray energy of 5.9 keV, a quantum
  efficiency of 76 percent for a 56 micron deep, 4000 ohm-cm RCA CCD
  has been measured (three times that of a conventional CCD). The high
  X-ray quantum efficiency, high spatial resolution, and ability to
  reject charged particle background make the deep-depletion CCD one
  of the strongest contenders for focal plane instrumentation on AXAF,
  the Advance X-ray Astrophysics Facility.

---------------------------------------------------------
Title: Observations of the iron emission lines in the X-ray spectrum
    of the supernova remnant Cassiopeia A.
Authors: Manzo, G.; Peacock, A.; Taylor, B. G.; Andresen, R. D.;
   Culhane, J. L.; Catura, R. C.
1983A&A...122..124M    Altcode:
  Observations of the X-ray spectrum of the supernova remnant Cassiopeia
  A over the energy range 2-10 keV are presented. The results, obtained
  by the use of two gas scintillation proportional counter spectrometers
  flown on an Aries rocket confirm the presence of a strong blend
  of emissions lines between 6.5-7.5 keV. The principal line in the
  blend is tentatively considered to result from the 1s-2p transition
  in Hydrogen-like iron, Fe XXVI. The equivalent width of the blend is
  found to be 952 ± 143 eV consistent with the previous observations
  made with conventional proportional counters. Evidence for a weaker
  blend probably from the 1s-3p transition in Fe XXVI is also found. This
  transition, which can be clearly resolved by the spectrometer from the
  stronger blend has an equivalent width of 434 ± 102 eV. If the line
  emission does result primarily from transitions in hydrogenic iron then
  a significant component of the high temperature plasma associated with
  the shocked circumstellar material must be at temperatures above 1.5
  10<SUP>8</SUP> K.

---------------------------------------------------------
Title: X-ray Astronomy
Authors: Culhane, J. L.; Sanford, P. W.; Helfand, David J.
1983AmJPh..51..285C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The environmental background in gas-filled detectors for
    X-ray astronomy.
Authors: Mason, I. M.; Culhane, J. L.
1983ITNS...30..485M    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Application of the wedge and strip anode to position sensing
    with microchannel plates and proportional counters.
Authors: Siegmund, O. H. W.; Clothier, S.; Thornton, J.; Lemen, J.;
   Harper, R.; Mason, I. M.; Culhane, J. L.
1983ITNS...30..503S    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: High resolution large area modular array of reflectors (LAMAR)
    WolterType I X-ray telescope for Spacelab.
Authors: Catura, R. C.; Acton, L. W.; Brown, W. A.; Gilbreth, C. W.;
   Springer, L. A.; Vieira, J. R.; Culhane, J. L.; Mason, I. W.; Siegmund,
   O.; Patrick, T. J.; Sheather, P. H.; Pounds, K. A.; Cooke, B. A.;
   Evans, K.; Pye, J.; Smith, G.; Wells, A.; Spragg, J. E.; Whitford,
   C. H.; Garmire, G.; Margon, B.; Fabian, A.
1983OptEn..22..132C    Altcode:
  A Wolter Type I x-ray telescope, intended both for astronomical
  observations and to serve as a prototype module for the large area
  modular array of reflectors (LAMAR) mission, is now in definition study
  under NASA's Spacelab program. The five mirror telescope presently
  being designed is to have a blur circle radius of 20 arc sec and an
  effective area of about 400 cm2 at 1/4 keV, 200 cm2 in the 0.5 to
  2 keV range, and 50 cm2 between 2 and 5 keV. Future expansion to a
  full ten mirror telescope will approximately double these effective
  areas. A rotary interchange mechanism will allow either of two imaging
  proportional counters (IPCs) to be placed at the telescope focus; one
  operating between 0.15 and 2 keV and the other optimized for the 0.6
  to 6 keV energy range. During flight, the telescope will utilize an
  instrument pointing system for a series of observations lasting from
  six minutes to several hours. This investigation has dual objectives:
  The primary objective is scientific and involves observational study
  of galactic and extragalactic x-ray sources, extending the work of the
  Einstein Observatory to much fainter sources and to higher energies. The
  second objective is to provide an assessment of the cost and improved
  performance of utilizing Wolter Type l x-ray optics for the LAMAR
  mission and to extend the technology for producing these optics to
  still higher angular resolution and toward lower cost.

---------------------------------------------------------
Title: Solar Flares
Authors: Culhane, J. L.
1982Obs...102..116C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Impulsive Phase of Flares in Soft X-Ray Emission
Authors: Antonucci, E.; Gabriel, A. H.; Acton, L. W.; Culhane, J. L.;
   Doyle, J. G.; Leibacher, J. W.; Machado, M. E.; Orwig, L. E.; Rapley,
   C. G.
1982SoPh...78..107A    Altcode:
  Observations using the Bent Crystal Spectrometer instrument on the
  Solar Maximum Mission show that turbulence and blue-shifted motions
  are characteristic of the soft X-ray plasma during the impulsive phase
  of flares, and are coincident with the hard X-ray bursts observed
  by the Hard X-ray Burst Spectrometer. A method for analysing the
  Ca XIX and Fe XXV spectra characteristic of the impulsive phase
  is presented. Non-thermal widths and blue-shifted components in the
  spectral lines of Ca XIX and Fe XXV indicate the presence of turbulent
  velocities exceeding 100 km s<SUP>-1</SUP> and upward motions of
  300-400 km s<SUP>-1</SUP>.

---------------------------------------------------------
Title: Solar flare X-ray spectra from the Solar Maximum Mission Flat
    Crystal Spectrometer
Authors: Phillips, K. J. H.; Fawcett, B. C.; Kent, B. J.; Gabriel,
   A. H.; Leibacher, J. W.; Wolfson, C. J.; Acton, L. W.; Parkinson,
   J. H.; Culhane, J. L.; Mason, H. E.
1982ApJ...256..774P    Altcode:
  High-resolution solar X-ray spectra obtained with the Flat Crystal
  Spectrometer aboard the Solar Maximum Mission from two solar flares and
  a nonflaring active region are analyzed. The 1-22 A region was observed
  during the flare on 1980 August 25, while smaller spectral regions were
  repeatedly covered during the 1980 November 5 flare. Voigt profiles
  were fitted to spectral lines to derive accurate wavelengths and to
  resolve blends. During the August 25 flare, 205 lines were found in
  the range 5.68-18.97 A, identifications being provided for all but 40
  (mostly weak) lines. Upper limits to flare densities are derived from
  various line ratios, the hotter (about 10 to the 7th K) ions giving an
  electron density of less than 10 to the 12th per cu cm for the August
  25 flare. Other observed line ratios (e.g., in Fe XVII and Mg XII)
  indicate a need for revisions in theoretical calculations.

---------------------------------------------------------
Title: X-ray spectral classification of supernova remnants in the
    Large Magellanic Cloud
Authors: Clark, D. H.; Tuohy, I. R.; Dopita, M. A.; Mathewson, D. S.;
   Long, K. S.; Szymkowiak, A. E.; Culhane, J. L.
1982ApJ...255..440C    Altcode:
  The solid state spectrometer on the Einstein Observatory was used
  to measure the 0.6-4.5 keV X-ray spectra of six prominent supernova
  remnants in the Large Magellanic Cloud, namely, N132D, N63A, N49,
  0525-66.0, N157B, and 0540-69.3. Thermal emission is detected from the
  first four remnants and is similar in nature to that observed from young
  galactic SNRs. In contrast, N157B and 0540-69.3 have featureless X-ray
  spectra which are well described by power-law models. The present data
  support a synchrotron origin for the X-rays from N157B and 0540-69.3,
  although an alternative emission mechanism is considered for the
  latter object.

---------------------------------------------------------
Title: Individual electrons detected after the interaction of ionizing
    radiation with gases
Authors: Siegmund, O. H. W.; Culhane, J. L.; Mason, I. M.; Sanford,
   P. W.
1982Natur.295..678S    Altcode:
  The interaction of ionizing radiation (X rays or high-energy particles)
  with gases results in the creation of electron-ion pairs. For low-energy
  X rays a small cluster of primary ionization is produced close to
  the point of the initial photoionization. High-energy particles,
  however, lose a small fraction of their energy in each of a number of
  ionizing collisions resulting in a long track composed of clusters
  of ionization. We report here that the light signals emitted by a
  parallel-plate proportional counter are fast enough to allow the
  individual electrons in the ionization clusters to be resolved. By
  counting the number of electrons for low energy X ray events we
  demonstrate an improvement in energy resolution of more than a factor
  of two over conventional proportional counters.

---------------------------------------------------------
Title: The X-ray spectrometer experiment on the first spacelab flight
Authors: Andresen, R. D.; Peacock, A.; Sims, M. R.; Taylor, B. G.;
   Culhane, J. L.; Ives, J. C.; Kellock, S.; Boella, G.; Villa, G.;
   Manzo, G.; Re, S.
1982AdSpR...2d.281A    Altcode: 1982AdSpR...2..281A
  The First Spacelab Flight - scheduled for September 1983 -
  will carry a multidisciplinary payload intended to demonstrate
  that valuable scientific results can be achieved with such short
  duration missions. The payload complement includes a spectrometer
  to undertake observations of the brighter cosmic X-ray sources. The
  primary scientific objectives of this experiment are the study of
  detailed spectral features in cosmic X-ray sources and their associated
  temporal variations over a wide energy range from about 2 keV up to 80
  keV. The instrument based on the gas scintillation proportional counter,
  will have an effective area of some 180 cm<SUP>2</SUP> with an energy
  resolution of ∼ 9% FWHM at 7 keV. The key performance parameters of
  the instrument, which include calibration results and the sensitivity
  of the planned observations, are discussed.

---------------------------------------------------------
Title: A proportional counter/image intensifier system for the
    detection of low energy X-rays
Authors: Siegmund, O. H. W.; Culhane, J. L.; Mason, I. M.
1982AdSpR...2d.229S    Altcode: 1982AdSpR...2R.229S
  Proportional counters (PC's) and gas scintillation proportional counters
  (GSPC's) currently used for detection of low energy X-rays provide
  information on event position and energy. Although at 1.5 keV PC's
  have good position resolution (~ 200 μm FWHM) they have relatively
  poor energy resolution (~ 40% FWHM). Conversely GSPC's have reasonable
  energy resolution (~ 20% FWHM), but poor spatial resolution (~ 1mm
  FWHM). <P />We describe a scheme in which a parallel plate PC with
  a transparent anode deposited on a fibre optic substrate has been
  used. This allows the light emitted by electron avalanches caused by
  X-ray events in the PC to be detected by an image intensifier with
  electronic readout. Using this scheme spatial resolution better than
  that of conventional PC's should be attainable. In addition avalanches
  induced by single electrons can be resolved through observation of
  the time structure of the light flash. Using the ability to count the
  number of primary electrons created by each X-ray event, it is shown
  that energy resolution can be achieved which is comparable to that of
  the GSPC.

---------------------------------------------------------
Title: X-ray Astronomy
Authors: Culhane, J. L.; Stanford, P. W.; Cohn, Haldan
1982PhT....35f..56C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Book-Review - X-Ray Astronomy
Authors: Culhane, J. L.; Sanford, P. W.
1982S&T....63..159C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Book-Review - X-Ray Astronomy
Authors: Culhane, J. L.; Sanford, P. W.; Ray, T. P.
1982Obs...102..240C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Book-Review - X-Ray Astronomy
Authors: Culhane, J. L.; Sanford, P. W.
1982Sci...215..316C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Solar Flare X-Ray Spectra Observed with the X-Ray Polychromator
    on the Solar Maximum Mission.
Authors: Culhane, J. L.
1982uxsa.coll....1C    Altcode: 1982IAUCo..73....1C
  No abstract at ADS

---------------------------------------------------------
Title: An Astronomers Guide to EXOSAT
Authors: Culhane, J. L.
1982Obs...102R.108C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: High resolution large area modular array of reflectors /LAMAR/
    Wolter type I X-ray telescope for Spacelab
Authors: Catura, R. C.; Acton, L. W.; Brown, W. A.; Gilbreth, C. W.;
   Springer, L. A.; Vieira, J. R.; Culhane, J. L.; Mason, I. W.; Siegmund,
   O.; Patrick, T. J.
1982SPIE..284..169C    Altcode:
  The Spacelab Wolter type I X-ray telescope, which is intended for
  both astronomical observations and the functional verification of
  the future Large Area Modular Array of Reflectors (LAMAR) concept,
  comprises five mirrors and is designed to have a blur circle radius
  of 20 arcsec, with effective areas of (1) 400 sq cm at 0.25 keV,
  (2) 200 sq cm in the 0.5-2.0 keV range, and (3) 50 sq cm between
  2 and 5 keV. A rotary interchange mechanism allows either of two
  imaging proportional counters to be placed at the telescope focus. The
  telescope's primary objective is the observational study of galactic
  and extragalactic X-ray sources, extending the work of the Einstein
  Observatory to fainter sources and higher energies. Secondarily, the
  costs and performance to be expected from the use of this telescope
  type in the LAMAR mission will be assessed.

---------------------------------------------------------
Title: Fluorescent excitation of photospheric Fe K-α emission during
    solar flares
Authors: Parmar, A. N.; Culhane, J. L.; Rapley, C. G.; Phillips,
   K. J. H.; Wolfson, C. J.; Acton, L. W.; Dennis, B. R.
1982AdSpR...2k.151P    Altcode: 1982AdSpR...2..151P
  The Bent Crystal Spectrometer on the NASA Solar Maximum Mission
  satellite provides high spectral and temporal resolution observations of
  the Fe Kα lines. We have analysed spectra from almost 50 solar flares
  that occurred during 1980. These data strongly support fluorescent
  excitation of photospheric iron by photons of E &gt; 7.11 keV emitted
  by the hot coronal plasma produced during the flare. After comparison
  of the data with a model, we discuss the observed Kα line widths,
  estimates of the size of the emitting region, the height of the coronal
  source and the photospheric iron abundance.

---------------------------------------------------------
Title: The Coronal Helium Abundance Experiment on SPACELAB-2
Authors: Patchett, B. E.; Norman, K.; Gabriel, A. H.; Culhane, J. L.
1981SSRv...29..431P    Altcode:
  The Coronal Helium Abundance Spacelab Experiment, (CHASE), basically
  consists of a grazing incidence telescope and spectrometer sensitive
  over the range 150 1335 Å. Whilst aimed primarily at deriving the solar
  helium abundance from measurements of coronal resonance scattering,
  its specification has been extended in order to provide a more general
  purpose solar XUV facility. The instrument will be flown on the Spacelab
  2 Mission, currently scheduled for launch in November 1984.

---------------------------------------------------------
Title: Observations of transitions of hydrogen-like Fe XXVI in solar
    flare spectra
Authors: Parmar, A. N.; Culhane, J. L.; Rapley, C. G.; Antonucci,
   E.; Gabriel, A. H.; Loulergue, M.
1981MNRAS.197P..29P    Altcode:
  Observations of solar flare spectra over the wavelength range
  1.769-1.796 A with the Bent Crystal Spectrometer on the NASA
  Solar Maximum Mission satellite are presented. The 2P3/2, 2P1/2
  and associated satellite transitions of Fe XXVI are identified,
  their intensities and widths estimated and the results compared with
  theoretical predictions. For two spectra, which include the isolated n
  = 2 satellite features, the observations can be reproduced by plasma
  temperatures of 24,000,000 and 28,400,000 K. Linewidth measurements
  show evidence for nonthermal velocities of up to 150 km/s. Emission
  measures derived from the Fe XXVI observations are compared with those
  from lower temperature Ca XIX and Fe XXV measurements and an emission
  measure decreasing with temperature is found.

---------------------------------------------------------
Title: A European X-ray astrophysics mission
Authors: Culhane, J. L.
1981xras.nasa..183C    Altcode:
  Five instruments (Bragg Spectrometer, Large Area Proportional
  and Scintillation Counter Detectors, Wide Field X-ray Cameras and
  a Gamma-Ray Burst Monitor) are discussed and estimates of their
  performance are given. Their scientific aims are summarized and sample
  observing programmes are discussed.

---------------------------------------------------------
Title: X-ray Spectroscopy of Solar Flares
Authors: Culhane, J. L.
1981IrAJ...15...69C    Altcode:
  After a brief review of the nature of the solar corona, the X-ray output
  of solar flares is discussed in some detail with particular reference
  to emission line excitation mechanisms and to the information that can
  be obtained about the flare plasma from studies of the intensities,
  profiles and wavelengths of these lines. The X-ray crystal spectrometers
  on the NASA Solar Maximum Mission spacecraft are described and the
  interpretation of the spectra obtained with these instruments is
  discussed.

---------------------------------------------------------
Title: Extragalactic γ -rays: Discussion
Authors: Culhane, J. L.
1981RSPTA.301..602C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Measured Response of a Wolter I X-Ray Telescope Figured by
    Diamond Turning
Authors: Catura, R. C.; Bardas, D.; Brown, W. A.; Roethig, D. T.;
   Culhane, J. L.; Berthelsdorf, R.; Franks, A.
1981BAAS...13..510C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: X-ray line widths and coronal heating
Authors: Acton, L. W.; Wolfson, C. J.; Joki, E. G.; Culhane, J. L.;
   Rapley, C. G.; Bentley, R. D.; Gabriel, A. H.; Phillips, K. J. H.;
   Hayes, R. W.; Antonucci, E.
1981ApJ...244L.137A    Altcode:
  Preliminary results of spectroscopy and imaging of a solar active region
  and flare plasma in soft X-ray emission lines are presented. Observed
  X-ray line widths in a nonflaring active region are broader than the
  Doppler width corresponding to the local electron temperature. An
  analysis of 41 soft X-ray flares within a single active region reveals
  a preference for flares to occur at locations that already show
  enhanced X-ray emission and to favor magnetic complexity over high
  gradient. However, flares do not appear to be directly responsible
  for the heating and X-ray production of the active regions.

---------------------------------------------------------
Title: Observations of the limb solar flare on 1980 April 30 with
    the SMM X-ray polychromator
Authors: Gabriel, A. H.; Phillips, K. J. H.; Acton, L. W.; Wolfson,
   C. J.; Culhane, J. L.; Rapley, C. G.; Bentley, R. D.; Kayat, M. A.;
   Jordan, C.; Antonucci, E.
1981ApJ...244L.147G    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: X-Ray Emission from Active Galaxies
Authors: Hayes, M. J. C.; Bell Burnell, S. J.; Culhane, J. L.; Barr,
   P.; Sanford, P. W.; Ward, M. J.; Ives, J. C.
1981SSRv...30...39H    Altcode:
  All the Ariel V spectrometer observations of Seyfert and narrow
  emission line galaxies (including some not previously published)
  are reviewed. The X-ray spectral properties of this class of object
  are examined and the data are used to investigate the nature of the
  source. Low energy absorption and iron line emission features are
  found to be variable. The low energy absorption can be explained in
  terms of clouds in the broad line region moving across the line of
  sight. There is no correlation between X-ray luminosity and low energy
  absorption, which implies that the accreting material is different from
  the obscuring material. Variable iron line emission may be explained
  as recombination emission from highly photoionized gas, but the iron
  line emission expected at low luminosities has not been detected.

---------------------------------------------------------
Title: Ariel-Vi Observations of SCORPIO-X-1
Authors: Pollock, A. M. T.; Goodall, C. V.; Carpenter, G. F.; Bedford,
   D. K.; Cruise, A. M.; Cole, R. E.; Osborne, J. P.; Culhane, J. L.
1981SSRv...30..347P    Altcode:
  It has so far proved empirically quite successful to describe the entire
  continuum electromagnetic spectrum of Sco X-1 in terms of emission
  from an isothermal plasma at a temperature of about 50 million K. The
  need to consider multiple Compton scatterings in the calculation of
  the emergent spectrum is emphasized, noting that this process produces
  important modifications in the spectral shape at X-ray and ultraviolet
  wavelengths. It is thought that the lack of variability in the data
  discussed may be evidence of the effects of Comptonization

---------------------------------------------------------
Title: The use of diamond turned &amp; replicated wolter 1 telescopes
    for high sensitivity X-ray astronomy
Authors: Culhane, J. L.; Catura, R. C.; Pounds, K. A.; de Korte, P.;
   Franks, A.; Garmire, G. P.; Fabian, A.; Margon, B.
1981SSRv...30..581C    Altcode:
  Following the success of Einstein, it is clear that telescopes of very
  large area (∼10 cm) with angular resolution (∼20″) are needed for
  deep X-ray surveys and other observations. After a discussion of these
  objectives, which form the basis of the NASA LAMAR mission, the design
  &amp; performance of a five mirror telescope is described. The system
  was studied for possible flight on Spacelab to undertake observations
  &amp; to act as a prototype module for LAMAR. Both diamond turning
  &amp; replication methods of mirror production are discussed. The
  performance of a single Wolter I telescope with diamond turned mirrors
  will be described.

---------------------------------------------------------
Title: Spherical crystal cosmic X-ray spectrometer.
Authors: Schnopper, H. W.; Koch, L.; Cantin, M.; Mougin, B.; Rocchia,
   R.; Berthelsdorf, R. F.; Culhane, J. L.
1981SSRv...30..607S    Altcode:
  For spectral studies at energies ∼ 3keV, higher than those usually
  neglected by grazing incidence telescopes with high efficiency,
  freestanding, self-focussing, crystal arrays offer the most practical
  way to achieve adequate sensitivity through concentration. Such
  spectrometers can be designed for the entire range of energies that can
  be diffracted by crystals, ∼ 5oo eV to 10<SUP>4</SUP> eV, and, for
  energies below 3keV, can have sensitivities greater than or comparable
  with that of instruments at the focal plane of a large telescope.

---------------------------------------------------------
Title: X-ray spectra of solar flares obtained with a high-resolution
    bent crystal spectrometer
Authors: Culhane, J. L.; Rapley, C. G.; Bentley, R. D.; Gabriel,
   A. H.; Phillips, K. J.; Acton, L. W.; Wolfson, C. J.; Catura, R. C.;
   Jordan, C.; Antonucci, E.
1981ApJ...244L.141C    Altcode:
  Preliminary results obtained for three solar flares with the bent
  crystal spectrometer on the SMM are presented. Resonance and satellite
  lines of Ca XIX and XVIII and Fe XXV and XXIV are observed together
  with the Fe XXVI Lyman-alpha line. Plasma properties are deduced from
  line ratios and evidence is presented for changes of line widths
  coincident with the occurrence of a hard X-ray impulsive burst. Fe
  K-alpha spectra from a disk center and a limb flare agree with the
  predictions of a fluorescence excitation model. However, a transient
  Fe K-alpha burst observed in a third flare may be explained by the
  collisional ionization of cool iron by energetic electrons.

---------------------------------------------------------
Title: Cosmic X-Ray Observations Performed with a Gas Scintillation
    Spectrometer
Authors: Andresen, R. D.; Manzo, G.; Peacock, A.; Taylor, B. G.;
   Catura, R. C.; Culhane, J. L.; Berthelsdorf, R.
1981SSRv...30..243A    Altcode:
  Observations of the spectrum of CAS-A in the X-ray energy range 3
  to 10 keV have been made using two gas scintillation proportional
  counters flown on an Aries rocket. Analysis of the data from the 180
  second observation has resolved the emission features at ∼7 keV,
  which results from transitions in highly ionised iron.

---------------------------------------------------------
Title: X-Ray Astronomy in the Future
Authors: Culhane, J. L.
1981SSRv...30..537C    Altcode:
  It is shown how, from a beginning in 1962, X-ray observations have
  reached a position of prime importance in astronomy. It is thought
  that, in the 1980s, significant progress will come in two areas. One is
  the physics of bright X-ray sources, the other is sky surveys and the
  study of all detectable sources. For purposes of classification, bright
  sources are taken as those giving rise to fluxes greater than 1 microJy.

---------------------------------------------------------
Title: The X-Ray Imaging Telescopes on EXOSAT
Authors: de Korte, P. A. J.; Bleeker, J. A. M.; den Boggende, A. J. F.;
   Branduardi-Raymont, G.; Brinkman, A. C.; Culhane, J. L.; Gronenschild,
   E. H. B. M.; Mason, I.; McKechnie, S. P.
1981SSRv...30..495D    Altcode:
  The instrument configuration and performance characteristics of the
  X-ray imaging telescopes on EXOSAT are described. The instrument
  comprises two fully independent Wolter I imaging telescopes. Each
  telescope can be used in either of two principal modes: (i) an
  imaging mode with either a position sensitive proportional counter
  or a channel multiplier array plate in the focal plane, (ii) a
  spectrometer mode which features a 500 lines/mm and/or a 1000 lines/mm
  transmission grating as dispersive element. Preliminary results from
  the calibration of the fully integrated experiment indicate an ultimate
  angular resolution of 8.5 arc sec full width at half maximum or 17.5
  arc sec half-power beam width. The ultimate wavelength resolution in
  the spectrometer mode ranges from 1Å for wavelengths below 50Å, to
  5Å at wavelengths near 300Å. A method for estimating the telescope
  performance is given which reasonably accounts for the influence of
  the X-ray source spectrum and the degree of interstellar absorption
  on the counting statistics. A comparison between EXOSAT and the
  EINSTEIN telescope in terms of band width/resolution and minimum
  source detectability shows an enhanced potential for EXOSAT relative
  to EINSTEIN for sources with T ≦ 10<SUP>7</SUP>K and low column
  densities (&lt; 4 × 10<SUP>20</SUP>cm<SUP>-2</SUP>) and a reduced
  potential for sources with hard, or heavily cut-off, spectra.

---------------------------------------------------------
Title: Solar maximum mission experiment: Early results from the soft
    X-ray polychromator experiment
Authors: Gabriel, A. H.; Antonucci, E.; Phillips, K. J. H.; Culhane,
   J. L.; Bentley, R. D.; Parmar, A. N.; Rapley, C. G.; Acton, L. W.;
   Leibacher, J. W.; Wolfson, C. J.; Strong, K. T.; Jordan, C.
1981AdSpR...1m.267G    Altcode: 1981AdSpR...1Q.267G
  The X-Ray Polychromator experiment has been in operation on the
  SMM satellite for over three months. It is observing flares and
  active regions in the wavelength range 1Å to 23Å using a number
  of different modes. These include polychromatic imaging, high
  resolution line profiles, high dispersion spectra, and light curves
  with high time-resolution. Data are described together with some of
  the preliminary analysis and interpretation.

---------------------------------------------------------
Title: Low energy observations of Cygnus X-2 by Ariel VI
Authors: Cruise, A. M.; Cole, R. E.; Culhane, J. L.; Osborne, J.;
   Zarnecki, J.; Goodall, C. V.; Bedford, D. K.; Campbell, D. J.;
   Carpenter, G. F.; Pollock, A. M. T.; Willmore, A. P.
1981AdSpR...1m.211C    Altcode: 1981AdSpR...1..211C
  Ariel VI observations of Cygnus X-2 have revealed a rather flat spectrum
  between 0.1 and 1.5 keV with variable emission at low energy. Of the
  two conflicting interpretations of this object in terms of i) a distant
  high-luminosity (L<SUB>x</SUB> ~ 10<SUP>38</SUP> ergs s<SUP>-1</SUP>)
  binary and ii) a nearby low-luminosity (L<SUB>x</SUB> ~ 10<SUP>35</SUP>
  ergs s<SUP>-1</SUP>) degenerate dwarf system, our measurements support
  the latter.

---------------------------------------------------------
Title: Solar Maximum Mission experiment: early results from the soft
    X-ray polychromator experiment.
Authors: Gabriel, A. H.; Culhane, J. L.; Acton, L. W.; Antonucci,
   E.; Bentley, R. D.; Jordan, C.; Leibacher, J. W.; Parmar, A. N.;
   Phillips, K. J. H.; Rapley, C. G.; Wolfson, C. J.; Strong, K. T.
1981hea..conf..267G    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: High resolution large area modular array of reflectors (LAMAR)
    Wolter Type I x-ray telescope for Spacelab
Authors: Catura, R. C.; Acton, L. W.; Brown, W. A.; Gilbreth, C. W.;
   Springer, L. A.; Vieira, J. R.; Culhane, J. L.; Mason, I. W.; Siegmund,
   O.; Patrick, T. J.; Sheather, P. H.; Pounds, K. A.; Cooke, B. A.;
   Evans, K.; Pye, J.; Smith, G.; Wells, A.; Spragg, J. E.; Whitford,
   C. H.; Franks, A.; Gale, B.; Lindsey, K.; Stedman, M.; Garmire, G.;
   Margon, B.; Fabian, A.
1981SPIE..284..169C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Book-Review - X-Ray Astronomy
Authors: Culhane, J. L.; Sandford, P. W.
1981JBAA...91..611C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Low energy observations of Cygnus X-2 by Ariel VI.
Authors: Cruise, A. M.; Goodall, C. V.; Bedford, D. K.; Campbell,
   D. J.; Carpenter, G. F.; Cole, R. E.; Culhane, J. L.; Osborne, J.;
   Pollock, A. M. T.; Willmore, A. P.; Zarnecki, J.
1981hea..conf..211C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Extragalactic X-ray astronomy.
Authors: Culhane, J. L.
1981ScPrD..67..223C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Ariel V observations of A 4.8-(HR). Periodicity in the "high
    state" X-Ray spectrum of CYG X-3.
Authors: Blissett, R. J.; Mason, K. O.; Culhane, J. L.
1981MNRAS.194...77B    Altcode:
  Observations of Cygnus X-3 in 1975 May with the Ariel V proportional
  counter spectrometer reveal the existence of 4.8-hr periodic variations
  in the X-ray spectrum. Periodicity is observed in both the 2-6 keV
  continuum shape, and in the apparent energy of the iron-line, and
  occurs at a time of high mean source intensity. These results are
  compared with a similar behaviour noted by Becker et al. for the
  "low-state" spectrum. In contrast to the low-state observations,
  the data presented here do not suggest phase dependent absorption by
  material local to the source.

---------------------------------------------------------
Title: Iron line emission and variability in the X-ray spectrum of
    the Seyfert galaxy NGC 5548
Authors: Hayes, M. J. C.; Culhane, J. L.; Blissett, R. J.; Barr, P.;
   Burnell, S. J. B.
1980MNRAS.193P..15H    Altcode:
  The MSSL spectrometer on the Ariel V satellite has detected a variable
  iron emission feature in the X-ray spectrum of NGC 5548. Comparison with
  other observations indicates that both the slope and intensity of the
  continuum spectrum are variable. It is suggested that the iron emission
  is due to fluorescent excitation of the gas in the broad emission-line
  region surrounding the X-ray emitting nucleus of the galaxy.

---------------------------------------------------------
Title: Light from electron avalanches and background rejection in
    X-ray astronomy
Authors: Siegmund, O. H. W.; Sanford, P. W.; Mason, I. M.; Culhane,
   J. L.; Cockshott, R.
1980Natur.287..808S    Altcode:
  We have developed the parallel plate imaging proportional counter
  to register images of cosmic X-ray sources in the focal planes of
  X-ray telescopes<SUP>1,2</SUP>. An important factor determining the
  sensitivity of such an instrument, particularly for extended source
  studies, is the background count rate induced in the detector by the
  interaction of charged particles such as cosmic rays. This background in
  wire anode proportional counters can be reduced by applying risetime
  discrimination to the charge pulse<SUP>3</SUP>. We report here
  that a modified version of the parallel plate imaging proportional
  counter has been constructed as shown in Fig. 1a, to investigate the
  application of risetime discrimination to the scintillation pulses
  caused by the electron avalanche process<SUP>4</SUP>. We show that
  efficient background event rejection (&gt;90%) is achieved and discuss
  an application of this system for X-ray astronomy.

---------------------------------------------------------
Title: Ariel V X-ray observations of two type I Seyfert galaxies
Authors: Hayes, M. J. C.; Culhane, J. L.; Burnell, S. J. B.
1980MNRAS.192P...1H    Altcode:
  X-ray spectra of the type I Seyfert galaxies ESO 012-G21 and Markarian
  464 obtained by the proportional counter spectrometer on board Ariel
  5 are presented. ESO 012-G21 is found to have an X-ray luminosity
  of 1.5 x 10 to the 44th erg/sec at a redshift of 0.03 and a Hubble
  constant of 50 km/sec per Mpc, and is identified with the X-ray source
  3U 0055-79. An X-ray luminosity varying within a year from 3 to 0.9 x
  10 to the 44th erg/sec has been obtained for Mkn 464, and a column of
  absorbing of around 2.5 x 10 to the 23 H atoms/sq cm has been detected
  in front of the source. Evidence for a low energy cut-off in the X-ray
  spectrum of Mkn 464 is also noted.

---------------------------------------------------------
Title: A spectral study of Wray 977, the optical counterpart of the
    binary X-ray pulsar 4U 1223-62.
Authors: Parkes, G. E.; Mason, K. O.; Murdin, P. G.; Culhane, J. L.
1980MNRAS.191..547P    Altcode:
  Optical spectra of Wray 977 at dispersions of 25 and 33 Å
  mm<SUP>-1</SUP> have been obtained, and a spectral type of B2 Ia
  e derived, implying a stellar mass of 25 -3 SM<SUB>sun</SUB>. The
  P-Cygni type emission line profiles in the spectrum indicate that Wray
  977 has an extended, expanding atmosphere, and velocity progressions
  in the Balmer and strong He I series indicate that the atmosphere is
  also accelerating. The mass loss rate is probably greater than ∼3 ×
  10<SUP>-6</SUP> M<SUB>sun</SUB> yr<SUP>-1</SUP>. A distance of 1.8 ±
  0.4 kpc is derived implying that the average X-ray luminosity of 4U
  1223-62 is ∼10<SUP>36</SUP> erg <SUP>-1</SUP>. The study has shown
  that the profiles of spectral features are constant from day to day,
  contrary to the report of Vidal. The models are discussed.

---------------------------------------------------------
Title: X-ray astronomy with the Einstein observatory
Authors: Culhane, J. L.
1980Natur.284..509C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Hot Gas in Clusters of Galaxies
Authors: Culhane, J. L.
1980RSPTA.296..385C    Altcode: 1980RSLPT.296..385C
  The title of the paper indicates that our understanding of cluster
  X-ray sources has progressed considerably since their discovery in
  1971. We now believe that the extended X-ray emission that is observed
  is due to the presence of high temperature (T ≈ 10<SUP>8</SUP>
  K) gas in the clusters. The paper includes a review of the present
  status of cluster X-ray observations and an account of the evidence
  that points to brems-strahlung from hot plasma as the X-ray emission
  mechanism. Current ideas about the origin of the intracluster plasma
  and its heating mechanism are examined and the possible role of cluster
  X-raystudies in furthering out understanding of the evolution of the
  Universe is discussed.

---------------------------------------------------------
Title: The soft X-ray polychromator for the Solar Maximum Mission.
Authors: Acton, L. W.; Culhane, J. L.; Gabriel, A. H.; Bentley,
   R. D.; Bowles, J. A.; Firth, J. G.; Finch, M. L.; Gilbreth, C. W.;
   Guttridge, P.; Hayes, R. W.; Joki, E. G.; Jones, B. B.; Kent, B. J.;
   Leibacher, J. W.; Nobles, R. A.; Patrick, T. J.; Phillips, K. J. H.;
   Rapley, C. G.; Sheather, P. H.; Sherman, J. C.; Stark, J. P.; Springer,
   L. A.; Turner, R. F.; Wolfson, C. J.
1980SoPh...65...53A    Altcode:
  The 1.4-22.4 Å range of the soft X-ray spectrum includes a multitude
  of emission lines which are important for the diagnosis of plasmas
  in the 1.5-50 million degree temperature range. In particular, the
  hydrogen and helium-like ions of all abundant solar elements with Z
  &gt; 7 have their primary transitions in this region and these are
  especially useful for solar flare and active region studies. The soft
  X-ray polychromator (XRP) is a high resolution experiment working
  in this spectral region. The XRP consists of two instruments with
  a common control, data handling and power system. The bent crystal
  spectrometer is designed for high time resolution studies in lines of Fe
  I-Fe XXVI and Ca XIX. The flat crystal scanning spectrometer provides
  for 7 channel polychromatic mapping of flares and active regions in
  the resonance lines of O VIII, Ne IX, Mg XI, Si XIII, S XV, Ca XIX,
  and Fe XXV with 14″ spatial resolution. In its spectral scanning
  mode it covers essentially the entire 1.4-22.5 Å region.

---------------------------------------------------------
Title: Hot gas in clusters of galaxies.
Authors: Culhane, J. L.
1980HiA.....5..387C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The X-ray spectra of clusters of galaxies and their
    relationship to other cluster properties.
Authors: Mitchell, R. J.; Dickens, R. J.; Burnell, S. J. B.; Culhane,
   J. L.
1979MNRAS.189..329M    Altcode:
  Observations with the MSSL proportional counter spectrometer on the
  Ariel 5 satellite of the X-ray spectra of 20 candidate clusters of
  galaxies are reported. The data are compared with the results from
  the OSO 8 satellite, and the combined sample of some 30 cluster X-ray
  spectra are analyzed. Generally larger values of X-ray luminosity than
  obtained by Uhuru or the SSI are found, which, because of the larger
  field of view, may indicate significant amounts of hot gas away from
  the cluster centers. The validity of all X-ray cluster identifications
  has been examined, and sources have been classified according to
  certainty of identification. The incidence of X-ray line emission from
  the clusters has been investigated, and temperatures derived on the
  basis of an isothermal model. Relationships between X-ray, optical, and
  radio properties of the clusters have been studied. The more massive,
  centrally condensed clusters generally contain higher-temperature gas
  and have a greater luminosity than the less massive, more irregular
  clusters.

---------------------------------------------------------
Title: Soft X-ray Observations of Cygnus X2 from Ariel VI.
Authors: Cruise, A. M.; Culhane, J. L.; Osborne, J.; Cole, R.;
   Zarnecki, J.; Goodall, C. V.; Campbell, D.; Willmore, A. P.
1979BAAS...11R.794C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The X-ray spectra of clusters of galaxies
Authors: Culhane, J. L.
1979NW.....66..433C    Altcode:
  The identification of extended sources of X-ray emission
  associated with clusters of galaxies has been one of the major
  achievements of X-ray astronomy. In this paper the present situation
  regarding the identification of X-ray clusters is reviewed and
  the relationship between X-ray and optical cluster properties is
  briefly discussed. Measurements of X-ray extent have been made for
  a small number of clusters and the status of these observations is
  described. The nature of the X-ray emission process and the observations
  which have led to our present understanding of cluster X-ray production
  are examined in some detail. Observations at other wavelengths
  that are relevant to this problem are also discussed. The available
  evidence suggests that the X-ray emission is due to bremsstrahlung
  from high-temperature ( T&gt;2·10<SUP>7</SUP> K) gas that is present
  in the space between cluster galaxies. Current models of the origin
  of this gas and of its likely heating mechanism are presented.

---------------------------------------------------------
Title: Association of coronal-line and filamentary emission in
    Puppis-A.
Authors: Clark, D. H.; Murdin, P.; Zarnecki, J. C.; Culhane, J. L.
1979MNRAS.188P..11C    Altcode:
  Fe XIV coronal forbidden line emission from the supernova remnant
  Puppis-A was spectroscopically detected. Two-dimensional spectral
  data imply that the approximately 10 to the 6th K plasma coronal-line
  component forms a halo surrounding the cooler approximately 10 to the
  4th K optical filamentary component, suggesting that it originates
  from evaporated plasma from dense cloudlets rather than swept-up
  interstellar material. This result influences the interpretation of
  X-ray emission from supernova remnants.

---------------------------------------------------------
Title: NGC 4593 - a bright Seyfert galaxy with variable X-ray
    emission.
Authors: Burnell, S. J. B.; Culhane, J. L.
1979MNRAS.188P...1B    Altcode:
  Ariel 5 observations of the X-ray source 4U 1240 - 05 support
  suggestions that it should be identified with the galaxy NGC 4593
  recently found to be type 1 Seyfert. Data on the source position and
  spectrum are presented. The X-ray intensity appears to have varied by
  a factor of more than two since the Uhuru observation.

---------------------------------------------------------
Title: An investigation of the 1.9 Å feature in solar-flare X-ray
    spectra.
Authors: Parkinson, J. H.; Veck, N. J.; Ashfield, M. E. C.; Culhane,
   J. L.; Ku, W. H. -M.; Lemen, J. R.; Novic, R.; Acton, L. W.; Wolfson,
   C. J.
1979ApJ...231..551P    Altcode:
  The 1.9 A feature, observed in the X-ray spectra of three solar flares
  with the Columbia University and Lockheed Palo Alto Research Laboratory
  spectrometers on the OSO 8 satellite, is shown to be due to a blend of
  1s-2p transitions in a range of Fe ions. In the temperature range 9-16
  x -10 to the 6th K, the feature has a mean wavelength of 1.900 + or -
  0.009 A and is 0.04 A wider than a single line, indicating that the
  main contributors are Fe XIX-Fe XXII. Most of the emission originates
  from the dielectronic recombination process, and when inner-shell
  excitation is included together with normal collisional excitation, the
  observed intensity of the feature can be accounted for adequately. For
  these events, if the electron density is below approximately 10 to the
  12th/cu cm, deviations from ionization equilibrium will be significant
  for ions more highly ionized than Fe XXI.

---------------------------------------------------------
Title: The interstellar oxygen edge in the X-ray spectrum of the
    Crab Nebula.
Authors: Charles, P. A.; Kahn, S. M.; Bowyer, S.; Blissett, R. J.;
   Culhane, J. L.; Cruise, A. M.; Garmire, G.
1979ApJ...230L..83C    Altcode:
  Measurement of the X-ray spectrum of the Crab Nebula by the HEAO 1 A-2
  low-energy (0.15-3 keV) detectors is reported. The spectral restoration
  techniques described by Blissett and Cruise (1979) and Kahn and Blissett
  (1979) are used to demonstrate explicitly the existence of a 'negative'
  feature near 0.5 keV that is consistent with the edge expected due to
  absorption by interstellar oxygen. For a simple power-law model with
  photon index -2.08, the data require a column density of 3.0 + or -
  0.1 x 10 to the 21st per sq cm and an oxygen abundance of 1.0 + or -
  0.1 times the Brown and Gould (1970) value. Satisfactory fits can
  also be achieved with the more sophisticated Fireman (1974) models,
  but no model can be adjusted to fit the data without the inclusion of
  interstellar oxygen.

---------------------------------------------------------
Title: The Structure and Spectra of the X-Ray Sources in Clusters
    of Galaxies
Authors: Culhane, J. L.
1979RSPSA.366..403C    Altcode: 1979RSLPS.366..403C
  The current state of our knowledge of the Perseus cluster at radio,
  optical and X-ray wavelengths is reviewed to summarize the nature of
  cluster sources. Recent results on the X-ray structure of clusters are
  presented. Objects discussed include the Centaurus and Virgo clusters,
  Abell 1367 and Abell 478. Preliminary results of a study of 30 cluster
  X-ray spectra are reported. The derivation of the intra-cluster gas
  parameters is described and the relations between these parameters and
  other cluster properties are examined. The detection of highly ionized
  iron emission lines in the spectra of several clusters is discussed
  and estimates of iron abundance are presented.

---------------------------------------------------------
Title: Cluster iron lines and the X-ray spectrum of SC 0627-544.
Authors: Berthelsdorf, R. F.; Culhane, J. L.
1979MNRAS.187P..17B    Altcode:
  Further observations with the MSSL proportional counter spectrometer on
  the Ariel V satellite have led to the detection (at a confidence level
  of at least 99 per cent) of a highly ionized iron emission feature in
  the spectrum of the southern cluster SC 0627-544. The data obtained
  are compared with previous observations of this source made by the
  Goddard Space Flight Center's instrument on OSO-8. Iron emission
  feature detections with greater than 99 per cent confidence levels
  have now been made for five clusters of galaxies. A value of cluster
  iron abundance is deduced from these data.

---------------------------------------------------------
Title: Ariel V. Observations of Spectral Variability in Cygnus X-3
    during a High Intensity State
Authors: Blissett, R. J.; Culhane, J. L.; Mason, K. O.
1979BAAS...11..463B    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: [Fe X] and [Fe XIV] emission from Puppis A and other supernova
    remnants.
Authors: Lucke, R. L.; Zarnecki, J. C.; Woodgate, B. E.; Culhane,
   J. L.; Socker, D. G.
1979ApJ...228..763L    Altcode:
  Measurements of Fe XIV 5303-A and Fe X 6374-A forbidden emission from
  several supernova remnants are reported, and their relation to X-ray
  observations is discussed. The brightest Fe XIV forbidden-emission
  region in Puppis A is interpreted as being the result of the supernova
  shock wave's interacting with a dense cloud in the interstellar medium.

---------------------------------------------------------
Title: Performance of a flight model gas scintillation counter
    spectrometer for X-ray astronomy.
Authors: Peacock, A.; Andresen, R. D.; van Dordrecht, A.; Leimann,
   E. -A.; Manzo, G.; Taylor, B. G.; Berthelsdorf, R.; Culhane, J. L.;
   Ives, J. C.; Sanford, P. W.
1979ITNS...26..486P    Altcode:
  Results are presented on the performance of a large area gas
  scintillation proportional counter (GSPC) experiment for application
  as a spectrometer in X-ray astronomy. Two such counters will be
  launched on an Aries sounding rocket in 1979. This experiment has a
  total collecting area of 630 sq cm, and an energy resolution of 11%
  for 6 keV X-rays. The intrinsic background rejection capability with
  the aid of burst length discrimination was approximately 80% for an
  X-ray acceptance of 80% at 6 keV.

---------------------------------------------------------
Title: Cosmic X-ray telescope for ARIES rocket observations
Authors: Catura, R. C.; Acton, L. W.; Berthelsdorf, R.; Culhane,
   J. L.; Sanford, P. W.; Franks, A.
1979SPIE..184...23C    Altcode:
  A rocket-borne Wolter Type I X-ray telescope having a focal length
  of 2.3m, an entrance aperture of 66cm and a geometrical area of
  380cm2 is nearing completion. The telescope mirrors are formed by
  diamond turning their figures into forged aluminum substrates of
  5083 alloy. These diamond-turned substrates are subsequently plated
  with a thin coating of electroless nickel and polished to obtain the
  final X-ray reflecting surfaces. Details of the rocket payload, the
  X-ray telescope, its calculated response and the experience gained
  in selecting the mirror substrate alloy are discussed and the current
  status of the telescope is reviewed.

---------------------------------------------------------
Title: Some recent coronal line observations of supernova remnants.
Authors: Zarnecki, J. C.; Lucke, R. L.; Woodgate, B. E.; Culhane,
   J. L.; Socker, D.
1979xras.proc..341Z    Altcode:
  Observations of optical coronal lines from the supernova remnants Puppis
  A and N 49 in the Large Magellanic Cloud carried out at Cerro Tololo and
  the Anglo-Australian Observatory are reported. The eastern section of
  Puppis A was searched for forbidden Fe X and Fe XIV emissions in order
  to confirm the previous detection of a lower temperature component
  of the X-ray source. Strong forbidden Fe XIV emission was detected
  in one region consistent with the position of the previously observed
  soft X-ray component, implying a cool localized component, possibly a
  relatively dense interstellar cloud interacting with the expanding shock
  front, superimposed on a more extended hotter region. The spectrum of
  N 49 showed a broad feature at 5303 A, identified with the forbidden
  Fe XIV line. Predictions of X-ray fluxes assuming a temperature of
  2 x 10 to the 6th K and a density behind the shock front of 4/cu cm
  for hydrogen densities of zero and 10 to the 21st/sq cm lead to the
  suggestion that X-ray observations of N 49 may prove worthwhile.

---------------------------------------------------------
Title: The nature of the X-ray source associated with the Vela pulsar.
Authors: Mason, K. O.; Culhane, J. L.
1978MNRAS.185..673M    Altcode:
  Summary. Investigation of the X-ray source associated with PSR0833 45,
  using data from the Copernicus and Ariel V satellites, indicates a
  significant enhancement in surface brightness within 6 arcmin of the
  pulsar, while confirming that the emission is extended.

---------------------------------------------------------
Title: The X-ray structure of supernova remnants II. Puppis-A.
Authors: Charles, P. A.; Culhane, J. L.; Zarnecki, J. C.
1978MNRAS.185P..15C    Altcode:
  Summary. We report here the final results of processing the Copernicus
  0.6-1.5 keV observations of the supemova renmant (SNR) Puppis A using
  the ART algorithm. The main X-ray emitting region is resolved into four
  areas of X-ray emission, one of which is consistent with the position
  of the softer component from which 0 VIII X-ray and Fe xiv coronal
  line emission has recently been observed. The X-ray spatial structure
  in Puppis A is briefly discussed in terms of current SNR models.

---------------------------------------------------------
Title: Coronal lines in SNR spectra.
Authors: Murdin, P.; Clark, D. H.; Culhane, J. L.
1978MmSAI..49..583M    Altcode:
  Of the three components of the extended remnant of a supernova, the
  thin filament and the peripheral shell of synchrotron emission have
  been extensively studied. The third component, the shock-heated plasma,
  however, is still poorly understood. Soft X-ray emission from the plasma
  has been detected for at least eleven galactic supernova remnants
  (SNRs). If the X-rays from SNRs do indeed originate in a rarefied
  plasma with temperatures of the order of a few million degrees, the
  plasma would also be expected to emit optical coronal lines, such as
  the lambda 5303 Fe XIV line. Detection of such lines would provide for
  a sensitive estimate of plasma temperature. Evidence is presented to
  show that the reported coronal line identification in the Vela SNR is
  unproven. However, it is believed that lambda 5303 has been detected
  in N49 in the Large Magellanic Cloud, and in the Puppis A supernova.

---------------------------------------------------------
Title: A search for X-ray line emission in the spectrum of the
    Cygnus Loop.
Authors: Stark, J. P. W.; Culhane, J. L.
1978MNRAS.184..509S    Altcode:
  In connection with the reported investigation, a large area crystal
  spectrometer was constructed for a flight on a Skylark sounding rocket
  (SL 1212). The attitude control unit used was a stage V star pointing
  system. Xi Cygnus was employed as the guide star. SL 1212 was launched
  from the Woomera range, South Australia on June 11, 1977. The data
  obtained in the investigation reveal that the flux in the selected O
  VII emission lines is less than 6% of the total X-ray emission from
  the source. The result implies that the temperatures characteristic of
  the considered models are higher than has previously been determined
  from X-ray continuum studies of the source. It is possible that the
  oxygen abundance is depleted from the generally assumed cosmic value.

---------------------------------------------------------
Title: Coronal lines in supernova remnant spectra.
Authors: Murdin, P.; Clark, D. H.; Culhane, J. L.
1978MNRAS.183P..79M    Altcode:
  The detection of coronal line emission offers the possibility of
  studying the shock-heated plasma in supernova remnants (SNRs). A search
  was performed for the 5303-A forbidden Fe XIV coronal line in the
  SNRs N49 and Vela. The line was detected in the former at an intensity
  suggesting a plasma temperature in the region of 2 million K. However,
  a previously proposed detection for the Vela SNR was not confirmed.

---------------------------------------------------------
Title: X-ray and optical observations of 3U 0900-40 (Vela X-1).
Authors: Charles, P. A.; Mason, K. O.; White, N. E.; Culhane, J. L.;
   Sanford, P. W.; Moffat, A. F. J.
1978MNRAS.183..813C    Altcode:
  Copernicus and Ariel V observations of 3U0900-40 are presented. During
  1975 February a region of low intensity was observed between binary
  phase 0.5 and eclipse which was caused by an increase in photoelectric
  absorption. This low state can be interpreted as the signature of
  an accretion wake travelling across the line of sight. The source
  also showed energy-independent flaring behaviour on timescales
  of approximately 1 hr. The 283-s period measured by Copernicus in
  1975 February was 0.017 s longer than that observed by SAS-3 in 1975
  July. This is consistent with the secular decrease in period expected
  for an accreting neutron star. An upper limit of 0.004 mag is placed
  on the amplitude of broadband 283-s optical pulsations.

---------------------------------------------------------
Title: Extragalactic X-ray Astronomy
Authors: Culhane, J. L.
1978QJRAS..19....1C    Altcode:
  The identification and classification of extragalactic X-ray sources
  is discussed, with particular attention given to extended sources
  associated with clusters of galaxies and to compact sources found
  in the nuclei of active galaxies. Results obtained from the Uhuru
  spacecraft and the Ariel-V satellite provide most of the data for the
  identifications. Analysis of cluster X-ray spectra to yield information
  on the heating of gases and the nature of the intergalactic medium is
  discussed; investigation of the continuous X-ray spectra associated
  with active galaxies may clarify the problem of the energy source
  of active galaxies and quasars. Seyfert galaxies identified as X-ray
  sources and X-ray emitting components of the Perseus, Virgo, Centaurus
  and Coma clusters figure in the review.

---------------------------------------------------------
Title: X-ray spectra and variability of some Seyfert galaxies and
    other high latitude sources.
Authors: Stark, J. P.; Burnell, J. B.; Culhane, J. L.
1978MNRAS.182P..23S    Altcode:
  Observations from the Ariel V and Uhuru satellites have revealed five
  extra-galactic X-ray sources through spectrographic analysis. Such
  sources usually fall into two broad categories: galactic clusters
  and active galaxies. A best-fit model was applied to graphs of the
  sources' X-ray spectra, and the latter category was found to be more
  consistent with the obtained data. Confidence limits for the data are
  also presented.

---------------------------------------------------------
Title: An imaging soft X-ray telescope for Spacelab.
Authors: Catura, R. C.; Culhane, J. L.; de Jager, C.; Garmire, G. P.;
   Novick, R.
1978nisa.symp..247C    Altcode: 1978nisa.conf..247C
  No abstract at ADS

---------------------------------------------------------
Title: Solar X-ray spectroscopy with bent crystal spectrometer (BCS).
Authors: Rapley, C. G.; Culhane, J. L.; Acton, L. W.; Catura, R. C.;
   Joki, E. C.; Bakke, J. C.
1978nisa.symp..121R    Altcode: 1978nisa.conf..121R
  No abstract at ADS

---------------------------------------------------------
Title: X-Ray Observations of Clusters of Galaxies
Authors: Culhane, J. L.
1978IAUS...79..165C    Altcode: 1978lssu.conf..165C
  The situation regarding identifications of clusters of galaxies with
  X-ray sources is reviewed, and the luminosity function and possibly
  relationships between a number of cluster X-ray and optical properties
  are discussed for clusters listed in the second Ariel catalog. Recent
  X-ray observations of superclusters are also recounted along with
  cluster structural measurements by means of rocket observations with
  imaging X-ray telescopes. The present status of iron-line observations
  at 6.7 keV is described, and estimates of the iron abundance that
  result from the iron-line data are examined. The contributions of
  clusters and of X-ray emitting Seyfert galaxies to the diffuse X-ray
  background are set at 14% and 6%, respectively, for the energy range
  from 2 to 10 keV. The X-ray structures of the Perseus, Virgo, Centaurus,
  and Abell 478 clusters are briefly described. It is noted that 30 to
  40 clusters are known to be X-ray sources and that essentially all
  clusters of galaxies will probably be X-ray sources.

---------------------------------------------------------
Title: The X-Ray Spectrum and Structure of the Puppis a Supernova
    Remnant
Authors: Zarnecki, J. C.; Culhane, J. L.; Toor, A.; Seward, F. D.;
   Charles, P. A.
1978ApJ...219L..17Z    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: A focussing iron line crystal spectrometer for Spacelab.
Authors: Catura, R. C.; Culhane, J. L.; Gabriel, A. H.; Rapley, C. G.;
   Walker, A. B. C., Jr.; Woodgate, B. E.
1978nisa.symp..271C    Altcode: 1978nisa.conf..271C
  No abstract at ADS

---------------------------------------------------------
Title: The X-ray temperatures of eight clusters of galaxies and
    their relationship to other cluster properties.
Authors: Mitchell, R. J.; Ives, J. C.; Culhane, J. L.
1977MNRAS.181P..25M    Altcode:
  By combining X-ray spectral data obtained from the MSSL
  proportional-counter spectrometer on the Ariel 5 satellite with optical
  velocity-dispersion measurements for eight clusters of galaxies, it
  is demonstrated that the observed X-ray emission probably arises from
  the thermal bremsstrahlung mechanism and that the individual active
  galaxies do not play an important role in supplying energy to the
  intracluster medium. In addition, correlations between X-ray temperature
  and luminosity, between X-ray temperature and cluster radius, and
  between X-ray temperature and the mass of emitting gas are discussed.

---------------------------------------------------------
Title: Bent crystal spectrometer for solar x-ray spectroscopy
Authors: Rapley, C. G.; Culhane, J. L.; Acton, L. W.; Catura, R. C.;
   Joki, E. G.; Bakke, J. C.
1977RScI...48.1123R    Altcode:
  A bent crystal Bragg spectrometer is described which provides continuous
  and simultaneous coverage for all x-ray wavelengths within its spectral
  range. This instrument provides high spectral resolution but involves no
  precision crystal rocking or position encoding mechanisms and therefore
  may be highly ruggedized. Principles of operation are discussed and
  its application to solar x-ray spectroscopy is described.

---------------------------------------------------------
Title: A focussing iron line crystal spectrometer for Spacelab
Authors: Catura, R. C.; Culhane, J. L.; Rapley, C. G.; Gabriel, A. H.;
   Walker, A. B. C., Jr.; Woodgate, B. E.
1977cosp.meetS....C    Altcode:
  A crystal spectrometer system is described which employs conical
  focusing of 12 curved LiF crystal panels to minimize the detector
  size and reduce the background counting rate. The wavelength range
  from 1.70 to 1.98 A is covered, including the resonance lines of
  Fe XXV and Fe XXVI as well as the Fe I K-alpha line and absorption
  edge. Operation of the spectrometer is discussed, noting that diffracted
  X-rays are registered in one-dimensional position-sensitive detectors
  and that the arrival position of a photon in a detector is related
  to its wavelength due to the fixed curvature of the crystal panels
  in the dispersion plane. Some characteristics of the multianode
  position-sensitive detectors are reviewed along with the crystal
  arrangement and mounting. The instrument sensitivity is evaluated in
  relation to the strengths of 6.7-keV emission features detected by
  the Ariel 5 and OSO 8 proportional-counter spectrometers.

---------------------------------------------------------
Title: An imaging soft X-ray telescope for Spacelab
Authors: Catura, R. C.; Culhane, J. L.; De Jager, C.; Garmire, G. P.;
   Novick, R.
1977cosp.meetR....C    Altcode:
  A grazing-incidence soft X-ray telescope (SXT) of Wolter Type I
  design is described which has been proposed for use in Spacelab
  missions. The SXT consists of a four-mirror nested array of confocal
  paraboloid-hyperboloid elements and is intended to have optimal
  response in the wavelength range from 6 to 100 A (it also covers
  the range between 100 and 1000 A). Basic elements of the SXT are
  reviewed together with a design study of two different hyperboloid
  lengths. An objective grating for studying point-source spectra is
  examined, and several focal-plane detectors are discussed, including
  an image-sensitive proportional counter, a channel electron multiplier
  array, and a gas scintillation proportional counter. SXT sensitivity
  is estimated for eight wavelength ranges between 8 and 1100 A.

---------------------------------------------------------
Title: Solar X-ray spectroscopy with a Bent Crystal Spectrometer /BCS/
Authors: Rapley, C. G.; Culhane, J. L.; Acton, L. W.; Catura, R. C.;
   Joki, E. C.; Bakke, J. C.
1977cosp.meetR....R    Altcode:
  A high-resolution Bent Crystal Spectrometer (BCS) which provides
  simultaneous and continuous time coverage of a range of wavelengths is
  described; its application to spectral studies of solar X-ray emission
  is discussed. Design of the BCS and its accompanying position-sensitive
  detector is considered. Calibrations of the crystal curvature, the
  angle between a crystal reference plane and the collimator axis, and
  the position response of the position-sensitive proportional counter
  in determining absolute wavelengths are also mentioned. An active
  solar region spectrum obtained during an airborne BCS test is compared
  to wavelength data derived from theory or previous experiments, and
  excellent agreement is found. Specifications for a BCS system to be
  used in the Solar Maximum Mission satellite of 1979 are given.

---------------------------------------------------------
Title: The X-ray spectrum and structure of the supernova remnant
    IC 443.
Authors: Parkes, G. E.; Charles, P. A.; Culhane, J. L.; Ives, J. C.
1977MNRAS.179...55P    Altcode:
  Ariel V observations of IC 443 in the energy range from 1.1 to 7.5
  keV are presented. The data permit the spectral parameters of this
  source to be more tightly constrained than in previous observations
  and provide information on the location of the emitting regions. No
  evidence for iron line emission at 6.7 keV is found. A source model
  is presented in which the initial explosion expands into a density
  gradient in the northeastern direction. This model consistently
  explains the observational properties of the remnant and predicts an
  age of 12,700 yr.

---------------------------------------------------------
Title: Detection of O VIII line emission in the X-ray spectrum of
    Puppis A.
Authors: Zarnecki, J. C.; Culhane, J. L.
1977MNRAS.178P..57Z    Altcode:
  Summary. The detection of the 0 VIII resonance line at 18.97 A in the
  X-ray spectrum of Puppis A is reported. The observation was carried
  out by means of a Bragg crystal spectrometer flown on a sounding
  rocket. Further evidence is obtained for the existence of material at
  two temperatures in the source. An upper liinit is placed on the gas
  column density to the source.

---------------------------------------------------------
Title: Detection of iron line emission in the Ariel V X-ray spectrum
    of the Centaurus cluster of galaxies.
Authors: Mitchell, R. J.; Culhane, J. L.
1977MNRAS.178P..75M    Altcode:
  Summary. Observations of the Centaurus cluster with the MSSL
  proportionalcounter spectrometer on the Ariel V satellite reveal the
  presence of a 7-keV feature which is identified with emission from Fe
  xxv and Fe xxvi ions.

---------------------------------------------------------
Title: The X-ray structure of supernova remnants - I. Cassiopeia A.
Authors: Charles, P. A.; Culhane, J. L.; Fabian, A. C.
1977MNRAS.178..307C    Altcode:
  Copernicus observations of the supernova remnant Cas A have been
  reanalyzed using an algebraic reconstruction technique (ART) to
  investigate further the X-ray structure of the source on a scale of
  3 arcmin. This structure contains certain features similar to those
  observed at radio wavelengths with a comparable beam size. Additional
  X-ray observations through a 1.7-arcmin aperture confirm the main
  features of the ART X-ray map. The reliability and accuracy of
  the reconstruction technique are examined in detail. The spatial
  inhomogeneity and high X-ray luminosity of Cas A may be due to the
  blast wave interacting with matter ejected prior to the supernova
  explosion. Alternatively, a 'reverse' shock may be heating material
  ejected in the supernova itself.

---------------------------------------------------------
Title: Extended soft X-ray emission from the Crab nebula.
Authors: Charles, P. A.; Culhane, J. L.
1977ApJ...211L..23C    Altcode:
  The grazing-incidence X-ray telescopes on the Copernicus satellite were
  used to scan the Crab Nebula with an angular resolution of approximately
  2 arcmin. Using a more precise technique for removing the non-X-ray
  background, the 0.5-1.5-keV data from this scan are processed with
  the ART algorithm. A significant extension to the northeast of the
  nebula is found which is also evident in the raw data. A more diffuse
  emission region is also apparent to the south of the nebula. These
  features may be associated with the residual soft X-ray flux observed
  during a lunar occultation of the Crab Nebula. The present data are
  consistent with the extensions having a spectrum which is softer than
  that of the main X-ray source in the Crab Nebula.

---------------------------------------------------------
Title: X-rays from clusters of galaxies.
Authors: Culhane, J. L.
1977cgci.conf..293C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: X-Rays from Supernova Remnants
Authors: Culhane, J. L.
1977ASSL...66...29C    Altcode: 1977supe.conf...29C
  No abstract at ADS

---------------------------------------------------------
Title: Cosmic X-Ray Spectroscopy.
Authors: Culhane, J. L.
1977uxsa.collE...3C    Altcode: 1977IAUCo..43.....C
  No abstract at ADS

---------------------------------------------------------
Title: A study of four X-ray sources with properties similar to
    Sco X-1.
Authors: Mason, K. O.; Charles, P. A.; White, N. E.; Culhane, J. L.;
   Sanford, P. W.; Strong, K. T.
1976MNRAS.177..513M    Altcode:
  Copernicus and Ariel V observations are reported for four X-ray
  sources which exhibit a correlation of intensity and spectral slope
  on timescales similar to that seen in Sco X-1. These sources include
  3U 0614+09, 3U 1702-36 (Sco X-2), 3U 1728-16 (GX 9+9), and 3U 1758-25
  (GX 5-1). The mean spectral parameters of each source are given, the
  short- and long-term behavior of different sources are described, and
  it is suggested that the similar X-ray characteristics of these four
  sources and Sco X-1 might indicate some degree of physical similarity
  as well as a similar optical and radio appearance. The observations are
  shown to strengthen the case for identifying 3U 0614+09 and 3U 1728-16
  with relatively faint blue stars in or near their X-ray error boxes.

---------------------------------------------------------
Title: Detection of an extreme-ultraviolet source in the southern sky.
Authors: Henry, P.; Bowyer, S.; Rapley, C. G.; Culhane, J. L.
1976ApJ...209L..29H    Altcode:
  The 3700 square degrees around the South Equatorial Pole have
  been surveyed using a broad-band photometer with peak response at
  90 A. One source was detected at about the same intensity as HZ
  43. An extrapolation of the results implies that there are about 10
  extreme-ultraviolet objects over the whole sky which are as bright
  as HZ 43. Implications of these results for theories of white dwarf
  evolution are briefly discussed.

---------------------------------------------------------
Title: The Relation Between Temperature and X-ray Luminosity for
    Clusters of Galaxies.
Authors: Mitchell, R. J.; Ives, J. C.; Culhane, J. L.
1976BAAS....8..553M    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The X-ray Temperature of Puppis A.
Authors: Charles, P. A.; Culhane, J. L.; Zarnecki, J. C.; Seward,
   F. D.; Toor, A.
1976BAAS....8..529C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: A European X-Ray Spectroscopy and Polarimetry Payload for
    Spacelab
Authors: Andresen, R. D.; Brinkman, A. C.; Beuermann, K.; Culhane,
   J. L.; Griffiths, R.; Manno, V.; Rocchia, R.; Whitcomb, G.
1976SSI.....2..325A    Altcode:
  A group of instruments for X-ray spectroscopy and polarimetry studies
  of a number of cosmic X-ray sources is being designed for possible
  use on Spacelab. Large area Bragg spectrometers and polarimeters for
  photon energies above 2 keV are described. For the energy range below 2
  keV, both dispersive and non-dispersive spectrometers are employed at
  the common focus of a nested array of paraboloids. Following a brief
  outline of the scientific background to the mission, the properties
  of the individual instruments are discussed.

---------------------------------------------------------
Title: Proceedings of the symposium on the techniques of solar and
    cosmic X-ray spectroscopy. Held at Holmbury, England, 22 and 23
    May 1975.
Authors: Acton, L. W.; Culhane, J. L.
1976SSI.....2....1A    Altcode: 1976STIA...7647776A
  Papers are presented on the spectroscopic analysis of solar and cosmic
  X-ray spectra, the absolute calibration of the reflection integral
  of Bragg X-ray analyzer crystals, the design and construction of
  modulation collimators, and Si(Li) X-ray astronomy aboard the HEAO-B
  satellite. Attention is also given to the OSO 8 instrument for stellar
  and solar X-ray spectroscopy and polarimetry, a soft X-ray spectrometer
  for diffuse sources, instrumentation for solar spectrophotometry at
  extreme ultraviolet and soft X-ray wavelengths, the calibration of
  the Ariel 5 Bragg spectrometer and a European X-ray spectroscopy and
  polarimetry payload for Spacelab. Individual items are announced in
  this issue.

---------------------------------------------------------
Title: A New Type of Crystal Spectrometer for Cosmic X-Ray Studies
Authors: Berthelsdorf, R. F.; Mitchell, R. J.; Culhane, J. L.
1976SSI.....2..349B    Altcode:
  A crystal spectrometer using a crystal panel curved in two dimensions
  and a position sensitive proportional counter is described. The
  instrument uses conical focussing to minimize detector size, and the
  crystal panel is bent to simultaneously present a range of Bragg angles
  to incoming X-rays, resulting in a one-to-one correspondence between
  the energy of a reflected X-ray and its point of incidence on the
  proportional counter. The advantages of such an instrument are high
  sensitivity, mechanical simplicity, and the capability of measuring
  spectra of rapidly varying sources.

---------------------------------------------------------
Title: The X-ray structure of the Perseus cluster of galaxies.
Authors: Wolff, R. S.; Mitchell, R. J.; Charles, P. A.; Culhane, J. L.
1976ApJ...208....1W    Altcode:
  The X-ray source in the Perseus cluster has been studied both by
  the Copernicus satellite and by sounding-rocket instruments flown
  by Columbia University. The spatial and spectral data from these
  observations are examined. A surface brightness distribution is obtained
  which shows that the source consists of a compact core associated
  with NGC 1275 and a more extended emission volume. The structure
  of the central core region has been examined by means of an image
  reconstruction technique, revealing a steeply declining luminosity
  function and north-south elongation. The spectrum of the emission of
  the core region is distinguished from that of the surrounding area
  and found to be consistent with a hydrogen column density of 2.5 x 10
  to the 21th/sq cm. A comparison between the isothermal and adiabatic
  gas sphere models is presented which shows the need for at least two
  components to provide the X-ray emission.

---------------------------------------------------------
Title: Some implications of the X-ray data from old supernova
    remnants.
Authors: Clark, D. H.; Culhane, J. L.
1976MNRAS.175..573C    Altcode:
  Several old supernova remnants emit soft X-rays. With certain
  assumptions, and using a standard adiabatic shock-wave model, values
  for the initial blast energy of a supernova and the age of its remnants
  may be estimated. These parameters are evaluated using the most recently
  available X-ray and radio results for four old supernova remnants. The
  data imply high ratios of initial blast energy to interstellar density
  and comparatively young ages for the remnants. These conclusions,
  while at variance with some earlier estimates based on optical and
  radio data, support the results of a statistical analysis of the most
  recent catalog of radio remnants. Predicted X-ray fluxes for other
  supernova remnants lying within 6 kpc of the sun are presented as a
  guide to future observational programs.

---------------------------------------------------------
Title: Detection of an Extreme Ultraviolet Source in the Southern
    Hemisphere
Authors: Henry, P.; Bowyer, S.; Rapley, C. G.; Culhane, J. L.
1976BAAS....8S.447H    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The Spectra and Structure of Extra Galactic X-ray Sources
Authors: Culhane, J. L.
1976BAAS....8R.445C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Observations of the Low Energy Diffuse X-ray Background
Authors: Rapley, C. G.; Bell-Burnell, S. J.; Culhane, J. L.
1976BAAS....8..446R    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: `Copernicus' observations of extragalactic X-ray sources
Authors: Fabian, A. C.; Mitchell, R. J.; Davison, P. J. N.; Charles,
   P. A.; Culhane, J. L.
1976Ap&SS..42..249F    Altcode:
  The MSSL X-ray detectors onCopernicus have been used to study a
  number of extragalactic objects. At least three classes of unresolved
  sources are found and we suggest that accretion may be the dominant
  mechanism. The mass of the accreting object then determines the X-ray
  emission properties.

---------------------------------------------------------
Title: X-Ray Spectra of Cas A and Tycho's Supernova observed with
    Ariel-5
Authors: Davison, P. J. N.; Culhane, J. L.; Mitchell, R. J.
1976BAAS....8..448D    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Periodic Modulation of the X-ray Flux from Four Galactic
    X-ray sources
Authors: White, N. E.; Huckle, H. E.; Mason, K. O.; Charles, P. A.;
   Pollard, G.; Culhane, J. L.; Sanford, P. W.
1976BAAS....8Q.441W    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Four Sources which show X-ray Behaviour similar to Sco X-1
Authors: Mason, K. O.; Charles, P. A.; White, N. E.; Culhane, J. L.;
   Sanford, P. W.; Strong, K. T.
1976BAAS....8..443M    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: X-ray spectra of Cassiopeia A and Tycho's supernova observed
    with Ariel-5.
Authors: Davison, P. J. N.; Culhane, J. L.; Mitchell, R. J.
1976ApJ...206L..37D    Altcode:
  The proportional counter on Ariel-5 has observed the X-ray spectra
  of Cas A and Tycho's supernova from 1.5 to 18 keV and 13 keV,
  respectively. Both spectra are well fitted by two-component thermal
  models. The higher-temperature component can in each case account
  for an emission feature due to Fe XXV, which is observed at about 6.7
  keV. Estimates of the iron abundance for each source are presented on
  the basis of these models.

---------------------------------------------------------
Title: Ariel 5 observations of the X-ray spectrum of the Perseus
    cluster.
Authors: Mitchell, R. J.; Culhane, J. L.; Davison, P. J. N.; Ives,
   J. C.
1976MNRAS.175P..29M    Altcode:
  An X-ray spectrum of the Perseus Cluster in the energy range 1.3-16
  keV has been obtained with the MSSL collimated proportional counter
  on Ariel 5. An emission feature has been detected at about 7 keV of
  strength about 0.0035 photon per sq cm per sec. The existence of this
  feature, which is due to Fe XXV and Fe XXVI transitions, provides strong
  evidence for the presence of hot plasma in the cluster. In addition the
  overall spectrum is well described by the bremsstrahlung emitted from
  an adiabatic hydrostatic atmosphere of hot gas in the gravitational
  potential well of the cluster.

---------------------------------------------------------
Title: X-ray observations of NGC 5128.
Authors: Stark, J. P.; Davison, P. J. N.; Culhane, J. L.
1976MNRAS.174P..35S    Altcode:
  Observations of the active galaxy NGC 5128 (Centaurus A) have been made
  by the satellite Ariel V for a two-day period in 1975 January, and by
  the satellite Copernicus for one day in 1975 July. The observations from
  Ariel V permit an accurate description of the X-ray spectrum to be made
  over the band 1.3-28.7 keV. The best-fit spectrum is a power law with
  photon index of -1.79 + or - 0.02 for a line-of-sight hydrogen column
  density of 1.35 + or - 0.02 times 10 to the 23rd atom per sq cm. The
  absence of an iron absorption feature in the spectrum allows us to set
  an upper limit of twice the normal cosmic value to the abundance of
  iron. The flux detected in January was higher than had been previously
  observed, but by July this flux level had fallen by 40 per cent.

---------------------------------------------------------
Title: The X-ray variability of Vela X-1 (3U 0900-40).
Authors: Charles, P. A.; Mason, K. O.; Culhane, J. L.; Sanford, P. W.;
   White, N. E.
1976NASSP.389..629C    Altcode: 1976NASSP.589..629C; 1976xrbi.nasa..629C
  From observations of Vela X-1 with the MSSL 2.5-7.5 keV detector
  onboard Copernicus, the behavior of the source can be characterized
  by three phases: (1) high intensity, (2) low intensity, and (3)
  eclipse. Combining data from the 1972 Uhuru observations with eclipse
  observation yields a binary period of 8.963 + or - 0.001 days with
  zero phase on 1975 Feb. 6.97 + or - 0.04 UT. The low intensity phase
  is interpreted as being due to increased absorption in an accretion
  wake traveling across the line of sight (the spectral slope remains
  relatively constant throughout the cycle). Another period of enhanced
  absorption immediately after exit from eclipse may be due to a
  bow shock. Comparison of the two observations suggests that these
  structures vary from cycle to cycle and, since the orbital period is
  long, probably during each cycle.

---------------------------------------------------------
Title: Copernicus observations of a number of galactic X-ray sources.
Authors: Culhane, J. L.; Mason, K. O.; Sanford, P. W.; White, N. E.
1976NASSP.389....1C    Altcode: 1976NASSP.589....1C; 1976xrbi.nasa....1C
  The Copernicus satellite was launched on 21 August 1972. The main
  experiment on board is the University of Princeton UV telescope. In
  addition a cosmic X-ray package of somewhat modest aperture was provided
  by the Mullard Space Science Laboratory (MSSL) of University College
  London. Following a brief description of the instrument, a list of
  galactic sources observed during the year is presented. Although the
  X-ray detection aperture is small, the ability to point the satellite
  for long periods of time with high accuracy makes Copernicus an ideal
  vehicle for the study of variable sources.

---------------------------------------------------------
Title: Techniques of Solar and Cosmic X-ray Spectroscopy
Authors: Acton, L. W.; Culhane, J. L.
1976SSI.....2.....A    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Observations of the soft X-ray diffuse background.
Authors: Rapley, C. G.; Burnell, S. J. B.; Culhane, J. L.
1976spre.conf..839R    Altcode: 1976spre.proc..839R
  Observations of the soft X-ray diffuse background using a large
  area, low-energy proportional counter aboard a Skylark rocket are
  reported. Data have been obtained from a strip of sky extending from
  the galactic plane to the North Galactic Pole. At least two regions of
  enhanced emission and one absorption feature have been detected. We
  discuss the association of these features with the radio loops and
  two neutral hydrogen ridges. We show that there is strong evidence
  for the existence of soft X-ray emission from beyond the bulk of the
  galactic absorbing gas. It is likely that this emission is associated
  with relatively local structures extending out of the galactic disc
  rather than a galactic halo.

---------------------------------------------------------
Title: X rays from supernova remnants.
Authors: Charles, P. A.; Culhane, J. L.
1975SciAm.233f..38C    Altcode: 1975SciAm.233...38C
  Analysis of X-ray emission from supernova remnants is aided by
  grazing-incidence X-ray cameras borne by satellites and by utilizing
  lunar occultation. The analysis provides new data on supernova ejecta
  and the structure of the surrounding interstellar medium as the shocked
  material ejected by the exploded supernova interacts with dust-gas
  clouds. The presence in the Crab Nebula of a pulsar responsible for
  enormous energy emission at visible, radio, and X-ray wavelengths is
  confirmed, but the X-ray emission mechanism at work in Cassiopeia A and
  in Tycho's nova appears to be complex interaction between high-velocity
  magnetohydrodynamic shock waves and interstellar material swept up by
  the shocks.

---------------------------------------------------------
Title: Soft X-ray search of centre of Cygnus Loop
Authors: Snyder, W. A.; Henry, R. C.; Charles, P. A.; Culhane, J. L.;
   Sanford, P. W.; Bleach, R.; Drake, J.
1975Natur.258..214S    Altcode:
  Equipment on the Copernicus satellite has been used to search for
  evidence of a compact object in the center of the Cygnus Loop supernova
  remnant. Rocket measurements reported by Rappaport et al. (1973)
  indicate that a central object exists. However, the study conducted
  with the aid of the satellite was negative. This negative result could
  indicate that the X-ray source was simply not in its high-intensity
  mode at the time of observation, or could arise because the source is
  at some other location in the Loop.

---------------------------------------------------------
Title: X-Ray Sources
Authors: White, N. E.; Huckle, H. E.; Mason, K. O.; Charles, P. A.;
   Pollard, G.; Culhane, J. L.; Sanford, P. W.
1975IAUC.2870....1W    Altcode:
  N. E. White, H. E. Huckle, K. O. Mason, P. A. Charles, G. Pollard,
  J. L. Culhane and P. W. Sanford, Mullard Space Science Laboratory,
  write: "The Copernicus and Ariel 5 (experiment C) satellites have
  made observations of seven galactic x-ray sources in the energy range
  3-8 keV. The results of a search for modulation of the x-ray flux in
  the period range 2.5-50 min are as follows: Source Satellite Date C
  Period (min) A 3U 1223-62 Ariel 1975 Jan. 5 39 11.64 +/- 0.02 50 3U
  1728-24 Copernicus 1972 Sept.11 47 4.315 +/- 0.004 12 3U 1728-24 "
  1973 Mar. 25 31 4.39 +/- 0.07 20 3U 1813-14 " 1975 Aug. 1 254 31.9 +/-
  0.1 4 C gives the mean count per min. The amplitude A (percent) quoted
  is the peak to mean amplitude as a percentage of the mean flux. Four
  sources, 3U 1702-36, 1728-16, 1757-25 and 1811-17, showed no detectable
  modulation with upper limits to the amplitude, of 15, 5, 4 and 4
  percent, respectively, when observed with Copernicus. The 4.3-min
  period of 3U 1728-24 is close to twice the 2.3-min period suggested
  by Lewin et al. (1971, Astrophys. J. 169, L17) from higher energy data."

---------------------------------------------------------
Title: Copernicus: X-ray observations of several radio supernova
    remnants.
Authors: Zarnecki, J. C.; Stark, J. P.; Charles, P. A.; Culhane, J. L.
1975MNRAS.173..103Z    Altcode:
  The MSSL X-ray detectors on Copernicus have observed five radio sources,
  3C 392, DR4, MSHI5-52A and Downes Nos 83 and 84 in the energy range -
  keV. The first three objects are thought to be supernova remnants. We
  present here upper limits from our observations and in the case of 3C
  392 a possible positive detection of X-ray emission. We also comment
  on the variability of the X-ray source 3U 1901 + 03.

---------------------------------------------------------
Title: Extended Soft X-Ray Emission from the Crab Nebula
Authors: Charles, P. A.; Culhane, J. L.
1975BAAS....7R.505C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: X-ray emission from the Centaurus cluster.
Authors: Mitchell, R. J.; Charles, P. A.; Culhane, J. L.; Davison,
   P. J. N.; Fabian, A. C.
1975ApJ...200L...5M    Altcode:
  X-ray emission from the Centaurus cluster of galaxies has been studied
  in the energy range 0.6-7.5 keV using the MSSL X-ray telescopes on
  the Copernicus satellite. Exponential and power-law spectra fit the
  data equally well. A value of the interstellar column density is
  found which is in good agreement with radio observations. The X-ray
  emission detected in the 12-minute field of view of the Copernicus
  telescope is much greater than would be expected on the basis of the
  Uhuru isothermal gas sphere model. This may indicate either that the
  size of the extended X-ray source is less than reported by Kellogg
  and Murray or that the galaxy NGC 4696 is a relatively compact source
  embedded in the general emission from the cluster.

---------------------------------------------------------
Title: Galactic X-ray sources
Authors: Culhane, J. L.
1975xrat.rept....3C    Altcode:
  Categories of galactic X-ray sources taken from the Uhuru catalog
  are discussed. The Uhuru sources are classified by galactic latitude
  into galactic and extra galactic populations. The galactic sources
  include a group of highly luminous objects near the galactic center,
  the compact X-ray sources in binary systems, and the X-ray emitting
  supernova remnants. Galactic center sources are briefly dicussed and
  compact object binary sources are examined in detail. The supernova
  remnants are considered, and brief remarks are made about sources in
  globular clusters and transient X-ray sources.

---------------------------------------------------------
Title: Copernicus: the X-ray spectrum of Cassiopeia A.
Authors: Charles, P. A.; Culhane, J. L.; Zarnecki, J. C.; Fabian, A. C.
1975ApJ...197L..61C    Altcode:
  The MSSL X-ray telescopes on Copernicus have obtained the spectrum
  of the supernova remnant Cas A in the energy range 0.5-7.5 keV. The
  observations may be explained by a two-component thermal spectrum
  with temperatures of 8 and 30 million degrees K. This result can be
  broadly interpreted in terms of McKee's (1974) reverse-shock-wave
  model of young remnants where the lower temperature is attributed
  to the reverse shock and the higher one to the initial blast wave. A
  3-sigma upper limit of 0.02 photons per sq cm per sec was also derived
  for the emission from a line feature at 2 keV.

---------------------------------------------------------
Title: Recent Copernicus Results on the X-ray Emission from Supernova
    Remnants.
Authors: Charles, P. A.; Culhane, J. L.; Rapley, C. G.; Zarnecki,
   J. C.; Fabian, A. C.
1975BAAS....7Q.246C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Copernicus: The Spatial Distribution of the X-ray Emission
    from IC443
Authors: Charles, P. A.; Culhane, J. L.; Rapley, C. G.
1975ApL....16..129C    Altcode:
  The MSSL X-ray instrumentation on the Copernicus satellite has observed
  the spatial structure of the supernova remnant IC 443. The soft (0.5-1.4
  keV) X-ray emission is found to be strongly correlated with the bright
  optical filaments in the northeast. The total intensity is consistent
  with previous observations of the remnant. An upper limit of 4 by 10
  to the -11th power erg/sq cm/sec can also be assigned to the flux in
  the 0.5-1.4-keV band from the nearby pulsar PSR 0611 + 22.

---------------------------------------------------------
Title: An increase in the X-ray flux from Centaurus A.
Authors: Davison, P. J. N.; Culhane, J. L.; Mitchell, R. J.; Fabian,
   A. C.
1975ApJ...196L..23D    Altcode:
  Observations of the 0.5-7.5 keV X-ray spectrum of Centaurus A (Cen A)
  were made by the Copernicus satellite in June, 1973. The luminosity
  of the source in the 2.5-7.5 keV range is found to have increased by
  a factor of 4 in the two years since the last reported observation by
  the Uhuru satellite. The value of the absorbing gas column density and
  the power law index are consistent with those determined by Uhuru. The
  luminosity increase indicates that the emitting region responsible
  for it is only a few light years in extent, confirming that the X-ray
  source is the nucleus of Cen A.

---------------------------------------------------------
Title: Measured offset between the Crab pulsar and Tau X-1
Authors: Davison, P. J. N.; Culhane, J. L.
1975Natur.253..610D    Altcode:
  WE have used the MSSL X-ray detector on board the Copernicus spacecraft
  to measure the effective diameter of the Crab Nebula and to measure the
  location of the centroid of the emission with respect to the accurately
  known pulsar position<SUP>1</SUP>.

---------------------------------------------------------
Title: Copernicus: soft X-ray emission from certain features of the
    Cygnus Loop.
Authors: Charles, P. A.; Culhane, J. L.; Zarnecki, J. C.
1975ApJ...196L..19C    Altcode:
  Observations made with the MSSL 0.5-1.5 keV X-ray telescope on board
  Copernicus of several features of previous X-ray maps of the Cygnus
  Loop, including the prominent filaments (NGC 6992-5) in the northeastern
  part and a region in the northern part containing some scattered
  filaments and a small peak in the radio emission, are discussed. A
  thermal continuous spectrum is used to fit the satellite data to the
  X-ray maps, and emission fluxes and spectra are calculated for the
  filamentary regions. The results tend to confirm the existence of the
  previously mapped bright X-ray emitting regions, and support Stevens'
  interpretation that an encounter between the initial blast wave from
  the supernova and an inhomogeneous interstellar medium has caused the
  discrepancy between the observed optical filament velocities and the
  implied shock velocities necessary for the observed X-ray emission.

---------------------------------------------------------
Title: Spatially Resolved X-Ray Spectra of Coronal Active Regions
Authors: Catura, R. C.; Acton, L. W.; Joki, E. G.; Rapley, C. G.;
   Culhane, J. L.
1975IAUS...68...67C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: X-ray astronomy with Copernicus.
Authors: Parkinson, J. H.; Culhane, J. L.; Hawkins, F. J.; Sanford,
   P. W.
1975spre.conf..663P    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Upper Limits for X-Ray Emission from Jupiter as Measured from
    the Copernicus Satellite
Authors: Vesecky, J. F.; Culhane, J. L.; Hawkins, F. J.
1975ASSL...52..245V    Altcode: 1975msej.symp..245V
  X-ray telescopic observations are made by the Copernicus satellite
  for detecting X-ray emission from Jupiter analogous to X-rays from
  terrestrial aurorae. Values of X-ray fluxes recorded by three Copernicus
  detectors covering the 0.6 to 7.5 keV energy range are reported. The
  detectors employed are described and the times at which the observations
  were made are given. Resulting upper-limit spectra are compared with
  previous X-ray observations of Jupiter. The upper-limit X-ray fluxes
  are discussed in terms of magnetospheric activity on Jupiter.

---------------------------------------------------------
Title: X-ray astronomy
Authors: Culhane, J. L.
1975VA.....19....1C    Altcode:
  The paper reviews the theory and practice of X-ray astronomy. Thermal
  and nonthermal mechanisms which produce X-rays in the energy range from
  0.1 to 20 keV are discussed, and X-ray absorption in the interstellar
  medium is examined along with X-ray scattering by interstellar
  grains. Instruments for X-ray astronomy are described, including gas
  proportional counters, scintillation counters, solid-state detectors,
  detectors with spatial resolution, various types of collimators,
  X-ray telescopes, spectrometers, and polarimeters. The development
  of solar X-ray studies is outlined, emphasizing X-ray emission from
  coronal structures, from coronal active regions, and from solar
  flares. Observations of extrasolar X-ray sources are discussed,
  concentrating on their distribution and on descriptions of many X-ray
  binaries, supernova remnants, and extragalactic sources. The diffuse
  X-ray background is examined, and possible sources are considered for
  the soft component of the diffuse flux.

---------------------------------------------------------
Title: Copernicus: The X-ray structure of the Crab Nebula
Authors: Hawkins, F. J.; Mason, K. O.; Sanford, P. W.; Culhane, J. L.
1974MNRAS.169P..41H    Altcode:
  The extent of the X-ray emitting region in the Crab Nebula is derived
  in two energy bands from observations by the Copernicus satellite. The
  measurements are compared with previous results and discussed in terms
  of a model for the nebular radiation.

---------------------------------------------------------
Title: Studies of the X-Ray Emission from Supernova Remnants
Authors: Culhane, J. L.
1974RSPSA.340..423C    Altcode:
  Supernova remnants are now recognized as a class of soft X-ray
  emitting-objects. The evolution of a remnant's X-ray emission is
  discussed and a number of possible X-ray emission mechanisms are
  described. The spectrum of the Crab Nebula has been studied with
  Copernicus. The data have been used to derive a value of the gas
  column density of the interstellar medium. The X-ray structure and
  spectrum of the remnant Cassiopeia A have been investigated and the
  results are presented. A high resolution X-ray map of the Puppis
  A supernova remnant has been obtained and the interpretation of the
  X-ray structure is discussed. X-ray emission has been detected from the
  pulsar PSR 08 33-45. This observation is compared with data obtained
  from the Uhuru satellite in order to derive the gas column density to
  the source. Weak soft X-ray emission has been detected from the Cygnus
  Loop in the regions expected but at a lower intensity - a search for
  regions of higher intensity is continuing. A programme to identify
  known radio remnants as X-ray emitters is in progress and the results
  obtained so far are reported.

---------------------------------------------------------
Title: A new type of crystal spectrometer for solar X-ray studies
Authors: Catura, R. C.; Joki, E. G.; Bakke, J. C.; Rapley, C. G.;
   Culhane, J. L.
1974MNRAS.168..217C    Altcode:
  A new type of crystal spectrometer for the study of the solar X-ray
  spectrum is described. Previous solar X-ray crystal spectrometers have
  required a scanning mechanism to move both the crystal and the detector
  so that the required range of wavelengths may be covered. By employing
  a crystal bent in the plane of dispersion, a range of wavelengths may
  be studied simultaneously by registering the dispersed spectrum with
  a position sensitive X-ray detector. Details of the instrument are
  presented together with some solar X-ray data obtained in an early
  flight of the device.

---------------------------------------------------------
Title: Some recent results in X-ray Astronomy
Authors: Culhane, J. L.
1974MmSAI..45..831C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Detection of Soft X-Ray Emission from PSR 0833-45
Authors: Culhane, J. L.; Cruise, A. M.; Rapley, C. G.; Hawkins, F. J.
1974ApJ...190L...9C    Altcode:
  An observation of the Vela pulsar in the energy range 0.7-1.5
  keV is presented. A comparison of the flux in this band with the
  spectrum of the source 3U 0833-45 for the 2-10 keV band suggests
  a low-energy turnover in the spectrum. The measurement is compared
  with other observations, and possible explanations of the turnover
  are discussed. Subject headings: pulsars - X-ray sources

---------------------------------------------------------
Title: Copernicus: spectral studies of Cas-A and Pup-A
Authors: Charles, P. A.; Culhane, J. L.; Zarnecki, J. C.; Fabian, A. C.
1974MmSAI..45..699C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Copernicus X-Ray Observations of NGC 1275 and the Core of
    the Perseus Cluster
Authors: Fabian, A. C.; Zarneck, J. C.; Culhane, J. L.; Hawkins,
   F. J.; Peacock, A.; Pounds, K. A.; Parkinson, J. H.
1974ApJ...189L..59F    Altcode:
  The Perseus cluster of galaxies has been studied with 0.5-1.5 keV and
  1. .1 keV grazing-incidence X-ray telescope systems on the Orbiting
  Astronomical Observatory, Copernicus. Observations with a range of
  apertures (12', 6', and 2') defining the field of view reveal the
  presence of a compact X-ray source centered 35ff + 30" north of NGC
  1275. This has less than 3' extent, and we identify the X-ray source
  with NGC 1275. The core of the extended cluster emission observed
  with Uhurn is also detected. If it is assumed that the cluster core
  X-ray emission distribution is independent of energy, then the X-ray
  intensity of NGC 1275 is percent of the total cluster emission, and
  may have a similar spectrum. We therefore deduce a 0.5-1.5 keV X-ray
  luminosity of either 1 X 10 or 2.5 X 10 ergs 1 (H0 = 50 km s ' ) for
  NGC 1275. We discuss the isothermal gas sphere model for the cluster
  core, provide upper limits in the 0.5-1.5 keV range for NGC 1265 and
  IC 310 which are within the cluster, and consider the compatibility
  of our results with other published data. Subject headings: galaxies,
  clusters of - X-ray sources

---------------------------------------------------------
Title: Upper limit to the flux of soft X rays from λ-Sco
Authors: Strong, K. T.; Colley, M. W.; Culhane, J. L.
1974Natur.248...34S    Altcode:
  DURING a rocket flight on May 26, 1971 which carried a number of
  large area thin window proportional counters, a soft X-ray source
  was observed by Bleeker et al.<SUP>1</SUP> in Scorpio. Photons in the
  energy range 0.37 keV to 1.9 keV were detected from a position error
  box of approximately 40 square degrees. This admittedly large error box
  contains the bright star λ-Sco and it was suggested that this object
  may be the source of the soft X-ray emission that was detected. It
  is a B1 V star and exhibits a varying radial velocity with a period
  of about 5.6 d. It has a visual magnitude of 1.62 and its distance is
  estimated as 100 pc (ref. 2).

---------------------------------------------------------
Title: Low Energy X-ray Observations of PSR 0833-45
Authors: Cruise, A. M.; Culhane, J. L.; Rapley, C. G.; Hawkins, F.
1974BAAS....6..271C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Soft X-ray observations of supernova remnants.
Authors: Zarnecki, J. C.; Culhane, J. L.; Fabian, A. C.; Rapley,
   C. G.; Boyd, R. L. F.; Parkinson, J. H.; Silk, R.
1974olns.conf..565Z    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Soft X-ray observations of supernova remnants
Authors: Zarnecki, J. C.; Culhane, J. L.; Fabian, A. C.; Rapley,
   C. G.; Boyd, R. L. F.; Parkinson, J. H.; Silk, R.
1974HiA.....3..565Z    Altcode:
  Observations of a number of supernova remnants have been carried out
  with the low energy X-ray telescope on the Copernicus satellite. Data
  are presented on the X-ray structure of the remnants Cassiopeia A and
  Puppis-A. Marginal detections or new upper limits are reported for
  the remnants IC443, DR4, MSH15-52A, Downes 83, Downes 84, and 3C392.

---------------------------------------------------------
Title: The solar X-ray spectrum.
Authors: Culhane, J. L.; Acton, L. W.
1974ARA&A..12..359C    Altcode:
  The characteristics of X-ray emission from the normal corona are
  considered, giving attention to questions of spatial and spectral
  distribution. Aspects of X-ray emission from solar flares are
  also investigated. Details of X-ray spectroscopy for coronal plasma
  diagnosis are discussed, taking into account techniques, the diagnosis
  of equilibrium plasmas, and the diagnosis of nonthermal events. The
  study of continuum emission and line emission is reported along with
  investigations of departures from equilibrium.

---------------------------------------------------------
Title: Low Energy X-ray Map of Puppis A Supernova Remnant
Authors: Zarnecki, J. C.; Culhane, J. L.; Fabian, A. C.; Rapley,
   C. G.; Silk, R.; Parkinson, J. H.; Pounds, K. A.
1973NPhS..243....4Z    Altcode: 1973Natur.243....4Z
  THE low energy X-ray emission from the Puppis A supernova remnant
  has recently been observed with the Mullard Space Science Laboratory
  grazing incidence telescopes on Copernicus. The instrumentation has
  been described before<SUP>1</SUP>. The observations reported here are
  from the 0.5-1.5 keV detector system. The whole of the radio remnant
  has been mapped using the 10 arc min field of view. Some additional
  data from the 6 arc min field of view are also presented.

---------------------------------------------------------
Title: The Soft X-Ray Structure of Cassiopeia A
Authors: Fabian, A. C.; Zarnecki, J. C.; Culhane, J. L.
1973NPhS..242...18F    Altcode: 1973Natur.242...18F
  The supernova remnant Cas A is identified as an extended source of
  soft X-rays. No evidence is found for the presence of a compact X-ray
  source. There are indications of non-uniformity in the X-ray surface
  brightness.

---------------------------------------------------------
Title: Further Results on Cooling Mechanisms for Soft X-ray Flares
Authors: Craig, I. J. D.; Culhane, J. L.; Phillips, K. J. H.; Vesecky,
   J. F.
1973NASSP.342..276C    Altcode: 1973heps.conf..276C
  No abstract at ADS

---------------------------------------------------------
Title: X-ray study of solar plage regions and a small flare.
Authors: Acton, L. W.; Catura, R. C.; Culhane, J. L.
1973spre.conf..781A    Altcode: 1973spre....2..781A
  No abstract at ADS

---------------------------------------------------------
Title: Interstellar absorption of the lowenergy X-rays from the
    Crab Nebula
Authors: Charles, P. A.; Culhane, J. L.; Tuohy, I. R.
1973MNRAS.165..355C    Altcode:
  Observations of the soft X-ray emission from the Crab Nebula, made
  with the MSSL X-ray telescopes on board the satellite Copernicus,
  require a review of the currently accepted interstellar abundances
  of light elements. The soft X-ray data imply a gas column density of
  ( i o ) x 1021 atoms cm-2 using Brown &amp; Gould X-ray absorption
  cross-sections. Results obtained from 21 cm radio measurements indicate
  a lower value of the column density. Better agreement between the
  X-ray and radio values can be obtained by increasing the abundances
  of helium and neon over those assumed by Brown &amp; Gould.

---------------------------------------------------------
Title: The sixteenth Herstmonceux conference, 1972 April 5 - 6. Cosmic
    X-ray sources.
Authors: Pounds, K. A.; Miley, G. K.; Murdin, P.; Webster, B. L.;
   Pacini, F.; Pringle, J. E.; Jackson, J. C.; Morrison, L. V.; Culhane,
   J. L.; Sciama, D. W.; Fabian, A. C.; Brown, J. C.; Gabriel, A. H.;
   Bingham, R. G.; Lategan, A. H.; Pagel, B. E. J.
1972Obs....92..193P    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Coronal survey in X-rays of O  vii and Ne  ix
Authors: Acton, L. W.; Catura, R. C.; Meyerott, A. J.; Wolfson, C. J.;
   Culhane, J. L.
1972SoPh...26..183A    Altcode:
  We report some results of a rocket experiment flown on 29 April,
  1971. A survey of the solar corona was carried out with a pair of
  collimated Bragg spectrometers to study the resonance, intersystem and
  forbidden line emission from the helium-like ions O VII (22 Å) and
  Ne IX (13 Å). In the direction of dispersion the collimator provided
  a field of view of 1.7'. Also, the continuum radiation near 3 Å was
  monitored by a collimated proportional counter within a view angle
  of 4.2'. The observed X-ray emission came from the general corona,
  seven plage regions, and one dynamic feature- the late stage of a small
  flare. From the intensity of the O VII and Ne IX resonance lines the
  electron temperature and emission measure of the individual emitting
  regions are derived on the basis of two models, one (a) in which the
  region is assumed to be isothermal and another (b) in which the emission
  measure decreases exponentially with increasing temperature. The
  latter model, which is the most adequate of the two, yields for the
  electron temperature of the time-varying feature 2-3 × 10<SUP>6</SUP>
  K, for the other active regions 1.5-2.5 × 10<SUP>6</SUP> K, and for
  the general corona 1.3-1.7 × 10<SUP>6</SUP> K. The Ne IX emitting
  regions are about 1.5 times as hot as the O VII regions. The emission
  measure ranges from 0.4-2.3 × 10<SUP>48</SUP> cm<SUP>−3</SUP> for
  all active regions and is about 2 × 10<SUP>49</SUP> cm<SUP>−3</SUP>
  for one hemisphere of the general corona above 10<SUP>6</SUP> K. From
  an analysis of the ratio, R, of the forbidden and intersystem lines
  of O VII we conclude that none of the regions producing these lines
  at the time of the rocket flight had electron densities exceeding
  about 3 × 10<SUP>9</SUP> cm<SUP>−3</SUP>. Our data demonstrate
  a dependence of R upon temperature in agreement with the theory of
  Blumenthal et al. (1971). The wavelengths for the intersystem, the
  1s<SUP>2</SUP>2s<SUP>2</SUP>S<SUP>e</SUP>−1s2p2s<SUP>2</SUP>P<SUP>0</SUP>
  satellite, and the forbidden transition show in the case of Ne IX
  improved agreement with predictions. The observed strength of the
  satellite lines for both O VII and Ne IX agrees with the predictions
  of Gabriel's (1972) theory, which attributes their formation to
  dielectronic recombination.

---------------------------------------------------------
Title: Mapping the Solar Corona in X-Ray Lines of O VII and NE IX
Authors: Catura, R. C.; Acton, L. W.; Meyerott, A. J.; Culhane, J. L.
1972SSRv...13..742C    Altcode: 1972IAUCo..14..742C
  No abstract at ADS

---------------------------------------------------------
Title: Analysis of X-Ray Line Emission from Individual Solar Active
    Regions
Authors: Catura, R. C.; Acton, L. W.; Wolfson, C. J.; Culhane, J. L.
1972BAAS....4R.379C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Origin of the Low Energy Diffuse Cosmic X-Ray Flux
Authors: Culhane, J. L.; Fabian, A. C.
1972Natur.237..379C    Altcode:
  While only the gross features of the low energy diffuse flux have been
  observed, it seems that a galactic component of diffuse soft X-rays is
  required. Forces of this flux should be distributed about the galactic
  plane with a scale height similar to that of the hydrogen.

---------------------------------------------------------
Title: Circuits for Pulse Rise Time Discrimination in Proportional
    Counters
Authors: Culhane, J. L.; Fabian, A. C.
1972ITNS...19..569C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The Cosmic X-Ray Experiments Selected for Oso-J
Authors: Culhane, J. L.
1972xanf.conf..105C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Helium-like Line Emission from Coronal Features
Authors: Acton, L. W.; Catura, R. C.; Meyerott, A. J.; Culhane, J. L.
1971NPhS..233...75A    Altcode: 1971Natur.233...75A
  SINCE Gabriel and Jordan<SUP>1</SUP> proposed the theory
  relating the relative intensity of the inter-system
  (<SUP>3</SUP>P-<SUP>1</SUP>S<SUB>0</SUB>) and forbidden
  (<SUP>3</SUP>S<SUB>1</SUB> - <SUP>1</SUP>S<SUB>0</SUB>) lines of
  helium-like ions to the electron density of the emitting volume there
  has been growing interest in using this type of information to determine
  electron densities in the solar corona<SUP>2-5</SUP>. We present here
  the preliminary results of a rocket experiment designed to study the
  OVII and NeIX line emission from discrete coronal features. These
  results indicate that electron densities in normal, non-flare, coronal
  features are below the low density limits (6 × 10<SUP>9</SUP> and 1
  × 10<SUP>11</SUP> cm<SUP>-3</SUP> respectively) given by Freeman et
  al.<SUP>5</SUP> for these particular ions.

---------------------------------------------------------
Title: A Comment on Solar Flare Iron Line Emission at 1.9 Å
Authors: Phillips, K. J. H.; Culhane, J. L.
1971SoPh...16..469P    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: A Rocket-Borne X-Ray Spectrometer Monochromator System for
    Mapping the Solar Corona
Authors: Action, L. W.; Catura, R. C.; Culhane, J. L.; Meyerott, A. J.
1971IAUS...41..181A    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Gradual rise and fall X-ray bursts aboard OSO-4.
Authors: Phillips, K. J. H.; Culhane, J. L.; Sanford, P. W.
1971spre.conf.1351P    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: The Cooling of Flare Produced Plasmas in the Solar Corona
Authors: Culhane, J. L.; Vesecky, J. F.; Phillips, K. J. H.
1970SoPh...15..394C    Altcode:
  Solar flare X-rays, at energies less than 10 keV, are emitted by
  hot plasmas located in the corona. Three plasma cooling models are
  examined in detail. The cooling of the electrons by Coulomb collisions
  with ions at a lower temperature would require the observed material
  to occupy very large volumes. Cooling could take place by conduction
  or by radiation and observations are proposed which would allow the
  dominant cooling mechanism to be established.

---------------------------------------------------------
Title: The Cooling of Flare-Produced Plasmas in the Solar Corona
Authors: Culhane, J. L.; Phillips, K. J. H.; Vesecky, J. F.
1970BAAS....2R.306C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Simultaneous Rocket and Satellite Observations of the Solar
    X-Ray Spectrum in the 3-15-keV Range
Authors: Culhane, J. L.; Acton, L. W.; Catura, R. C.
1970BAAS....2Q.307C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: X-Ray Line Emission from Scorpius X-1
Authors: Acton, L. W.; Catura, R. C.; Culhane, J. L.; Fisher, P. C.
1970ApJ...161L.175A    Altcode:
  Observations of the Sco X-1 source with a large-area proportional
  counter suggest the presence of iron-line emission in the spectrum of
  the source at an energy of 6.6 + 0.2 keV. The counts due to the line
  are in excess of the continuum and background counts by 6 standard
  deviations. A comparison of the observed line-to-continuum ratio with
  calculations yields a value consistent with a normal cosmic abundance
  of iron in the source.

---------------------------------------------------------
Title: Iron Line Emission at 1.9 Å during Solar Flares
Authors: Culhane, J. L.; Phillips, K. J. H.
1970ApJ...160..309C    Altcode:
  Solar X-ray spectra have been obtained with a proportional-counte
  spectrometer on board the Orbiting Sotar Observatory 4. Observations
  of an iron line at around t.9 A are presented which suggest that the
  line is nonthermally excited.

---------------------------------------------------------
Title: A simplified thermal continuum functionfor the X-ray emission
    from coronal plasmas
Authors: Culhane, J. L.; Acton, L. W.
1970MNRAS.151..141C    Altcode:
  At temperatures below x io6 0K, the free-bound process makes an
  increasingly significant contribution to the total continuum flux. While
  the free-free spectrum may be represented by a relatively simple
  expression, a detailed calculation of the spectrum requires a lengthy
  summation process over all the ionization stages and levels of the
  abundant coronal ions. A simple empirical expression is presented which
  gives the magnitude and spectral slope of the free-bound contribution
  over the energy interval - for the temperature range 4 2ooxIo60K. This
  expression gives results that agree to better than 15 per cent with
  more detailed calculations of the thermal continuous spectrum.

---------------------------------------------------------
Title: Techniques for Improving the Sensitivity of Proportional
    Counters Used in X-Ray Astronomy
Authors: Sanford, P. W.; Cruise, A. M.; Culhane, J. L.
1970IAUS...37...35S    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Solar X-Ray Bursts at Energies Less than 10 keV Observed
    with OSO-4
Authors: Culhane, J. L.; Phillips, K. J. H.
1970SoPh...11..117C    Altcode:
  Using data from a proportional counter spectrometer, sensitive in the
  wavelength range 1-20 Å, on OSO-4, X-ray bursts in the energy band 3.0
  to 4.5 keV have been studied. 150 events have been identified between
  October 27, 1967 and May 8, 1968, mostly of an impulsive nature. Some
  gradual rise and fall bursts occur, but there is a selection bias
  against such long-enduring events. A study of the profiles of these
  events reveals no basis for identifying different types of impulsive
  event.

---------------------------------------------------------
Title: Soft X-Ray Observations from OSO-4
Authors: Culhane, J. L.; Sanford, P. W.; Phillips, K. J. H.
1969S&T....37..287C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: A study of the solar soft X-ray spectrum
Authors: Culhane, J. L.; Sanford, P. W.; Shaw, M. L.; Phillips,
   K. J. H.; Willmore, A. P.; Bowen, P. J.; Pounds, K. A.; Smith, D. G.
1969MNRAS.145..435C    Altcode:
  A proportional counter X-ray spectrometer, sensitive in the
  wavelength ranges 1-20 A and o A, was placed in orbit on the
  Orbiting Solar Observatory -4. The instrument began to acquire data
  on 1967 October 23. The spectrometer and its operation are briefly
  described. Its performance and the method of data analyses are also
  discussed. Preliminary studies have been made of the slowly varying
  component of solar X-radiation, the nature of the X-ray active regions
  in the solar corona and the characteristics of impulsive X-ray events.

---------------------------------------------------------
Title: Thermal continuum radiation from coronal plasmas at soft
    X-ray wavelengths
Authors: Culhane, J. L.
1969MNRAS.144..375C    Altcode:
  The continuous spectra, arising from the and transitions of electrons
  in coronal plasmas, are calculated for wavelengths in the range IA
  to 3oA and at temperatures in the range 106 K to 106 K. The effect of
  variations in the element abundances is investigated. Estimates of the
  continuum flux from the solar corona are presented and the observed
  line to continuum ratios discussed.

---------------------------------------------------------
Title: Observations of solar X-ray activity with a proportional
    counter spectrometer on OSO-IV
Authors: Culhane, J. L.; Sanford, P. W.; Shaw, M. L.; Pounds, K. A.;
   Smith, D. G.
1969sfsr.conf..131C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: Prelimiary Results of Soalr X-Ray Studies With a Proportionall
    Counter Spectrometer on OSO-IV
Authors: Culhane, J. L.; Sanford, P. W.; Shaw, M. L.
1968AJS....73S..58C    Altcode:
  No abstract at ADS

---------------------------------------------------------
Title: A measurement of the solar X-ray flux in the wavelength range
    below 5 Å
Authors: Bowles, J. A.; Culhane, J. L.; Sanford, P. W.; Shaw, M. L.;
   Cooke, B. A.; Pounds, K. A.
1967P&SS...15..931B    Altcode:
  Two beryllium windowed proportional counters were used to measure the
  solar X-ray flux in the wavelength band below 5 Å. They were flown on
  a Centaure rocket launched from a site near Karystos in Greece. The
  counters and their associated electronics are briefly described. The
  shape of the spectrum is estimated by considering the variation
  in counting rate as the rocket ascended through the atmosphere. A
  comparison of the present result with other measurements suggests that
  the spectral slope and intensity are extremely variable in this part
  of the spectrum.

---------------------------------------------------------
Title: X-ray astronomy of the Sun
Authors: Culhane, J. L.
1966PhDT.......114C    Altcode:
  This thesis is concerned with the study of soft X-radiation from
  the Sun. The properties of the Solar Corona are briefly reviewed
  and possible mechanisms for the production of X-rays in the Corona
  are critically discussed. <P />The proportional counter is used as a
  spectrometer throughout the work so the operation of this detector is
  considered in detail. In particular its energy resolution and limits
  of proportionality are examined. <P />The continuous X-ray spectrum
  of the Sun has been calculated and compared with proportional counter
  observations under both quiet and disturbed Solar conditions. <P
  />Finally two new experiments are described. One is a rocket experiment
  designed to study the radiation from the Sun in the 20 - 70A band,
  while the other is a satellite experiment which is designed to study
  the Solar radiation in the 1 - 20A band in considerable detail.

---------------------------------------------------------
Title: Variability of the solar X-ray spectrum below 15 A
Authors: Culhane, J. L.; Willmore, A. P.; Pounds, K. A.; Sanford, P. W.
1964spre.conf..741C    Altcode:
  No abstract at ADS