Author name code: bentley
ADS astronomy entries on 2022-09-14
author:"Bentley, Robert D." 
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Title: Constraining the Binarity of the S-stars Orbiting the Central
    Supermassive Black Hole Using Radial Velocities
Authors: Chu, D. S.; Do, T.; Ghez, A.; Hees, A.; Ciurlo, A.; Gautam,
   A.; O'neil, K. K.; Hosek, M. W., Jr.; Chen, Z.; Sakai, S.; Lu, J. R.;
   Bentley, R.
Bibcode: 2021ASPC..528..321C
Altcode:
  The formation mechanism of the young S-stars located within an arcsecond
  of the central supermassive black hole remains a mystery. While binaries
  are important for understanding the young star cluster at the Galactic
  Center, there have been limited surveys for binaries in the region. We
  present a framework for searching for spectroscopic binaries. With over
  two decades of integral field spectroscopy data and advanced tools
  for fitting mid-infrared stellar spectra, it is feasible to conduct
  a spectroscopic binary search of the Galactic Center S-stars. After
  subtracting a star's motion around the supermassive black hole, we
  search for a periodic signal using a Lomb-Scargle analysis and fitting
  the residual radial velocity curve to a binary system radial velocity
  curve. We find no significant periodic detections in our sample,
  suggesting there are no binaries among the S-stars. These results favor
  formation mechanisms that result in the S-stars being single stars.

Title: Search for a variation of the fine-structure constant around
    the supermassive Black Hole in our Galactic Center
Authors: Roberts, Benjamin; Hees, A.; Do, T.; Ghez, A. M.; Nishiyama,
   S.; Bentley, R.; Gautam, A. K.; Jia, S.; Kara, T.; Lu, J. R.; Saida,
   H.; Sakai, S.; Takahashi, M.; Takamori, Y.
Bibcode: 2020APS..DMPE01155R
Altcode:
  Searching for space-time variations of the constants of Nature is a
  promising way to search for new physics beyond General Relativity and
  the standard model motivated by unification theories and models of dark
  matter and dark energy. We propose a new way to search for a variation
  of the fine-structure constant using measurements of late-type evolved
  giant stars from the S-star cluster orbiting the supermassive black hole
  in our Galactic Center. A measurement of the difference between distinct
  absorption lines (with different sensitivity to the fine structure
  constant) from a star leads to a direct estimate of a variation of the
  fine structure constant between the star's location and Earth. Using
  spectroscopic measurements of 5 stars, we obtain a constraint on the
  relative variation of the fine structure constant below 1e-5. This is
  the first time a varying constant of Nature is searched for around a
  black hole and in a high gravitational potential. This analysis shows
  new ways the monitoring of stars in the Galactic Center can be used
  to probe fundamental physics.

Title: Solar Windsocks - A service to derive estimates of solar wind
    speeds from comets' ion tails
Authors: Jones, Geraint; Bentley, Robert; Ramanjooloo, Yudish
Bibcode: 2018cosp...42E1635J
Altcode:
  Comets' ion tails show material being carried away from cometary
  nuclei by the solar wind. As we know where each comet is, how fast it's
  moving, and in what direction, we can use the orientation of the tail to
  estimate the solar wind speed at the comet. Solar Windsocks is based on
  the assumption that the solar wind flow is radial, i.e. that it flows
  directly away from the Sun. This is known to not quite be true, with
  the solar wind often deviating a few degrees from the radial direction,
  but this assumption is necessary in order to derive solar wind speed
  estimates from comet images. The service takes a user's image, and
  projects it onto the comet's orbital plane. The position of the ion
  tail is then identified manually in the image, and the solar wind speed
  corresponding to each marked position in the tail is calculated. Using
  this technique, several solar wind speed estimates can be provided from
  each image. It is hoped that amateur and professional comet observers
  will donate their images and the resultant solar wind speed estimates to
  the project, to build up a database of point measurements of the flow
  speed in the inner heliosphere. The Solar Windsocks project is only
  possible through the financial support of the Europlanet-2020 Research
  Infrastructure, funded by the European Commission. Solar Windsocks is
  part of the Europlanet Planetary and Space Weather Services activity.

Title: The Economic Impact of Space Weather: Where Do We Stand?
Authors: Eastwood, J. P.; Biffis, E.; Hapgood, M. A.; Green, L.;
   Bisi, M. M.; Bentley, R. D.; Wicks, R.; McKinnell, L. A.; Gibbs, M.;
   Burnett, C.
Bibcode: 2017RiskA..37..206E
Altcode:
  Space weather describes the way in which the Sun, and conditions in
  space more generally, impact human activity and technology both in
  space and on the ground. It is now well understood that space weather
  represents a significant threat to infrastructure resilience, and is
  a source of risk that is wide-ranging in its impact and the pathways
  by which this impact may occur. Although space weather is growing
  rapidly as a field, work rigorously assessing the overall economic
  cost of space weather appears to be in its infancy. Here, we provide
  an initial literature review to gather and assess the quality of any
  published assessments of space weather impacts and socioeconomic
  studies. Generally speaking, there is a good volume of scientific
  peer-reviewed literature detailing the likelihood and statistics
  of different types of space weather phenomena. These phenomena all
  typically exhibit "power-law" behavior in their severity. The literature
  on documented impacts is not as extensive, with many case studies,
  but few statistical studies. The literature on the economic impacts of
  space weather is rather sparse and not as well developed when compared
  to the other sections, most probably due to the somewhat limited data
  that are available from end-users. The major risk is attached to power
  distribution systems and there is disagreement as to the severity
  of the technological footprint. This strongly controls the economic
  impact. Consequently, urgent work is required to better quantify the
  risk of future space weather events.

Title: The Heliophysics Feature Catalogue, a tool for the study of
    solar features
Authors: Bonnin, Xavier; Fuller, Nicolas; Renié, Christian;
   Aboudarham, Jean; Cecconi, Baptiste; Bentley, Robert D.; Csillaghy,
   André
Bibcode: 2014IAUS..300..512B
Altcode:
  The behavior of filaments and prominences during the Solar Cycle is
  a signature of Sun's activity. It is therefore important to follow
  their evolution during the cycle, in order to be able to associate it
  with the various phases of the Solar Cycle as well as with other Solar
  features or events. The virtual observatory HELIO provides information
  that can be used for such studies, especially its Heliophysics Feature
  Catalogue gives a unique access to the description of various features
  during around one cycle. Features available are: filaments, prominences,
  photospheric and coronal active regions, coronal radio emission, type
  III radio bursts, coronal holes and sunspots. Web interfaces allow the
  user to query data for these features. Useful information can also be
  shared with other HELIO services, such as Heliophysics Event Catalogue,
  which provides access to dozens of tables of events such as flares,
  CMEs, . . .

Title: HELIO - Discovering solar effects in all the heliosphere
Authors: Pérez-Suárez, D.; Bentley, R. D.; Aboudarham, J.; Brooke,
   J.; Csillaghy, A.; Gallagher, P. T.; Jacquey, C.; Messerotti, M.;
   Pierantoni, G.
Bibcode: 2013EPSC....8..328P
Altcode:
  HELIO, the HELiophysics Integrated Observatory, consists of a set of
  integrated software tools developed by an international consortium under
  the European Commission's Seventh Framework Programme (FP7). HELIO
  is designed to help scientists easily search heliophysical data
  and discover any possible connections. This is achieved by merging
  information from feature and event catalogues and services that know
  about the locations and capabilities of instruments to find all the data
  available that contain information on a certain event by propagating
  it through the whole solar system. There are then tools to access data
  archives and processing tools that allow the users to create their own
  workflows. <P />HELIO is definitely making the research in heliophysics
  more accessible to different scientists [1] but it capabilities goes
  further than this. It can be adapted to other fields in science,
  where multiple observations in different observatories are used to
  study a particular event. The interfaces of the HELIO services are
  based onWeb services and, as far as possible, are compliant with IVOA
  standards. This simplifies access to the capabilities via different
  tools like Web browsers, scripting languages (IDL, Python, etc.), and
  workflow tools (Taverna, Kepler, etc.). The overall capabilities of
  the system can greatly increased when the services are combined using
  workflows or scripting languages. While we try to hide the use of these
  tools for most users, those who choose to gain familiarity with such
  tools can address more complex problems. <P />A brief introduction to
  HELIO services and a use case demonstration will be presented.

Title: SHEBA - HELIO's propagation model: a walk through its
    possibilities
Authors: Pérez-Suárez, David; Pierantoni, Gabriele; Maloney, Shane
   A.; Higgins, Paul A.; Gallagher, Peter T.; Bentley, Robert D.
Bibcode: 2013EGUGA..1513919P
Altcode:
  The Heliophysics Integrated Observatory (HELIO) is a software
  infrastructure involving a collection of web services, heliospheric data
  sources (e.g., solar, planetary, etc.), and event catalogues - all of
  which are accessible through a unified front end. HELIO brings to the
  scientist the possibility to search an event occurred in the heliosphere
  and find out which other events are linked with the one under study. To
  get the relation between events HELIO uses SHEBA (Solar-Heliospheric
  Event Ballistic Algorithm), a simple propagation model for Coronal
  Mass Ejections, Solar Energetic Particle and Co-rotating Interaction
  Regions. This poster explains the basics of SHEBA and it walks through
  real-case scenarios of its use.

Title: Automation of the Filament Tracking in the Framework of the
    HELIO Project
Authors: Bonnin, X.; Aboudarham, J.; Fuller, N.; Csillaghy, A.;
   Bentley, R.
Bibcode: 2013SoPh..283...49B
Altcode: 2012arXiv1202.2072B; 2012SoPh..tmp..132B; 2012SoPh..tmp..103B
  We present a new method to automatically track filaments over the solar
  disk. The filaments are first detected on Meudon Spectroheliograph
  Hα images of the Sun, applying the technique developed by Fuller,
  Aboudarham, and Bentley (Solar Phys. 227, 61, 2005). This technique
  combines cleaning processes, image segmentation based on region growing,
  and morphological parameter extraction, including the determination of
  filament skeletons. The coordinates of the skeleton pixels, given in a
  heliocentric system, are then converted to a more appropriate reference
  frame that follows the rotation of the Sun surface. In such a frame,
  a co-rotating filament is always located around the same position, and
  its skeletons (extracted from each image) are thus spatially close,
  forming a group of adjacent features. In a third step, the shape of
  each skeleton is compared with its neighbours using a curve-matching
  algorithm. This step will permit us to define the probability [P]
  that two close filaments in the co-rotating frame are actually the
  same one observed on two different images. At the end, the pairs of
  features, for which the corresponding probability is greater than
  a threshold value, are associated using tracking identification
  indices. On a representative sample of filaments, the good agreement
  between automated and manual tracking confirms the reliability of the
  technique to be applied on large data sets. This code is already used
  in the framework of the Heliophysics Integrated Observatory (HELIO)
  to populate a catalogue dedicated to solar and heliospheric features
  (HFC). An extension of this method to other filament observations,
  and possibly sunspots, faculae, and coronal-holes tracking, can also
  be envisaged.

Title: The Philosophy of User Interfaces in HELIO and the Importance
    of CASSIS
Authors: Bonnin, X.; Aboudarham, J.; Renié, C.; Csillaghy, A.;
   Messerotti, M.; Bentley, R. D.
Bibcode: 2012ASPC..461..303B
Altcode: 2012adass..21..303B
  HELIO is a European project funded under FP7 (Project No. 238969). One
  of its goals as a Heliospheric Virtual Observatory is to provide an easy
  access to many datasets scattered all over the world, in the fields
  of Solar physics, Heliophysics, and Planetary magnetospheres. The
  efficiency of such a tool is very much related to the quality of the
  user interface. HELIO infrastructure is based on a Service Oriented
  Architecture (SOA), regrouping a network of standalone components,
  which allows four main types of interfaces: - HELIO Front End
  (HFE) is a browser-based user interface, which offers a centralized
  access to the HELIO main functionalities. Especially, it provides
  the possibility to reach data directly, or to refine selection by
  determination of observing characteristics, such as which instrument
  was observing at that time, which instrument was at this location,
  etc. - Many services/components provide their own standalone graphical
  user interface. While one can directly access individually each
  of these interfaces, they can also be connected together. - Most
  services also provide direct access for any tools through a public
  interface. A small java library, called Java API, simplifies this
  access by providing client stubs for services and shields the user
  from security, discovery and failover issues. - Workflows capabilities
  are available in HELIO, allowing complex combination of queries over
  several services. We want the user to be able to navigate easily,
  at his needs, through the various interfaces, and possibly use a
  specific one in order to make much-dedicated queries. We will also
  emphasize the importance of the CASSIS project (Coordination Action
  for the integration of Solar System Infrastructure and Science) in
  encouraging the interoperability necessary to undertake scientific
  studies that span disciplinary boundaries. If related projects follow
  the guidelines being developed by CASSIS then using external resources
  with HELIO will be greatly simplified.

Title: Combining observations to study heliospheric phenomena
Authors: Bentley, R. D.
Bibcode: 2012epsc.conf..556B
Altcode: 2012espc.conf..556B
  There is currently a more diverse range of observatories scattered
  around the solar system than at any time in the past. As a consequence,
  heliophysics - the study of the effect of the Sun on the Solar System
  - has entered a boom period. The Heliophysics Integrated Observatory,
  HELIO, has established a collaborative environment where scientists can
  discover, understand and model the connection between solar phenomena,
  interplanetary disturbances and their effects on the planets. The
  project is designed around a serviceoriented architecture with needed
  capabilities that support metadata curation and search, data location
  and retrieval, and data processing and storage being established as
  independent services. HELIO provides integrated access to the data
  and metadata from the domains that constitute heliophysics - solar,
  heliospheric, geophysics and planetary. More than 50 event catalogues
  can be used in the search, together with10 feature catalogues;
  data from more than 150 instruments from nearly 50 observatories
  can be accessed. A comprehensive user interface is available and the
  services can also be accessed through IDL; a workflow tool provides
  the ability to combine services together and it is possible to execute
  programmes on demand including propagation models. We will show how
  HELIO can be used to explore how phenomena evolve as they propagate
  through the Solar System. Effects related to structures in the solar
  wind, coronal mass ejections and particle events are reported using
  observations from multiple platforms, including occasions where the
  same phenomenon interacts with multiple planetary environments. The
  HELIO Consortium includes thirteen groups from the UK, France, Ireland,
  Italy, Switzerland, Spain and the US; the project started in June 2009
  and has a duration of 42 months.

Title: HELIO: A Heliospheric Virtual Observatory
Authors: Aboudarham, J.; Bentley, R. D.; Csillaghy, A.
Bibcode: 2012ASPC..461..255A
Altcode: 2012adass..21..255A
  HELIO, the Heliophysics Integrated Observatory, is a Research
  Infrastructure funded under EC's FP7 Capacities Specific Programme. It
  began in June 2009 for three years. It will provide the heliophysics
  research community with an integrated e-infrastructure that
  has no equivalent anywhere else. The project objectives are as
  follows: - to create a collaborative environment where scientists
  can discover, understand and model the connection between solar
  phenomena, interplanetary disturbances and their effects on the
  planets (esp. the Earth) - to establish a consensus on standards
  for describing all heliophysical data and champion them within
  international standards bodies, e.g. the IVOA - to develop new ways
  to interact with a virtual observatory that are more closely aligned
  with the way researchers wish to use the data. HELIO is based on a
  Service-Oriented architecture. For this purpose, HELIO developed a
  Front End, which facilitates the search for data, using series of search
  metadata services covering different domains (many Events and Features
  available; use of context information to refine selection); Services
  to identify and retrieve observations based on search results (knows
  which data are stored where and how to access them); Enabling services
  such as tools to find and track events/phenomena in 4D environment
  (i.e. including the propagation of phenomena). Services can be used
  individually or combined through workflow capability. Heliophysics
  Event Catalogue and Heliophysics Features Catalogue provide a specific
  access to information concerning phenomena that occur in the Solar
  system. A semantic-driven approach is used to integrate data from
  different domains, based on ontology derived from existing data
  models. Thirteen partners from Europe and US are involved in this
  project. And although it is not completed, a prototype is already
  available, which can be accessed through HELIO web site (&lt;a
  href='http://www.helio-vo.eu/'&gt;http://www.helio-vo.eu/&lt;/a&gt;).

Title: The role of e-Infrastructures supporting Solar System science
    within general research environments
Authors: Bentley, R. D.
Bibcode: 2012epsc.conf..557B
Altcode: 2012espc.conf..557B
  Many aspects of Solar System science are related with phenomena
  observed on the Sun subsequently causing effects in other parts of
  the Solar System; similarly, effects that originate in heliopshere
  or the near planetary environments can have impacts low down in
  planetary atmospheres. However, combining and comparing observations
  from the different domains is more difficult that it should be,
  partly because the communities have evolved independently without
  any consideration of the need for interoperability. A number of
  e-Infrastructures have been established to support the analysis
  in different aspect of science within the Solar System - some have
  been funded under FP7 including Europlanet RI and HELIO. Now that
  the Research Infrastructures are reaching maturity it is important
  to examine how they might work better together and be combined to
  support new types of science. The infrastructure established by HELIO
  follows a service oriented architecture where required capabilities are
  implemented as independent services that cam be combined as needed. If
  the capabilities of other infrastructures can be made available in
  a similar way then it is possible to consider them all as components
  in a larger and more general collaborative research environment that
  can be used to address science use cases that were previously not
  possible. We discuss how this might be achieved and describe some
  of the ideas being developed under the Coordination Action for the
  integration of Solar System Infrastructure and Science (CASSIS).

Title: A Collaborative Research Environment for Heliophysics
Authors: Bentley, R. D.; Berghmans, D.; Csillaghy, A.
Bibcode: 2012EGUGA..1412873B
Altcode:
  Heliophysics is the study of the effect of the Sun on the Solar
  System; it is a relatively new science that combines the solar,
  heliospheric, geophysics and planetary communities. The subject is
  an example of the increasing desire to address science problems that
  span disciplinary boundaries and provides a good example of the issues
  involved. The communities that constitute heliophysics have grown up
  independently and there are differences in the way that their data
  are stored and used. Although a number of capabilities relevant to
  heliophysics have been established under auspices of various projects
  and organisations, the fact that they have not followed any underlying
  strategy is now inhibiting our ability to do this type of science. The
  Heliophysics Integrated Observatory (HELIO), a research infrastructure
  funded under Capacities programme of the EC's 7th Framework Programme
  (FP7), was designed around a service-oriented architecture with needed
  capabilities that support metadata curation and search, data location
  and retrieval, and data processing and storage being established as
  independent services. In addition, a number of virtual observatories
  have been established that address aspects of the overall problem
  of heliophysics within the NASA's Heliophysics Science Division. We
  examine the capabilities of these resources and look at where their
  strengths and weaknesses lie. We identify some of the steps that are
  needed to improve interoperability between the initiatives and consider
  how they could be brought together to form a Collaborative Research
  Environment for Heliophysics (CREH). The Coordination Action for the
  integration of Solar System Infrastructure and Science (CASSIS) has the
  objective of exploring ways to improve interoperability for all aspects
  of Solar System Science. CASSIS is funded under Capacities specific
  programme of the European Commission's Seventh Framework Programme
  (FP7) and grew out of the HELIO, Europlanet RI and SOTERIA projects;
  it also includes other key partners such as NASA, ESA, and NOAA. We
  welcome participation by other interested organisations

Title: HELIO - A Research Environment for Heliophysics
Authors: Bentley, R. D.; Abourdarham, J.; Csillaghy, A.; Messerotti,
   M.; Gallagher, P.; Bocchialini, K.; Jacquey, C.; Hapgood, M.
Bibcode: 2012EGUGA..1411634B
Altcode:
  HELIO, the Heliophysics Integrated Observatory, is a research
  infrastructure funded under Capacities programme of the EC's 7th
  Framework Programme (FP7). It provides a collaborative environment where
  scientists can discover, understand and model the connection between
  solar phenomena, interplanetary disturbances and their effects on the
  planets. The project is designed around a service-oriented architecture
  with needed capabilities that support metadata curation and search,
  data location and retrieval, and data processing and storage being
  established as independent services. HELIO provides integrated access
  to the data and metadata from the domains that constitute heliophysics
  - solar, heliospheric, geophysics and planetary. More than 50 event
  catalogues can be used in the search, together with just under 10
  feature catalogues; data from more than 150 instruments from nearly
  50 observatories can be accessed. A comprehensive user interface
  is available and the serves can also be accessed through IDL; a
  workflow tool provides the ability to combine services together and
  it is possible to execute programmes on demand including propagation
  models. We will report on the status of HELIO and the services that are
  available and demonstrate how these resources can be used to address
  use cases involving multiple spacecraft and modelling. We will also
  describe how we hope to combine the tools developed by HELIO into a
  Collaborative Research Environment for Heliophysics. We have been
  holding a series of Coordinated Data Analysis Workshops (CDAW) in
  which we demonstrate the capabilities of the project and participants
  are able to use them to address science use cases. Two CDAWs have been
  held so far, in Dublin and Trieste; a third will be held in February
  2012 in Orsay, and a fourth is planned in May/June 2012. Typical use
  cases relate to phenomena propagating from the Sun and being observed
  by at least two observatories in different parts of the inner Solar
  System. The HELIO Consortium includes thirteen groups from the UK,
  France, Ireland, Italy, Switzerland, Spain and the US; the project
  started in June 2009 and has a duration of 36 months

Title: Automated detection and tracking of solar and heliospheric
    features in the frame of the European project HELIO
Authors: Bonnin, X.; Aboudarham, J.; Fuller, N.; Renie, C.;
   Perez-Suarez, D.; Gallagher, P.; Higgins, P.; Krista, L.; Csillaghy,
   A.; Bentley, R.
Bibcode: 2011sf2a.conf..373B
Altcode:
  In the frame of the European project HELIO, the Observatoire de
  Paris-Meudon is in charge of the Heliophysics Feature Catalogue (HFC),
  a service which provides access to existing solar and heliospheric
  feature data. In order to create a catalogue as exhaustive as possible,
  recognition codes are developed to automatically detect and track
  features. At the time, HFC contains data of filaments, active regions,
  coronal holes, sunspots and type III radio bursts for a full solar
  cycle. The insertion of prominences and type II radio bursts should
  be done in the short term. We present here an overview of some of
  the algorithms used to populate HFC. The development of such fast
  and robust techniques also addresses the needs of the Space Weather
  community in terms of near real-time monitoring capabilities.

Title: The need for Standards when building Virtual Observatories
Authors: Bentley, R. D.; Csillaghy, A.; Aboudarham, J.; Messerotti,
   M.; Jacquey, C.; Capria, M. T.
Bibcode: 2011AGUFMSM21A2002B
Altcode:
  The Heliophysics Integrated Observatory, HELIO, has been established
  based on a service-oriented architecture (SAO) under which the required
  capabilities are provided as set of independent services that can be
  used and combined as required. The main services fall into two general
  groups: identifying interesting events and phenomena and locating and
  retrieving suitable observations; there are also a number of enabling
  services such as the Registry, processing and storage services,
  coordinate transformation, etc. The HELIO services can be addresses
  through SOAP and REST interfaces that are based on protocols developed
  by the IVOA; for several services Web GUIs are also provided. Most
  services can produce outputs in a number of formats although the
  preferred one is VOTable, another product of the IVOA. It is important
  that projects are able to build on each other's services. By developing
  and employing standards, some services of HELIO are of immediate use to
  other projects while other could be with some modifications. Adopting
  the VOTable format has meant that it is possibly to fully describe each
  parameter in the table using annotation, unambiguously defining what
  the parameter represents. This approach makes it simpler for a service
  from a different domain to use the products of HELIO; the same ought to
  be true for other projects. In this paper we will present what has been
  achieved so far and how this can help define and refine a broader set
  of protocols. Some of this work is being done in conjunction with the
  CASSIS project that is trying to encourage the adoption of standards
  to increase the interoperability between domains. The HELIO and CASSIS
  projects are funded under the European Commission's Seventh Framework
  Programme (FP7).

Title: Using HELIO to address use cases involving multi-point
    observations from different parts of the Solar System.
Authors: Bentley, R. D.
Bibcode: 2011epsc.conf..861B
Altcode: 2011DPS....43..861B
  The Heliophysics Integrated Observatory, HELIO, is creating
  a distributed network of services that will address the needs of a
  broad community of researchers in heliophysics. It provides integrated
  access to data from the solar and heliospheric communities, and to
  magnetospheric and ionospheric data from the geophysics and planetary
  communities. HELIO is now in its third year and almost all the services
  define in the architectural design have been deployed and can be used
  by the community. It can be used to address science use cases that
  span disciplinary boundaries and the capabilities of the project are
  evolving as the system is being used in this way. Many of the services
  have important capabilities but two key achievements are that the event
  catalogue contains more than 40 event lists from various communities
  and the access service provides access to more than 160 instruments
  from over 45 observatories. We will report on the current status of
  the and illustrate how HELIO can be used to address some of the use
  cases. HELIO is a Research Infrastructures funded under the Capacities
  Specific Programme within the European Commission's Seventh Framework
  Programme (FP7; Project No. 238969).

Title: CASSIS - Standards and Interoperability in Solar System Science
Authors: Bentley, R. D.
Bibcode: 2011epsc.conf..862B
Altcode: 2011DPS....43..862B
  There is an increasing desire to address science problems that
  span many disciplines; in heliophysics this includes solar and
  heliospheric physics, planetary science, and magnetospheric and
  ionospheric physics. However, differences in the way that data are
  stored and used by the communities involves are inhibiting our ability
  to do this type of science. We examine virtual observatories and data
  archives that are available in heliophysics and related disciplines,
  compare their capabilities and look at where their strengths and
  weaknesses lie. We identify some of the steps that are needed to
  improve interoperability between the VO initiatives and propose that
  discussions under the auspices of CASSIS could help us globally to
  move towards this overall objective. The Coordination Action for the
  integration of Solar System Infrastructure and Science, CASSIS, is
  funded under Capacities specific programme of the European Commission'
  Seventh Framework Programme (FP7) and has the objective of exploring
  ways to improve interoperability for all aspects of Solar System
  Science. CASSIS grew out of the HELIO, Europlanet RI and SOTERIA
  projects and also includes other key partners, including NASA, ESA,
  and NOAA. We welcome participation by other interested organisations.

Title: HELIO: The Heliophysics Integrated Observatory
Authors: Bentley, R. D.; Csillaghy, A.; Aboudarham, J.; Jacquey, C.;
   Hapgood, M. A.; Bocchialini, K.; Messerotti, M.; Brooke, J.; Gallagher,
   P.; Fox, P.; Hurlburt, N.; Roberts, D. A.; Duarte, L. Sanchez
Bibcode: 2011AdSpR..47.2235B
Altcode:
  Heliophysics is a new research field that explores the Sun-Solar System
  Connection; it requires the joint exploitation of solar, heliospheric,
  magnetospheric and ionospheric observations.HELIO, the Heliophysics
  Integrated Observatory, will facilitate this study by creating an
  integrated e-Infrastructure that has no equivalent anywhere else. It
  will be a key component of a worldwide effort to integrate heliophysics
  data and will coordinate closely with international organizations to
  exploit synergies with complementary domains.HELIO was proposed under a
  Research Infrastructure call in the Capacities Programme of the European
  Commission’s 7th Framework Programme (FP7). The project was selected
  for negotiation in January 2009; following a successful conclusion to
  these, the project started on 1 June 2009 and will last for 36 months.

Title: The First Steps of the Heliophysics Integrated Observatory
Authors: Csillaghy, A.; Felix, S.; Bentley, R. D.; Blanc, A. L.;
   Helio Team
Bibcode: 2010ASPC..434..237C
Altcode: 2010adass..19..237C
  HELIO is the new European VO for solar and heliophysics. It develops
  a collection of web services that span an information space and
  make it possible to study solar activity and its effects on the solar
  system. The infrastructure is developed iteratively, where functionality
  slowly adds up in frequent releases and short iterations. The services
  are integrated by the Taverna workflow orchestration tool.

Title: VOs and Heliophysics: Would anyone like some CASSIS?
Authors: Bentley, R. D.; Lapenta, G.; Blanc, M.; Fox, P.; Walker,
   R. J.; Cassis Team
Bibcode: 2010AGUFMIN23B1358B
Altcode:
  Virtual Observatories related to heliophysics have emerged in various
  regions of the World. Partly because of their sources of funding the
  emphasis they place on aspects of the problem differ and how well
  they can be integrated with other capabilities varies to a greater or
  lesser degree. We examine virtual observatories that are available in
  heliophysics and related disciplines and compare their capabilities and
  look at where their strengths lie. We also identify some of the steps
  that are needed to improve interoperability between the VO initiatives
  and propose that discussions under the auspices of CASSIS could
  help us globally to move towards this overall objective. CASSIS, the
  Coordination Action for the integration of Solar System Infrastructure
  and Science, is funded under Capacities specific programme of the
  European Commission' Seventh Framework Programme (FP7) and has the
  objective of exploring ways to improve interoperability for all aspects
  of Solar System Science. CASSIS grew out of the HELIO, Europlanet RI
  and SOTERIA projects and also includes other key partners, including
  NASA, ESA, and NOAA. We welcome participation by other interested
  organisations.

Title: HELIO - First Services of The Heliophysics Integrated
    Observatory
Authors: Csillaghy, A.; Bentley, R. D.
Bibcode: 2010AGUFMIN23B1359C
Altcode:
  Heliophysics is a new science exploring the Sun-Solar System
  connection. It spans the existing domains of solar, heliospheric,
  magnetospheric and ionospheric physics. Heliophysics influences the
  environments studied by the planetary and geosciences and also has
  relevance for the astrophysics community. HELIO is an e-Infrastructure
  project funded by the European Union 7th Framework Program. It develops
  services to support integrated access to metadata and data from the
  domains that constitute heliophysics. It also develop services to
  explore and mine the data space spanned by the information providers
  of the domains. Building up on these services, it constructs complex
  queries, for instance to find observations that track phenomena as
  they propagate through interplanetary space and affect the planetary
  environments. The infrastructure is based on a service-oriented
  architecture. It is designed to support locating and retrieving of
  data associated with the desired observations. Services in development
  are divided into four categories: catalog services (what phenomena are
  interesting?), instrument location services (what instruments observed
  the phenomena?), data access services (where are the associated
  data?), and advanced services (what can I do with these data?). A
  registry service allows keeping track of the resources managed by the
  infrastructure. HELIO services are established as stand-alone, so they
  can be used individually. Nevertheless, constructing complex queries
  requires combining services into workflows. The workflow orchestration
  tool used is called Taverna. To combine the resources from the different
  heliophysics communities, HELIO uses a semantic-driven approach which
  describe the relationships between the domains involved, therefore
  avoiding to impose a specific name space. HELIO is in its 2nd year
  of development. At this time, the basic services are available and
  being tested. For instance, the Heliophysics Event Catalog compiles
  an exhaustive list of solar phenomena. Focus is increasingly given
  on constructing classes of workflows able to address specific science
  objectives.

Title: HELIO - A step into the Future
Authors: Bentley, R.
Bibcode: 2010epsc.conf..870B
Altcode:
  No abstract at ADS

Title: HELIO - The Heliophysics Integrated Observatory
Authors: Bentley, R. D.; Csillaghy, A.; Abourdarham, J.
Bibcode: 2010EGUGA..1215437B
Altcode:
  HELIO, the Heliophysics Integrated Observatory, is a research
  infrastructure funded under Capacities programme of the EC's 7th
  Framework Programme (FP7). The project is creating a collaborative
  environment where scientists can discover, understand and model the
  connection between solar phenomena, interplanetary disturbances and
  their effects on the planets (esp. the Earth) HELIO will provide
  integrated access to metadata from the domains that constitute
  heliophysics - solar, heliospheric, magnetospheric and ionospheric
  physics - in order to track phenomena as they propagate through inter
  planetary space and affect the planetary environments. It will provide
  services to locate and retrieve the desired observations and return them
  to the user. HELIO is designed around a service-oriented architecture
  (SAO); many of the resources are being established as stand-alone
  services that support metadata curation and search, data location and
  retrievel, data processing and storage; it will be possible to use
  the services independently or bound into a system through a workflow
  capability. We will describe the architecture of HELIO report on the
  status of its development, including when individual services will
  become available and what their capabilities will be. The project has a
  strong Networking component and through this we wish to involve other
  groups and individuals who can help us achieve our goals. One of the
  main ways that we will involve the community is through a series of
  Coordinated Data Analysis Workshops (CDAWs); we will describe the
  preparation for the first of these which will be held in November
  2010. The HELIO Consortium includes thirteen groups from the UK, France,
  Ireland, Italy, Switzerland, Spain and the US; the project started in
  June 2009 and has a duration of 36 months.

Title: Using HELIO as tool for Research into Space Weather
Authors: Bentley, R. D.; Messerotti, M.; Aboudarham, J.; Hapgood,
   M.; Jacquey, C.; Helio Team
Bibcode: 2010EGUGA..1215417B
Altcode:
  HELIO, the Heliophysics Integrated Observatory, is a research
  infrastructure funded under Capacities programme of the EC's 7th
  Framework Programme (FP7). The project is creating a collaborative
  environment where scientists can discover, understand and model the
  connection between solar phenomena, interplanetary disturbances and
  their effects on the planets. HELIO will provide integrated access
  to metadata from the domains that constitute heliophysics - solar,
  heliospheric, magnetospheric and ionospheric physics - in order to
  track phenomena as they propagate through inter planetary space and
  affect the planetary environments. It will provide services to locate
  and retrieve the desired observations and return them to the user. The
  capabilities provided by HELIO will allow the user to undertake
  extensive studies of the origins of events that produce space weather
  effects on the Earth's environment. It will also make it possible to
  follow the causal phenomena as they pass through other parts of the
  Solar System. We will discuss these possibilities giving examples of
  how the services provided by HELIO can be used as part of a work flow
  or as stand-alone capabilities. Although the HELIO infrastructure
  is not specifically designed to provide real-time access to data,
  it might be possible to support such access if resources that are
  included have this capability. This will also be discussed. The HELIO
  Consortium includes thirteen groups from the UK, France, Ireland,
  Italy, Switzerland, Spain and the US; the project started in June 2009
  and has a duration of 36 months

Title: Data Management within the HELIO project
Authors: Bentley, Robert; Jacquey, Christian; Messerotti, Mauro;
   Csillaghy, Andre; King, Todd; Perry, Chris
Bibcode: 2010cosp...38..813B
Altcode: 2010cosp.meet..813B
  The Heliophysics Integrated Observatory, HELIO, is creating a
  collaborative environment where scientists can discover, understand
  and model the connection between solar phenomena, inter-planetary
  disturbances and their effects on the planets. Of necessity HELIO has to
  address data providers in a number of different and well established
  communities, each with its own way of describing and handling the
  data; the capabilities of the providers and means of access to
  the data also vary considerably. HELIO is being developed around a
  service-oriented architecture and the search for interesting events
  an phenomena, and the task of then finding and retrieving the data
  has been split into a number of services that can be used either as
  part of a work flow or independently. We will describe the techniques
  that we are developing for the project and will also highlight some
  areas where a joint approach by the the wider community is required
  to address some issues. The type of access that HELIO will afford is
  also of interested to related communities, including the planetary
  and geo-sciences, and astrophysics. It is therefore important that
  the products of HELIO are interoperable those communities and where
  possible we have tried to build on standards developed by bodies such
  as the IVOA, IPDA, IAU, etc. HELIO is a research infrastructure funded
  under Capacities programme of the EC's 7th Frame-work Programme (FP7);
  the project started in June 2009 and has a duration of 36 months. The
  HELIO Consortium includes thirteen groups from the UK, France, Ireland,
  Italy, Switzerland, Spain and the US.

Title: Using HELIO to study cross-disiplinary science problems using
    data from multiple spacecraft
Authors: Bentley, Robert; Aboudarham, Jean; Messerotti, Mauro; Jacquey,
   Christian; Gallagher, Peter T.; Hapgood, Mike; Bocchialini, Karine
Bibcode: 2010cosp...38.1917B
Altcode: 2010cosp.meet.1917B
  The Heliophysics Integrated Observatory, HELIO, is creating a
  collaborative environment where scientists can discover, understand
  and model the connection between solar phenomena, inter-planetary
  disturbances and their effects on the planets. HELIO will provide
  integrated access to data from the solar, heliospheric, geophysics
  and plan-etary domains and allow the user to undertake a search for
  interesting events and phenomena based solely on metadata and data
  products. The HELIO infrastructure will provide services to support
  the search that can either be used independently or as part of a work
  flow. The services include event and feature catalogues derived from
  data from all the domains and a processing capability that will use
  models to relate observations made in different part of the solar
  system. We will describe how HELIO can be used to address science
  problems that span the domains by allowing the user to track phenomena
  as they propagate through the solar system and report on progress
  to date. HELIO is a research infrastructure funded under Capacities
  programme of the EC's 7th Frame-work Programme (FP7); the project
  started in June 2009 and has a duration of 36 months. The HELIO
  Consortium includes thirteen groups from the UK, France, Ireland,
  Italy, Switzerland, Spain and the US.

Title: HELIO as a Space Weather tool
Authors: Bentley, Robert; Hapgood, Mike; Messerotti, Mauro; Aboudarham,
   Jean; Jacquey, Christian; Fox, Peter
Bibcode: 2010cosp...38.4171B
Altcode: 2010cosp.meet.4171B
  The Heliophysics Integrated Observatory, HELIO, is primarily designed
  to support research into the connection between solar phenomena,
  interplanetary disturbances and their effects on the planets. However,
  many of the techniques that are being developed and standards that we
  are proposing have direct relevance to the more immediate requirements
  of the space weather community. HELIO is being developed around
  a service-oriented architecture and the services that can be used
  either independently or as part of a work flow. The HELIO event and
  feature catalogues, context service and metadata evaluation service may
  all be of use to the community as capa-bilities in their own right;
  they could also be combined in workflows that are specific to the
  needs of research into space-weather. We have been examining ways of
  enhancing the quality of the output produced by the services by adding
  annotation that is compliant with standards proposed by the IVOA,
  IPDA and IAU; if adopted across the space weather community these
  additions could improve the interoperability of our data products
  with related communities. Of necessity HELIO has to address data
  providers in a number of different and well estab-lished communities,
  each with its own way of describing and handling the data; in addition,
  the capabilities of the providers and means of access to the data also
  vary considerably. We have therefore had to develop techniques to handle
  this, including archives where interesting observations may be available
  but not easily accessible. HELIO is a research infrastructure funded
  under Capacities programme of the EC's 7th Frame-work Programme (FP7);
  the project started in June 2009 and has a duration of 36 months. The
  HELIO Consortium includes thirteen groups from the UK, France, Ireland,
  Italy, Switzerland, Spain and the US.

Title: Addressing Science Use Cases with HELIO
Authors: Bentley, R. D.; Aboudarham, J.; Csillaghy, A.; Jacquey,
   C.; Hapgood, M. A.; Messerotti, M.; Gallagher, P.; Bocchialini, K.;
   Hurlburt, N. E.; Roberts, D.; Sanchez Duarte, L.
Bibcode: 2009AGUFMSH54A..06B
Altcode:
  The Heliophysics Integrated Observatory (HELIO) is a new VO project
  funded under the EC's Seventh Framework Programme (FP7). It includes
  thirteen partners scattered over six countries and is led by University
  College London. HELIO is designed to support the heliophysics community
  and is based on a Service Oriented Architecture. The services developed
  by and integrated into HELIO can be used to address a wide range
  of science problems; they can be used individually or as part of a
  work-flow driven search engine that can use a propagation (or other)
  model to help locate obervations that describe interesting phenomena. We
  will describe and discuss how the components of HELIO could be used
  to address science use cases, particularly how a user can adapt the
  work flow to their own science interests. Networking is one of the
  three Activities of the HELIO Integrated Infrastructure Initiatives
  (I3) project. Within this activity we plan to involve the community in
  all aspects of the design and testing of the HELIO system, including
  determining which data and metadata should be included, how the quality
  and content of metadata can be included, etc. We are investigating ways
  of making HELIO "domain-aware" so that researchers who are specialists
  in one of the communities that constitute heliophysics can easily
  identify, access and use data they need from the other communities. We
  will discuss how the community can help us develop this capability.

Title: Science, VxOs and Just In Time Information
Authors: King, T. A.; Walker, R. J.; Merka, J.; Bentley, R. D.;
   Roberts, A.; Rankin, R.; Candey, R. M.; Narock, T. W.
Bibcode: 2009AGUFMSH51B1285K
Altcode:
  The scientific method is a system for acquiring knowledge based on
  the collection of data through observation, experimentation and the
  integration of previous knowledge. This is followed by the formulation
  and testing of hypotheses resulting in new knowledge and possibly the
  correction previous knowledge. From a system design perspective the
  scientific method is a well defined system, use cases are abundant,
  requirements are readily accessible and guiding principles are
  fully articulated. With advancement of technology new implementations
  emerge to support and enable science. We are now in the age of Virtual
  Observatories where distributed data are coupled through services and
  well-defined metadata. The paradigm is one in which information is
  sought and retrieved just in time for its use. We discuss a system
  model for a Just In Time Information (JITI) system that addresses
  the clearly identified needs of scientists. It includes tasks such as
  coordinate system conversion, file format transformation, subsetting,
  aggregation, and rendering. We also discuss the discovery needs of the
  scientist which range from the initial discovery of available resources
  to complex scientific queries. Overall the system is composed of a
  collection of small services which are tied together on a task-by-task
  basis, similar to that of a workflow, but with distributed and loosely
  coupled components. In a JITI system each service is invoked as needed
  with unique resource identifiers passed as the common reference thread
  that enables the service integration. The services that are part of a
  JITI system can be utilized in a number of ways to implement portals,
  search engines, aggregators, and mash-ups. JITI-like systems are
  emerging in the Virtual Observatory communities. We look at NASA's
  Virtual Magnetospheric Observatory, the Heliophysics Event List Manager
  (HELM), Europe's HELIO project and Canada's CSSDP project as examples.

Title: HELIO and EuroPlaNet IDIS
Authors: Bentley, R. D.
Bibcode: 2009epsc.conf..814B
Altcode:
  No abstract at ADS

Title: HELIO - The Heliophysics Integrated Observatory
Authors: Bentley, R. D.; Csillahghy, A.; Aboudarham, J.
Bibcode: 2009epsc.conf..744B
Altcode:
  No abstract at ADS

Title: Payloads with Resource-Efficient Integration for Science
    Missions (PRISM)
Authors: Emam, O.; FitzGeorge, T.; Whittaker, A.; Wishart, A.; Fowell,
   S.; Prochazka, M.; Bentley, R.; Cole, R.; Brown, P.; Carr, C.; Cupido,
   E.; Oddy, T.
Bibcode: 2009ESASP.669E...7E
Altcode:
  PRISM is a collaborative industry and academia project to demonstrate
  the practicality of a highly integrated payload processing architecture,
  in order to exploit improvements in spacecraft computer performance to
  reduce multi-instrument payload mass and power requirements. Integrated
  architectures also provide opportunities for a greater degree
  of autonomy and advanced target selection (e.g. inter-instrument
  triggering). The PRISM architecture has potential advantages for
  missions such as EJSM (Europa Jupiter System Mission) or Solar
  Orbiter. The key technology objectives of PRISM are application
  partitioning on a qualifiable operating system, supported by the
  software required for fault-tolerant centralised processing, and the
  development of an application development environment for writing
  and testing instrument control applications. A working demonstrator
  has been implemented on a LEON3 platform, with representative payload
  applications from an in-situ magnetometer and a remote sensing extreme
  ultra-violet imager, both proposed for Solar Orbiter. PRISM is supported
  by the UK Science and Technology Facilities Council (STFC).

Title: HELIO - The Heliophysics Integrated Observatory
Authors: Bentley, R. D.; Csillaghy, A.; Abourdarham, J.
Bibcode: 2009EGUGA..1110375B
Altcode:
  Heliophysics is a new science that explores the Sun-Solar System
  connection and spans the existing domains of solar, heliospheric,
  magnetospheric and ionospheric physics. Heliophysics influences the
  environments studied by the planetary and geo-sciences and also has
  relevance for the astrophysics community. HELIO, the Heliophysics
  Integrated Observatory, with provide integrated access to metadata from
  the domains that constitute heliophysics in order to facilitate the
  search for observations that track phenomena as they propagate through
  inter planetary space and affect the planetary environments. It will
  provide services to locate and retrieve the desired observations and
  return them to the user in the format they require. HELIO is designed
  around a service-oriented architecture (SAO); many of the resources
  will be established as stand-alone services that support metadata
  curation and search, data location and retrievel, data processing
  and storage. It will be possible to use the services independently or
  bound into a system through a workflow capability. A semantic-driven
  approach will be used to describe the relationships between the domains
  and support the search and data retrieval capabilities. The HELIO
  Consortium includes twelve groups from the UK, France, Ireland, Italy,
  Switzerland and the US. The project has a strong Networking component
  and through this we wish to involve other groups and individuals who
  can help us achieve our goals. The HELIO proposal was submitted under
  the EC's 7th Framework Programme.

Title: Building a Virtual Observatory for Heliophysics
Authors: Bentley, R. D.
Bibcode: 2009EM&P..104...87B
Altcode:
  Heliophysics is a new discipline that studies of the effect of the
  Sun on the Solar System and spans a number of existing scientific
  domains—solar physics, heliospheric physics, and magnetospheric
  and ionospheric physics. In order to build a virtual observatory for
  heliophysics we have to find ways to conduct searches that span the
  domains and track the evolution of phenomena in 4 dimensions as they
  propagate through interplanetary space. To facilitate this it will
  be necessary to improve the quality of the metadata that are used in
  the search and to describe the observations. We describe some of the
  issues and how these can be addressed.

Title: Division XII / Commission 5 / Working Group Virtual
    Observatories, Data Centers &amp; Networks
Authors: Hanisch, Robert J.; Barbuy, Beatriz; Bentley, Robert D.;
   Benvenuti, Piero; Egret, Daniel; Fukushima, Toshio; Genova, Françoise;
   Grosbol, Preben J.; Helou, George; Norris, Raymond P.; Quinn, Peter
Bibcode: 2009IAUTA..27..369H
Altcode:
  The Working Group Virtual Observatories, Data Centers, and Networks
  was established under Commission 5 at the Prague General Assembly
  in 2006. The purpose of the WG is to provide IAU oversight of the
  activities of the International Virtual Observatory Alliance (IVOA,
  &lt;www.ivoa.net/&gt;), to encourage data centers and other data
  providers to archive and publish data according to IVOA standards, and
  to help assure that astronomical research facilities are electronically
  linked with current network technologies. The WG coordinates activities
  closely with the WG-FITS, as the IVOA uses FITS as its primary format
  for binary data exchange, and the WG on Astronomical Data.

Title: Accessing the EGSO Grid through a WSRF-Enabled API
Authors: Csillaghy, A.; Soldati, M.; Kunz, P.; Bentley, R. D.;
   Scholl, I.
Bibcode: 2006ASPC..351..536C
Altcode: 2006adass..15..536C
  EGSO is part of the Virtual Solar Observatory. It provides a Grid
  for integrated access to distributed and heterogeneous solar data
  archives. Here we describe the motivation and approach we have chosen
  to implement the Grid access as a stateful web service. Using this
  kind of service allows us to consider the search and retrieval of data
  as an interaction between the client and the Grid. This way, the EGSO
  service can be merged into interactive data analysis systems such as
  Python or IDL.

Title: The VO in Sunlight
Authors: Csillaghy, A.; Bentley, R. D.; Scholl, I.; Egso Team
Bibcode: 2006vopc.conf..343C
Altcode:
  The European Grid of Solar Observations (EGSO, www.egso.org) is a grid
  test platform that has been funded by the European Commission's Fifth
  Framework Program under its Information Society Technologies (IST)
  thematic priority. The goal of this 3-year project was to provide
  enhanced access to solar and related data around the world. In this
  paper we present the generic query model on which EGSO is built. We
  then show, from a user point of view, how it can be used for evaluating
  integrated queries that involve a large number of distributed data
  archives. We further introduce the search registries and catalogs
  on which EGSO services rely, and finally discuss the architecture of
  our system.

Title: A New Way to look at Observations with EGSO
Authors: Aboudarham, J.; Scholl, I.; Fuller, N.; Csillaghy, A.;
   Bentley, R. D.; Antonucci, E.; Ciminiera, L.; Finkelstein, A.; Ipson,
   S.; Messerotti, M.; Pike, D.; Vial, J. C.; Zharkova, V.
Bibcode: 2006IAUS..233..229A
Altcode:
  The European Grid of Solar Observations (EGSO) is a Solar virtual
  observatory (see Hill et al., 2002). It has been funded through the 5th
  Framework Program of the European Community. A dozen of laboratories,
  mixing Solar Physics and Information Technology, in Great Britain,
  France, Italy and Swiss have been involved in this project during
  3 years. A grid accessing several dozens of databases and archives
  scattered all around the world has been developped as well as a Solar
  Event Catalogue and a Solar Feature Catalogue. The original aspect
  of this work consists in the possibility not only to search through
  the characteristics of observations, but also search for available
  data corresponding to specific kinds of events. So it is now very
  important to be able to follow the Sun 24 hours a day in order to
  enrich the events database for future queries. More informations on
  EGSO, catalogues and user interface can be accessd through the web
  site: http://www.egso.org/

Title: European Grid of Solar Observations (EGSO)
Authors: Aboudarham, J.; Scholl, I.; Csillaghy, A.; Bentley, R. D.;
   Antonucci, E.; Ciminiera, L.; Finkelstein, A.; Ipson, S.; Messerotti,
   M.; Pike, D.; Vial, J. C.; Zharkova, V.
Bibcode: 2006ihy..conf...18A
Altcode:
  The EGSO project addresses the problem of combining heterogeneous
  data into a single "virtual" solar data resource. Wider access to
  other catalogues is enabled, including both pre-existing lists and
  new compilations generated using feature-recognition techniques on
  existing data. Scientists are also able to perform much richer data
  searches, based on solar events. Informations concerning EGSO can be
  found at http://www.egso.org/

Title: Active region AR484 tracking with Solar Feature Catalogue
Authors: Zharkova, V.; Benkhalil, A.; Zharkov, S.; Ipson, S.; Bentley,
   R. D.
Bibcode: 2006AdSpR..37.1152Z
Altcode:
  This paper presents a morphological analysis of the active region NOAA
  AR 484 as well as its intensity and magnetic field variations associated
  with flare occurrences. The active region is tracked during a one solar
  rotation with the automated technique used in Solar Feature Catalogue
  (SFC). The location and intensity parameters of region AR484 were
  extracted from 1 minute cadence Hα solar images from the Big Bear
  observatory (BBSO), SOHO/EIT images in Fe XII, 195 Å and the SOHO/MDI
  magnetograms. During the whole period of tracking from October, 19
  until November, 11, 2003 the AR484 produced many flares of different
  significance including a few X-class flares. We investigate the total
  AR intensity variations in each band leading to a flare production and
  compare these with the magnetic field changes before and during a flare
  for five flares of different significance. Based on this comparison the
  key parameters defining the region activity in a flare production are
  found that include the resulting, or excess, flux and the ratio between
  areas covered by negative and positive pixels. These parameters can
  be used for a preliminary pre-flare classification of active regions
  in addition to other classifiers associated with a magnetic field.

Title: EGSO - A maturing VO for Solar Physics
Authors: Bentley, R. D.; Scholl, I.; Csillaghy, A.; Aboudarham, J.;
   Antonucci, E.; Gurman, J.; Hill, F.; Pike, D.; Vial, J.; Zharkova, V.
Bibcode: 2005AGUSMSH43B..01B
Altcode:
  The European Grid of Solar Observations, EGSO, is a Grid test-bed
  funded under the Information Societies Thematic Priority of the European
  Commission's Fifth Framework Programme (FP5). In the case of EGSO, the
  application chosen was the use of Grid technology to establish a virtual
  observatory for solar physics, and the project addresses the generic
  problem of how to provide access to a distributed, heterogeneous data
  set for a scattered user community. In order to identify observations
  that match a user's search criteria, EGSO has been building an
  environment that will support complex searches. Because of the absence
  of the metadata needed to tie the heterogeneous data together, EGSO has
  placed emphasis on the provision of databases that can be accessed from
  the Internet through special providers. The provision of appropriate
  metadata is of extreme importance in establishing a virtual observatory,
  and the approach used can be adapted to facilitate the inclusion of
  any data, including non-solar data. We report on the capabilities of
  EGSO and discuss experience gained in creating the facility. We also
  discuss how EGSO has been working with other virtual observatories that
  support the solar, heliospheric and space plasma communities in order
  to try to achieve interoperability between the numerous data sets. We
  highlight what we consider are the most profitable ways of doing this.

Title: Using the Collaborative Sun-Earth Connector for integrating
    data systems
Authors: Hurlburt, N.; Freeland, S.; Slater, G.; Bentley, R.; Hill,
   F.; Bose, P.
Bibcode: 2005AGUSMSH43B..05H
Altcode:
  We demonstrate the coupling of disjoint data systems into virtual
  collaborative operations using the Collaborative Sun-Earth Connector
  (CoSEC). In addition to demonstrating possible interactions between
  Virtual observatories, we will present how individual missions and
  researchers can integrate their systems with space science services
  already incorporated into CoSEC. We present more advanced concepts of
  how to create collaborative data environments using upcoming solar
  missions as examples. This research has been supported through NASA
  contract NNH04CC00C.

Title: The User Interface of the European Grid of Solar Observations
Authors: Scholl, I. F.; Bentley, R. D.; Csillaghy, A.
Bibcode: 2005AGUSMSP51A..05S
Altcode:
  The European Grid of Solar Observations (EGSO) is a grid testbed
  funded by the European Commission's Fifth Framework Program under
  its Information Society Technologies (IST) thematic priority. This
  3-year project was designed to provide enhanced access to solar
  and related data around the world. The services provided by EGSO
  can be accessed through different interfaces. The main access is
  a Web-based Graphical User Interface (GUI) that allows the user to
  access the services offered by the grid in a common and integrated
  way. Also, an Application Programming Interface (API) is available
  in the SolarSoft package, that allows access to the services from IDL
  applications. Furthermore, various dedicated web interfaces allow to
  access individual catalogs built in the framework of this project,
  such as the Solar Event Catalog (SEC), the Solar feature Catalog (SFC),
  and the Unified Observing Catalog (UOC). In this paper we present the
  final version of the Grid, featuring the latest GUI, the new IDL API,
  as well as the access to the different catalogs and registries that
  help resolving complex queries and route them through the appropriate
  nodes of the Grid. The featured version of the GUI also provides users
  with a new function that helps them to search for instruments based
  only on some observational characteristics. In this final version, all
  major and recent solar data sets are now accessible from EGSO. EGSO
  is also closely coupled to the Collaborative Sun-Earth Connector
  (CoSEC), another virtual observatory-related project, from which it
  uses processing services. More information about EGSO can be found
  under http://www.egso.org/

Title: Filament Recognition and Image Cleaning on Meudon Hα
    Spectroheliograms
Authors: Fuller, Nicolas; Aboudarham, Jean; Bentley, R. D.
Bibcode: 2005SoPh..227...61F
Altcode:
  This paper presents the techniques developed for the automated detection
  of filaments on Meudon Hα spectroheliograms, and, by extension, on
  any full-disk Hα Sun observations. Some cleaning processes are first
  applied to the images to correct them from defects characteristic of the
  instrument. Indeed, these defects may lead to spurious detections. From
  the cleaned images, filament areas are then segmented using a region
  growing method which efficiently returns the full extent of these dark
  areas. The filaments are finally described by means of their pruned
  skeleton. This representation allows one to compare the automatically
  segmented filaments with those manually recorded for Meudon Synoptic
  Maps. The very good agreement observed on a representative set of
  images confirms that this method can effectively be used in the frame
  of the EGSO (European Grid of Solar Observations) project in order to
  produce a reliable catalog dedicated to solar features.

Title: Space weather and commercial airlines
Authors: Jones, J. B. L.; Bentley, R. D.; Hunter, R.; Iles, R. H. A.;
   Taylor, G. C.; Thomas, D. J.
Bibcode: 2005AdSpR..36.2258J
Altcode:
  Space weather phenomena can effect many areas of commercial airline
  operations including avionics, communications and GPS navigation
  systems. Of particular importance at present is the recently
  introduced EU legislation requiring the monitoring of aircrew
  radiation exposure, including any variations at aircraft altitudes
  due to solar activity. With the introduction of new ultra-long-haul
  “over-the-pole” routes, “more-electric” aircraft in the future,
  and the increasing use of satellites in the operation, the need for
  a better understanding of the space weather impacts on future airline
  operations becomes all the more compelling. This paper will present the
  various space weather effects, some provisional results of an ongoing
  3-year study to monitor cosmic radiation in aircraft, and conclude by
  summarising some of the identified key operational issues, which must
  be addressed, with the help of the science community, if the airlines
  want to benefit from the availability of space weather services.

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.
Bibcode: 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: User Access to the European Grid of Solar Observations
Authors: Scholl, I. F.; Bentley, R. D.; Csillaghy, A.
Bibcode: 2004AGUFMSH21B0416S
Altcode:
  The European Grid of Solar Observations (EGSO) is a grid testbed
  funded by the European Commission's Fifth Framework Programme under
  its Information Society Technologies (IST) thematic priority. The
  project started in 2002 and is designed to provide enhanced access
  to solar and related data around the world. One front-end of EGSO
  is a Graphical User Interface (GUI) that allows the user to access
  all the services offered by the grid from a common and integrated
  interface. Other front-ends are an IDL API and various dedicated web
  interfaces to access all the different catalogs built in the frame
  of this project like the Solar Event Catalog (SEC) the Solar feature
  Catalog (SFC) the Unified Observing Catalog (UOC). The GUI, as well
  as the API, provides also users with external processing services like
  those offered by the Collaborative Sun-Earth Connector (CoSEC), another
  virtual observatory-like project. In this paper we will present the EGSO
  front-ends with a special focus on the GUI. We will also demonstrate
  interactions between catalogs and the query system underlying the user
  interfaces in order to help the user when specifying complex scientific
  queries and eventually retrieving the corresponding solar data. More
  information about EGSO can be found under http://www.egso.org/

Title: Solving Science Use Cases that relate to the Sun and
    Heliosphere with EGSO
Authors: Bentley, R. D.; Scholl, I.; Csillaghy, A.; Aboudarham,
   J.; Antonucci, E.; Gurman, J. B.; Hill, F.; Pike, D.; Vial, J.;
   Zharkova, V.
Bibcode: 2004AGUFMSH21B0415B
Altcode:
  The European Grid of Solar Observations (EGSO) is a grid testbed
  funded by the European Commission's Fifth Framework Programme under
  its Information Society Technologies (IST) thematic priority. The
  project started in 2002 and is designed to provide enhanced access to
  solar and related data around the world. The EGSO grid is composed
  of two main components, Roles to set up the grid and, catalogs and
  registries to allow roles to answer users queries. Catalogs are made
  of lists of observations, events and features (a new service provided
  by EGSO). Registries are built from these catalogs and organized in
  order to enhance search capabilities. EGSO is working closely with
  other virtual observatory (VO) projects in the solar physics and
  related domains. This includes the US Virtual Solar Observatory (VSO)
  and the Collaborative Sun-Earth Connector (CoSEC). More recently we
  have been working with the Virtual Space Plasma Observatory (VSPO) and
  have contact with the Virtual Heliospheric Observatory (VHO). Through
  discussions with future missions, and within the new IAU Working
  Group on ``International Data Access'' (Solar and Heliospheric),
  the VOs are studying ways of ensuring interoperability from the
  ``sun to dirt''. This type of integrated access will be particularly
  important to missions such as STEREO and Living Witha Star. In this
  paper we will report the current status of EGSO, demonstrate how the
  catalogs and registries model serves within the user interface, and
  show how the user can retrieve solar and heliospheric data to match
  a scientific query. EGSO Release 4 is now being Beta-tested by users
  and anyone interested should view the Web page detailing all the EGSO
  capabilities under http://www.egso.org/demo

Title: Effect of solar energetic particle (SEP) events on the
radiation exposure levels to aircraft passengers and crew: Case
    study of 14 July 2000 SEP event
Authors: Iles, R. H. A.; Jones, J. B. L.; Taylor, G. C.; Blake, J. B.;
   Bentley, R. D.; Hunter, R.; Harra, L. K.; Coates, A. J.
Bibcode: 2004JGRA..10911103I
Altcode:
  We investigate the circumstances required for aircrew and passengers
  to experience an increased radiation exposure rate from a solar
  energetic particle (SEP) event occurring during a flight. The effects
  of the 14 July 2000 National Oceanic and Atmospheric Administration
  S3 class SEP event are examined using ground-based and satellite
  measurements together with coincident measurements made using a tissue
  equivalent proportional counter (TEPC) on board a Virgin Atlantic
  Airways flight from London Heathrow to Hong Kong. In this paper we
  present the first measurements made during a SEP event using a TEPC at
  flight altitudes. Our results indicate that there were no increased
  radiation levels detected during the flight due to the SEPs, but the
  measurements agreed well with the CARI-6 model calculations made using
  a heliocentric potential value derived immediately prior to the SEP
  event. In addition, a prolonged increase in the &gt;85 MeV particle
  flux is observed for up to 2 days after the SEP onset by the SAMPEX
  spacecraft at latitudes &gt;55°.

Title: The European grid of solar observations
Authors: Bentley, Robert D.; Csillaghy, Andre; Scholl, Isabelle
Bibcode: 2004SPIE.5493..170B
Altcode:
  The European Grid of Solar Observations (EGSO) is a Grid test-bed that
  will change the way users analyze solar data. One of the major hurdles
  in the analysis of solar data is finding what data are available and
  retrieving those required. EGSO is integrating the access to solar data
  by building a Grid including solar archives around the world. The Grid
  relies on metadata and tools for selecting, processing and retrieving
  distributed and heterogeneous solar data. EGSO is also creating a
  solar feature catalogue giving for the first time the ability to
  select solar data based on phenomena and events. In essence, EGSO is
  providing the fabric of a virtual observatory. Since the first release
  of EGSO in September 2003, members of the solar community have been
  involved in product testing. The constant testing and feedback allows
  us to assure the usability of the system. The capabilities of the
  latest release will be described, and the scientific problems that
  it addresses discussed. EGSO is funded under the IST (Information
  Society Technologies) thematic priority of the European Commission's
  Fifth Framework Programme (FP5) Ð it started in March 2002 and will
  last for three years. The EGSO Consortium comprises 11 institutes from
  Europe and the US and is led by the Mullard Space Science Laboratory
  of University College London. EGSO is collaborating with other groups
  in the US who are working on similar virtual observatory projects for
  solar and heliospheric data with the objective of providing integrated
  access to these data.

Title: Virtual Solar Inc.
Authors: Bentley, R. D.; Hill, F.; Hurlburt, N.
Bibcode: 2004ASPC..314..311B
Altcode: 2004adass..13..311B
  The need to develop new ways of accessing solar observations, coupled
  with rapidly increasing volumes of data and the desire to share
  data with other communities, has led to several projects intended
  to create virtual solar observatories. We outline the three main
  initiatives, EGSO, VSO and CoSEC, and describe how the the combined
  effort will result in a facility that will better match the needs of the
  community. Interaction with related communities are discussed, including
  similarities and differences with the IVOA and interoperability.

Title: TWiki: A Collaboration Platform for VO Projects
Authors: Leoni, M. C.; Dolensky, M.; Bentley, R.; Goodwin, T.;
   Linde, T.
Bibcode: 2004ASPC..314..307L
Altcode: 2004adass..13..307L
  Finding an easy way of sharing knowledge and experience in a
  geographically dispersed project team is not easy. The TWiki is a
  Web-based collaboration platform. It looks like a normal Internet web
  site, but everybody can change pages or add content by just using
  a browser. A revision control keeps track of changes. <P />Several
  Virtual Observatory projects use this type of web site to share info
  among project members and across projects. This is an experience report
  on the usage and maintenance of TWiki sites in Astronomy. <P />Even
  if at first it seems almost the opposite of how the Web and on-line
  communications "normally" work, it is intuitive and aspires to the
  Zen ideals known as Wabi-Sabi: "It finds beauty in the imperfect and
  ephemeral and constantly evolving".

Title: A Solar Data Model for Use in Virtual Observatories
Authors: Reardon, K. P.; Bentley, R. D.; Messerotti, M.; Giordano, S.
Bibcode: 2004AAS...204.7003R
Altcode: 2004BAAS...36Q.796R
  The creation of a virtual solar observatories relies heavily on the
  merging of the metadata describing different datasets into a common
  form so that it can be handled in a standard way for all associated
  resources. In order to bring together the varied data descriptions
  that already exist, it is necessary to have a common framework on
  which all the different datasets can be represented. The definition of
  this framework is done through a data model which attempts to provide
  a simplified but realistic description of the various entities that
  make up a data set or solar resource. <P />We present the solar data
  model which has been developed as part of the European Grid of Solar
  Observations (EGSO) project. This model attempts to include many of
  the different elements in the field of solar physics, including data
  producers, data sets, event lists, and data providers. This global
  picture can then be used to focus on the particular elements required
  for a specific implementation. We present the different aspects of
  the model and describe some systems in which portions of this model
  have been implemented.

Title: The European Grid of Solar Observations
Authors: Bentley, R. D.; Scholl, I.; Csillaghy, A.; Antonucci, E.;
   Zharkova, V. V.; Abourdarham, J.; Pike, C. D.; EGSO Team
Bibcode: 2004AAS...204.5206B
Altcode: 2004BAAS...36R.754B
  The European Grid of Solar Observations (EGSO) is a Grid test-bed funded
  by the European Commission that will change the way users analyze solar
  data. The project is tackling one of the major hurdles in the analysis
  of solar data - identifying what data are available and retrieving those
  that are needed. To do this, EGSO is creating new forms of metadata that
  will speed the search process and for the first time provide the ability
  to select data based on features,phenomena and events. <P />The project
  completed its second year in March 2004 and is now on Release 4 of the
  code. Since the first release in September 2003, members of the solar
  community have been involved in product testing. The constant testing
  and feedback allows us to assure the usability of the system. <P />We
  will describe the capabilities of the latest release and discuss the
  scientific problems that it is currently able to address.

Title: Integrated Access to Solar Data using EGSO
Authors: Scholl, I.; Bentley, R.; Csillaghy, A.; EGSO Team
Bibcode: 2004AAS...204.7005S
Altcode: 2004BAAS...36..796S
  The European Grid of Solar Observations (EGSO) is a virtual observatory
  based on Grid technology funded under the IST (Information Society
  Technologies) thematic priority of the European Commission's Fifth
  Framework Programme (FP5). <P />EGSO allows the user to use metadata
  catalogues to select solar data based on a number of criteria, including
  a search based on events, features or phenomena. Since the first release
  of EGSO in September 2003, members of the solar community have been
  involved in product testing. The constant testing and feedback allows
  us to continue to improve the quality and usability of the system. The
  capabilities of the latest release (R4) will be demonstrated and
  the scientific problems that it addresses discussed. <P />EGSO is
  collaborating closely with groups in the US who are working on similar
  virtual observatory projects for the solar, solar-terrestrial and
  heliospheric communities with the objective of providing integrated
  access to these data. In particular, strong synergies between the EGSO
  and CoSEC projects are producing innovative ways of accessing the data
  that will be deployed in both projects.

Title: IAU Working Group on International Data Access for Solar and
    Heliospheric data
Authors: Bentley, R. D.; Hill, F.; Hurlburt, N.; Roberts, A.
Bibcode: 2004AAS...204.5207B
Altcode: 2004BAAS...36S.754B
  Division II (Sun and Heliosphere) of the IAU has initiated a Working
  Group to study the archiving, retrieval and distribution of solar and
  heliospheric data. The goal of the Working Group is to facilitate the
  use of available solar and heliospheric data that are archived in
  a large number of computers scattered all over the world. <P />The
  intent of the Working Group is to help coordinate the existing and
  growing data exchange through the Internet and work with the virtual
  observatory initiatives to propose guidelines for exchange at an
  international level and encourage participation in the projects. <P
  />The Working Group is working with the virtual observatory initiatives
  to ensure that they develop standards and employ techniques that are
  acceptable to the worldwide solar and heliospheric communities and
  to encourage interoperability between the projects. The EGSO, VSO,
  CoSEC and VSPO projects are all part of the Working Group and would
  also like to encourage the communities to help develop standards and
  participate in the virtual observatory projects. <P />The aims of and
  objectives the Working Group will be discussed and feedback from the
  audience is encouraged.

Title: Tracking of Solar Active Regions and Search for Classification
    parameters
Authors: Benkhalil, A.; Zharkova, V.; Bentley, R.; Zharkov, S.;
   Ipson, S.
Bibcode: 2004cosp...35.3115B
Altcode: 2004cosp.meet.3115B
  This paper presents the application of Solar Feature Catalogue (SFC)
  created with an automated technique for active region detection from
  SOHO/MDI, SOHO/EIT and Hα images from Meudon. The two active regions
  (NOAA 484 and 486) producing many flares in October and November '03
  were tracked during their lifetime on a solar disk in Hα and Fe XII,
  195 Å wavelengths. These regions produced a large number of flares with
  different significance including a few X-class flares. We investigate
  their morphology and evaluation leading to a flare production and
  compare these with the magnetic field changes before and during a
  flare. In SFC each region is characterized by a number of physical and
  photometric properties, which are stored in the database. These include:
  the center of gravity in pixel and heliographic coordinates; minimum,
  maximum and mean intensity within the active region; area in square
  degrees and dimensions in pixels; contrast ratios; and a chain-code
  representation of the active region boundary. Based on a comparison of
  the active region parameters selected from the SFC with the magnetic
  field configuration and strength we try to select the key parameters
  defining a region activity in flare production that can be used for
  a preliminary active region classification.

Title: Space Weather affects on Air Transportation
Authors: Jones, J. B. L.; Bentley, R. D.; Dyer, C.; Shaw, A.
Bibcode: 2004cosp...35.3522J
Altcode: 2004cosp.meet.3522J
  In Europe, legislation requires the airline industry to monitor
  the occupational exposure of aircrew to cosmic radiation. However,
  there are other significant impacts of space weather phenomena on the
  technological systems used for day-to-day operations which need to be
  considered by the airlines. These were highlighted by the disruption
  caused to the industry by the period of significant solar activity
  in late October and early November 2003. Next generation aircraft
  will utilize increasingly complex avionics as well as expanding the
  performance envelopes. These and future generation platforms will
  require the development of a new air-space management infrastructure
  with improved position accuracy (for route navigation and landing
  in bad weather) and reduced separation minima in order to cope with
  the expected growth in air travel. Similarly, greater reliance will
  be placed upon satellites for command, control, communication and
  information (C3I) of the operation. However, to maximize effectiveness
  of this globally interoperable C3I and ensure seamless fusion of all
  components for a safe operation will require a greater understanding
  of the space weather affects, their risks with increasing technology,
  and the inclusion of space weather information into the operation. This
  paper will review space weather effects on air transport and the
  increasing risks for future operations cause by them. We will examine
  how well the effects can be predicted, some of the tools that can be
  used and the practicalities of using such predictions in an operational
  scenario. Initial results from the SOARS ESA Space Weather Pilot
  Project will also be discussed,

Title: Statistical analysis of long-term variations of the sunspot
    and umbral magnetic field
Authors: Zharkov, S. I.; Zharkova, V. V.; Bentley, R. D.
Bibcode: 2004cosp...35.3113Z
Altcode: 2004cosp.meet.3113Z
  Using the EGSO Solar Feature Catalogue for sunspots created from the
  SOHO/MDI white light and magnetogram data for the period of 1995-2002
  with the developed automated detection technique. The detected sunspots
  overlaid with the SOHO/MDI magnetograms obtained for the corresponding
  time periods. The magnetogram data is used for sunspot separation into
  the groups corresponding to the active region and adding a positive
  or negative polarity tag. The results are unified under the synoptic
  maps of sunspots and magnetic structures. We present short term (per
  month) and long-term (years) statistical analysis of magnetic fluxes
  from whole sunspots and umbral areas, their locations and temporal
  variations during the selected period. The comparison revealed a strong
  north-south asymmetry in the identified sunspot and umbral magnetic
  fluxes, which varies with the solar activity cycle. This research is
  a part of the European Grid of Solar Observations (EGSO) project.

Title: The AstroGrid Pilot Programme
Authors: Mann, R. G.; Davenhall, A. C.; Page, C. G.; Watson, M. G.;
   Richards, A. M. S.; Garrington, S. T.; Holloway, A. J.; Bentley,
   R. D.; Pike, C. D.; Perry, C. H.; Stamper, R.
Bibcode: 2004tivo.conf..147M
Altcode:
  We describe the AstroGrid Pilot Programme, a set of testbeds conducted
  during AstroGrid's one-year Phase A study, and intended to complement
  the science requirements analysis and technology evaluations comprising
  the remainder of the Phase A programme. We selected a pilot to address
  an issue of particular relevance to each of AstroGrid's five broad
  scientific areas, to allow empirical study of many aspects of the
  general database federation problem and to engage, from the outset,
  all parts of our user community. The lessons learnt during the course
  of the Pilot Programme will help define the direction of AstroGrid's
  Phase B implementation.

Title: Integrated Access to Solar Data using EGSO
Authors: Bentley, R. D.; Csillaghy, A.; Scholl, I.; Vial, J. -C.;
   Aboudarham, J.; Antonucci, E.; Zharkova, V. V.; Pike, C. D.
Bibcode: 2004cosp...35.3935B
Altcode: 2004cosp.meet.3935B
  The European Grid of Solar Observations (EGSO) is a virtual observatory
  based on Grid technology that will change the way users analyze solar
  data. EGSO is funded under the IST (Information Society Technologies)
  thematic priority of the European Commission's Fifth Framework Programme
  (FP5). It started in March 2002 and will last for 3 years. The EGSO
  Consortium comprises eleven groups from five countries in Europe
  and the US, and is led by the Mullard Space Science Laboratory
  of University College London. The project aims to overcome one of
  the major hurdles in the analysis of solar data - finding what data
  are available and retrieving those that are needed. EGSO is creating
  layers of metadata catalogues that will for the first time provide the
  ability to select solar data based on phenomena and events. It is also
  integrating access to solar data by building a Grid including solar
  archives around the world. This combination of metadata and tools for
  selecting, processing and retrieving distributed and heterogeneous
  solar data, will radically change the way that data are distributed
  and analyzed. EGSO is collaborating closely with groups in the US who
  are working on similar virtual observatory projects for the solar,
  solar-terrestrial and heliospheric communities with the objective
  of providing integrated access to these data. In particular, strong
  synergies between the EGSO and CoSEC projects are producing innovative
  ways of accessing the data that will be deployed in both projects. Since
  the first release of EGSO in September 2003, members of the solar
  community have been involved in product testing. The constant testing
  and feedback allows us to continue to improve the quality and usability
  of the system. The capabilities of the latest release (R4) will be
  described, and the scientific problems that it addresses discussed.

Title: Intelligent approach to the data analysis with the Solar
    Feature Catalogues
Authors: Zharkova, V. V.; Aboudarham, J.; Ipson, S. S.; Bentley,
   R. D.; Zharkov, S. I.; Benkhalil, A. K.; Fuller, N.
Bibcode: 2004cosp...35.3488Z
Altcode: 2004cosp.meet.3488Z
  This paper presents searchable Solar Feature Catalogues developed
  for the European Grid of Solar Observations using various image
  processing and pattern recognition techniques. The techniques were
  applied on solar images for automated detection of sunspots, active
  regions, filaments and magnetic field on the Ca II K1, Ca II K3
  and H<SUB>α</SUB> solar images from the Meudon Observatory and the
  SOHO/MDI white light images and magnetograms. Using the recognised
  parameters a structured database of the solar feature catalogues was
  built on a mysql server for every feature and used for tracking of
  a few active regions and associated with them magnetic field changes
  produced many solar flares in October-November '03. We try to define
  the key parameters for active region activity and relate them to the
  parameters recognised with SFC for the future activity forecast. Some
  samples of statistical analysis of sunspot areas and locations are
  also presented and used for classification. The work is a part of the
  project European Grid of Solar Observations. .

Title: Intelligent approach to the data analysis with the Solar
    Feature Catalogues
Authors: Zharkova, V. V.; Aboudarham, J.; Ipson, S. S.; Bentley,
   R. D.; Zharkov, S. I.; Benkhalil, A. K.; Fuller, N.
Bibcode: 2004cosp...35.3491Z
Altcode: 2004cosp.meet.3491Z
  This paper presents searchable Solar Feature Catalogues developed
  for the European Grid of Solar Observations using various image
  processing and pattern recognition techniques. The techniques were
  applied on solar images for automated detection of sunspots, active
  regions, filaments and magnetic field on the Ca II K1, Ca II K3 and
  H<SUB>α</SUB> solar images from the Meudon Observatory and the SOHO/MDI
  white light images and magnetograms. Using the recognised parameters
  a structured database of the solar feature catalogues was built on
  a mysql server for every feature and used for tracking of the active
  regions 484 and 486 and associated with them magnetic field changes
  produced many solar flares in October-November '03. We try to define
  the key parameters for active region activity and relate them to the
  parameters recognised with SFC for the future activity forecast. Some
  samples of statistical analysis of sunspot areas and locations are
  also presented and used for classification. The work is a part of the
  project European Grid of Solar Observations.

Title: Tracking of solar active regions and search for classification
    parameters
Authors: Benkhalil, A.; Zharkova, V.; Bentley, R.; Zharkov, S.;
   Ipson, S.
Bibcode: 2004cosp...35.3125B
Altcode: 2004cosp.meet.3125B
  This paper presents the application of Solar Feature Catalogue (SFC)
  created with an automated technique for active region detection from
  SOHO/MDI, SOHO/EIT and Hα images from Meudon. The two active regions
  (NOAA 484 and 486) producing many flares in October and November '03
  were tracked during their lifetime on a solar disk in Hα and Fe XII,
  195 Å wavelengths. These regions produced a large number of flares with
  different significance including a few X-class flares. We investigate
  their morphology and evaluation leading to a flare production and
  compare these with the magnetic field changes before and during a
  flare. In SFC each region is characterized by a number of physical and
  photometric properties, which are stored in the database. These include:
  the center of gravity in pixel and heliographic coordinates; minimum,
  maximum and mean intensity within the active region; area in square
  degrees and dimensions in pixels; contrast ratios; and a chain-code
  representation of the active region boundary. Based on a comparison of
  the active region parameters selected from the SFC with the magnetic
  field configuration and strength we try to select the key parameters
  defining a region activity in flare production that can be used for
  a preliminary active region classification.

Title: A full-disk image standardisation of the synoptic solar
    observations at the Meudon Observatory
Authors: Zharkova, V. V.; Ipson, S. S.; Zharkov, S. I.; Benkhalil,
   A.; Aboudarham, J.; Bentley, R. D.
Bibcode: 2003SoPh..214...89Z
Altcode:
  Robust techniques are developed to put the Hα and Ca K line full-disk
  images taken at the Meudon Observatory into a standardised form of a
  `virtual solar image'. The techniques include limb fitting, removal
  of geometrical distortion, centre position and size standardisation
  and intensity normalisation. The limb fitting starts with an initial
  estimate of the solar centre using raw 12-bit image data and then
  applies a Canny edge-detection routine. Candidate edge points for the
  limb are selected using a histogram based method and the chosen points
  fitted to a quadratic function by minimising the algebraic distance
  using SVD. The five parameters of the ellipse fitting the limb are
  extracted from the quadratic function. These parameters are used to
  define an affine transformation that transforms the image shape into a
  circle. Transformed images are generated using the nearest neighbour,
  bilinear or bicubic interpolation. Intensity renormalisation is also
  required because of a limb darkening and other non-radial intensity
  variations. It is achieved by fitting a background function in polar
  coordinates to a set of sample points having the median intensities
  and by standardising the average brightness. Representative examples
  of intermediate and final processed results are presented in addition
  to the algorithms developed. The research was done for the European
  Grid of Solar Observations (EGSO) project.

Title: Solar Feature Catalogue in the European Grid of Solar
    Observations
Authors: Zharkova, V. V.; Ipson, S. S.; Bentley, R. D.; Aboudarham,
   J.; Zharkov, S.; Benkhalil, A.; EGSO Team
Bibcode: 2003SPD....34.0205Z
Altcode: 2003BAAS...35..807Z
  The first results in automated recognition of 4 different solar features
  (sunspots, active regions, filaments, magnetic field neutral lines)
  are presented. The problems associated with a digital image cleaning,
  pattern recognition techniques applicable to different types of features
  and their implementation in the Solar Feature Catalogues (SFCs) are
  discussed. The preliminary results of a systematic investigation of
  the selected features chosen from the SFCs and their correlations
  with magnetic structures are presented. The research is done for the
  European Grid of Solar Observations funded by the European Commission.

Title: EGSO - Current Status and Expectations
Authors: Bentley, R. D.; EGSO 0
Bibcode: 2003SPD....34.0204B
Altcode: 2003BAAS...35..807B
  EGSO, the European Grid of Solar Observations, is developing a data Grid
  to provide enhanced access to solar data from around the globe. The
  project, which is funded by the European Commission, is just over a
  year old and it recently passed its first review. A working version of
  the architectural design was recently completed and detailed work has
  now started in earnest. <P />We will present details of the design,
  how it will be implemented and the timescales for different part of
  the project. Examples of services and interfaces already available
  will be shown. <P />EGSO is working closely with the US Virtual Solar
  Observatory (US-VSO) and the Sun-Earth Connector (CoSEC) and we are
  trying to the projects compliment each other - a working group to
  ensure this was recently formed. <P />For more details on EGSO see
  our web site or contact the author.

Title: First Steps to Solar Feature Catalogues
Authors: Zharkova, Valentina V.; Bentley, Robert D.; Ipson, Stanley S.;
   Zharkov, Sergey I.; Benkhalil, Ali; Aboudarham, Jean; Fuller, Nicolas
Bibcode: 2003IAUJD...7E..14Z
Altcode:
  The first results are presented for automated recognition of four
  different features: sunspots active regions filaments and magnetic
  field and their presentation in the feature catalogues. We discuss
  problems with digital images standardisation and pattern recognition
  techniques for different types of wavelengths. Possible application of
  the feature catalogues for the Space Weather project is discussed. The
  research was funded by the European Grid of Solar Observation project
  IST 2001 32409 funded by the European Commission.

Title: EGSO - the European Grid of Solar Observations
Authors: Bentley, Robert D.; EGSO Consortium
Bibcode: 2002ESASP.506..923B
Altcode: 2002ESPM...10..923B; 2002svco.conf..923B
  The European Grid of Solar Obervations (EGSO) is a Grid testbed funded
  by the European Commission under the Information Society Technologies
  (IST) thematic priority of the Fifth Framework Programme (FP5). EGSO
  will provide the tools and infrastructure needed to create a data grid
  that will form the fabric of a virtual solar observatory. EGSO started
  in March 2002 and will last for 36 months. The project involves eleven
  groups from ten institutions located in five countries in Europe and
  the US and is led by University College London. The EGSO Consortium
  is in discussion with other groups interested in creating a virtual
  observatory with the aim of finding a solution that is universally
  acceptable.

Title: EGSO in need for a global schema
Authors: Hill, Frank; Csillaghy, Andre; Bentley, Robert D.; Aboudarham,
   Jean; Antonucci, Ester; Finkelstein, Anthony; Ciminiera, Luigi;
   Gurman, Joseph B.; Scholl, Isabelle; Pike, Dave; Zharkova, Valentin
Bibcode: 2002SPIE.4846...35H
Altcode:
  The European Grid of Solar Observations (EGSO) is a project to develop
  a virtual observatory for the solar physics community. Like in all
  such projects, a vital component is a schema that adequately describes
  the data in the distributed data sets. Here, we discuss the schema in
  general terms, and present a draft example of a portion of a possible
  XML schema.

Title: On a possible cause of discrepancy between Yohkoh and SMM
    calcium abundance determinations in flares
Authors: Sylwester, J.; Kepa, A.; Bentley, R. D.
Bibcode: 2002AdSpR..30..105S
Altcode:
  We have investigated problems concerning the discrepancy between
  estimates of absolute calcium abundances (A <SUB>Ca</SUB>) in solar
  flares as derived from soft X-ray high resolution spectra as obtained
  from Yohkoh and Solar Maximum Mission ( SMM) Bragg spectrometers. The
  analysis of these spectra allows for determination of absolute calcium
  abundance since both Ca XIX resonance line and neighbouring continuum
  are reliably measured in these experiments. The abundance determinations
  are possible by means of fitting the synthetic spectra to the observed
  ones. In previous work, we attributed part (around 50%) of the observed
  disagreement to a possible instrumental problem in Yohkoh. In the
  present research, we consider in more details possible causes of
  the other part of the discrepancy. We first investigate whether the
  estimates of (A <SUB>Ca</SUB>) depend substantially on the extension of
  the observed short wavelength wing of the Ca XIX resonance line. This
  problem is important in the case of the analysis of Yohkoh spectra,
  since the extension of the spectrum towards the short wavelengths
  depends on the position of the flare along North—South direction
  on the Sun. After verifying the robustness of results of the spectral
  fitting technique, we have considered possible physical scenario which
  may cause the observed discrepancy. The hypothesis tested was that
  the Ca abundance in flares is correlated with brightness in the source
  — namely that it is a few times higher in the centre of the source
  (flaring kernel) than outside. We have found that postulated model may
  account for a part of the noted discrepancy as the SMM spectrometer
  has been equipped with the 6 × 6 arcmin collimator and no collimator
  has been used on Yohkoh.

Title: The European Grid of Solar Observations (EGSO)
Authors: Bentley, R. D.; EGSO Team
Bibcode: 2002AAS...200.5804B
Altcode: 2002BAAS...34..740B
  A major hurdles in the analysis of solar data is finding what data
  are available and retrieving those that are needed. Planned space-
  and ground-based instruments will produce huge volumes of data and
  even taking into account the continuous technical advances, it is
  clear that a new approach is needed to the way we use these data. The
  European Grid of Solar Observations (EGSO) is a Grid test-bed that will
  change the way users analyze solar data. EGSO will federate solar data
  archives across Europe and beyond, and will create the tools to select,
  process and retrieve distributed and heterogeneous solar data. It will
  provide mechanisms to produce standardized observing catalogues for
  space and ground-based observations, and the tools to create solar
  feature catalogues that will facilitate the selection of solar data
  based on features, events and phenomena. In essence, EGSO will provide
  the fabric of a virtual observatory. EGSO is funded under the IST
  (Information Society Technologies) thematic programme of European
  Commission's Fifth Framework Programme (FP5). The project started in
  March 2002 and will last for 3 years. The EGSO consortium comprises
  10 institutes from Europe and the US, and is led by the Mullard Space
  Science Laboratory (MSSL) of University College London (UCL). EGSO
  plans to work closely with groups funded under NASA's Virtual Solar
  Observatory (VSO) initiative, and with the team at Lockheed-Martin
  who are doing similar work within the ILWS programme.

Title: EGSO - the next step in data analysis
Authors: Bentley, Robert D.
Bibcode: 2002ESASP.477..603B
Altcode: 2002scsw.conf..603B
  In April 2001, a proposal to create a grid of solar data archives
  was submitted to the European Commission under the Information
  Society Technologies (IST) program. The European Grid of Solar
  Observations (EGSO) will provide the tools and infrastructure needed
  to create the data grid that will form the fabric of a virtual
  solar observatory. Every attempt will be made to ensure that EGSO is
  universally acceptable. The EGSO proposal has been positively evaluated
  and the project has been selected for negotiation. If successful,
  the project will start in early 2002.

Title: Monitoring cosmic radiation on aircraft
Authors: Bentley, Robert D.; Iles, R. H. A.; Jones, J. B. L.; Hunter,
   R.; Taylor, G. C.; Thomas, D. J.
Bibcode: 2002ESASP.477..535B
Altcode: 2002scsw.conf..535B
  The Earth is constantly bombarded by cosmic radiation that can be either
  galactic or solar in origin. At aircraft altitudes, the radiation levels
  are much higher than at sea level and recent European legislation has
  classified aircrew as radiation workers. University College London is
  working with Virgin Atlantic Airways on a 3 year project to monitor
  the levels of cosmic radiation on long-haul flights. The study will
  determine whether models currently used to predict radiation exposure
  of aircrew are adequate. It will also try to determine whether solar
  flare activity can cause significant enhancement to the predicted doses.

Title: Early results from RESIK and Diogeness soft X-ray spectrometers
    aboard Coronas-F satellite
Authors: Sylwester, Janusz; Gaicki, Ireneusz; Kordylewski, Zbigniew;
   Kowalinski, Miroslaw; Nowak, Stanislaw; Plocieniak, Stefan; Trzebinski,
   Witold; Bentley, Robert D.; Whyndham, Matt; Lang, Jim; Brown, Charles;
   Farnik, Frantisek; Oraevsky, Victor N.; Stepanov, Anatolyi; Lisin,
   Dimitry
Bibcode: 2002ESASP.477..597S
Altcode: 2002scsw.conf..597S
  We present examples of early, unreduced results obtained from
  the instrument package dedicated for spectroscopic studies of
  coronal flaring plasma composition. The package consists of two
  Bragg spectrometers, RESIK and Diogeness. These instruments have
  been launched aboard the Russian Coronas-F solar observatory on 31
  July 2001. The data being received from these two spectrometers allow
  for determining the absolute abundances of several important elements
  including that of low and high first ionization potential (FIP). Based
  on the data which have been (and hopefully will be) obtained, we will
  investigate fast temporal variations (~1 min) of the plasma composition
  in flares and hotter active regions. The analysis of spectra obtained
  will certainly allow for spectroscopic studies of several, so-called
  "triplet" lines forming in He-like, highly ionized plasma since the
  spectra received are apparently of unprecedented quality. The Coronas-F
  Mission is expected to be supported for at least two years.

Title: Space weather effects and commerical airlines
Authors: Jones, J.; Bentley, R.; Hunter, R.; Taylor, G.; Thomas, D.
Bibcode: 2002cosp...34E3042J
Altcode: 2002cosp.meetE3042J
  Space Weather (SW) phenomena can effect many areas of commercial
  airline operations including avionics, communications and GPS
  navigation systems. Of particular importance at present is the recently
  introduced EU legislation requiring the monitoring of aircrew radiation
  exposure, including any variations at aircraft altitudes due to solar
  activity. The Mullard Space Science Laboratory is collaborating with
  Virgin Atlantic Airways, the Civil Aviation Authority and the National
  Physical Laboratory on a 3- year project to monitor the levels of
  cosmic radiation on long-haul flights. The study will determine
  whether computer models currently used to predict radiation exposure
  of aircrew are adequate. It also aims to determine whether solar
  or geomagnetic activity can cause significant modifications to the
  doses. This presentation will begin by showing some of the preliminary
  results obtained so far. As an example, we present a comparison of
  flight doses measured following the 14t h July 2000 X - class flare
  that was accompanied by a major Solar Particle Event (SPE). The
  results highlight the importance of a range of external factors
  that can strongly influence how SPEs may effect the measured dose at
  aircraft altitudes. At present, any SPE contributions in the airlines'
  dose records can only be poorly estimated retrospectively. Ideally,
  it would be better to try to avoid operating during these possibly
  significant radiation - enhancing events by utilising SW information
  (alerts, warnings, etc.). However, doing so poses many difficult
  operational problems for such a heavily regulated international
  industry, in terms of safety, security and procedures. Therefore,
  the use of timely SW information, which is still very unreliable, in
  a similar manner to terrestrial weather will require agreement from
  the International Civil Aviation Organisation (ICAO) and International
  Air Transport Association (IATA) to Air Traffic Control and Aviation
  Regulatory Authority's. This presentation will, therefore, conclude by
  summarising some of the identified key issues, which must be addressed,
  with the help of the science community, if the airlines want to benefit
  from the availability of Space Weather Services.

Title: The European Grid of Solar Observations (EGSO)
Authors: Bentley, R. D.
Bibcode: 2001AGUFMSH31B0713B
Altcode:
  Access to solar data is becoming an increasing problem. Although
  the Internet has made it much easier to share data, the volume and
  complexity of the data are increasing rapidly, and it is often difficult
  to identify datasets of interest, and then locate and retrieve them. In
  April 2001, a proposal to create a Grid of solar data archives was
  submitted to the European Commission under the Information Society
  Technologies (IST) program. The European Grid of Solar Observations
  (EGSO) will provide the tools and infrastructure needed to create the
  data grid that will form the fabric of a virtual solar observatory. EGSO
  will allow a user to identify solar observations covering a given
  time interval, active region, or type of feature; it will locate
  the selected observation and then return them after any necessary
  pre-processing; it will also provide the facility of analyze large
  volumes of data at the data source. The EGSO consortium comprises 10
  groups in Europe and the US, including experts in both solar data and
  IT. The project has been positively evaluated and has been selected
  for negotiations. Inputs from the solar community are now needed in
  order to formulate the details of the project.

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

Title: SolarSoft
Authors: Freeland, S.; Bentley, R.
Bibcode: 2000eaa..bookE3390F
Altcode:
  The SolarSoft system (SSW) is a set of integrated software libraries,
  databases, and system utilities which provide a common programming
  and data analysis environment for solar physics. The SolarSoft
  environment provides a consistent look and feel at widely distributed
  co-investigator institutions to facilitate data exchange and to
  stimulate coordinated analysis. Commonalities and overlap in sola...

Title: Magnetic Activity Associated With Radio Noise Storms
Authors: Bentley, R. D.; Klein, K. -L.; van Driel-Gesztelyi, L.;
   Démoulin, P.; Trottet, G.; Tassetto, P.; Marty, G.
Bibcode: 2000SoPh..193..227B
Altcode:
  As it crossed the solar disk in May and June 1998, AR 8227 was tracked
  by TRACE, Yohkoh, SOHO, and many ground-based observatories. We have
  studied how the evolution of the magnetic field resulted in changes in
  activity in the corona. In particular, we examine how the evolving field
  may have led to the acceleration of electrons which emit noise storms
  observed by the Nançay Radio Heliograph between 30 May and 1 June
  1998, in the absence of any flare. The magnetic changes were related
  to moving magnetic features (MMFs) in the vicinity of the leading
  spot and are related to the decay of this spot. Within the limits of
  the instrumental capabilities, the location in time and space of the
  radio emissions followed the changes observed in the photospheric
  magnetograms. We have extrapolated the photospheric magnetic field
  with a linear force-free approximation and find that the active region
  magnetic field was very close to being potential. These computations
  show a complex magnetic topology associated to the MMFs. The observed
  photospheric evolution is expected to drive magnetic reconnection in
  such complex magnetic topology. We therefore propose that the MMFs
  are at the origin of the observed metric noise-storms.

Title: Influence of Yohkoh BCS Instrumental Shape on Results of
    Spectral Fitting in Vicinity of Ca XIX Lines
Authors: Kepa, A.; Sylwester, J.; Bentley, R. D.
Bibcode: 1999ESASP.448..835K
Altcode: 1999ESPM....9..835K; 1999mfsp.conf..835K
  No abstract at ADS

Title: Microwave, Soft and Hard X-Ray Observations of Solar Flares -
    a Self-Consistent Model of the Flare Site
Authors: Chiuderi Drago, F.; Alissandrakis, C. E.; Bentley, R. D.;
   Philips, A. T.
Bibcode: 1998SoPh..182..459C
Altcode:
  High-resolution microwave observations of several flares performed
  with the Westerbork Synthesis Radio Telescope (WRST) on 3 and 4 July
  1993 are compared with Yohkoh observations in the soft and hard X-ray
  domain. Only for one flare, among the six analyzed, was the hard
  X-ray spectrum between 20 and 200 keV available from the Wide Bragg
  Spectrometer, supplying the energy spectrum of non-thermal particles
  responsible for this radiation and for the radio emission. A complete
  model of this flare is derived which accounts for all available
  observations in the X-ray and radio wavelengths.

Title: Detailed Evidence for Flare-to-Flare Variations of the Coronal
    Calcium Abundance
Authors: Sylwester, J.; Lemen, J. R.; Bentley, R. D.; Fludra, A.;
   Zolcinski, M. -C.
Bibcode: 1998ApJ...501..397S
Altcode:
  The analysis of X-ray solar flare spectra obtained by the Bent
  Crystal Spectrometer on board the Solar Maximum Mission satellite is
  presented. The ratio of the Ca XIX resonance line intensity to the
  nearby continuum is used to measure the calcium abundance relative to
  hydrogen (A<SUB>Ca</SUB>). A description of the spectroscopic method
  of determining the absolute calcium abundance is given. Possible
  instrumental and solar effects that might influence the abundance
  estimates are evaluated. Over 5000 spectra from more than 100 flares are
  analyzed. We find a flare-to-flare variation for A<SUB>Ca</SUB> that is
  not correlated with flare size, Hα importance, or with several other
  flare characteristics. For flares observed from two active regions, the
  observed value of A<SUB>Ca</SUB> increases as a function of time. The
  average for all flares is &lt;A<SUB>Ca</SUB>&gt; = (5.77 +/- 1.41) ×
  10<SUP>-6</SUP>. A discussion of investigated correlations of derived
  A<SUB>Ca</SUB> values with several flare characteristics is presented.

Title: What YOHKOH has Discovered about Active Regions
Authors: Bentley, R. D.
Bibcode: 1998ASPC..155..176B
Altcode: 1998sasp.conf..176B
  No abstract at ADS

Title: Joint Observations and an Active Region with SOHO and YOHKOH
Authors: Bentley, R. D.
Bibcode: 1998ASSL..229..251B
Altcode: 1998opaf.conf..251B
  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.
Bibcode: 1998PAICz..88...91F
Altcode:
  No abstract at ADS

Title: YOHKOH Bragg Crystal Spectrometer Light Curves for S XV
    (5.0163 - 5.1143 Angstroms)
Authors: Mariska, John T.; Bentley, R. D.; Pike, C. D.
Bibcode: 1997STIN...9838248M
Altcode:
  This memorandum report summarizes the data produced during the sixth
  year of operation by the Bragg Crystal Spectrometer (BCS) on the Yohkoh
  spacecraft. Each page shows the total count rate in the S XV channel
  of the BCS for a single day. This channel nominally observes the Sun
  in the wavelength range from 5.0163 - 5.1143 Angstroms. These plots
  are useful for identifying flare data for further analysis and for
  determining the data file name and tape number that contains the data.

Title: The Whole Sun Catalogue
Authors: Sanchez Duarte, L.; Fleck, B.; Bentley, R.
Bibcode: 1997ASPC..118..382S
Altcode: 1997fasp.conf..382S
  To maximize the scientific outcome of the wealth of solar observations
  available, it would be extremely useful to have a complete, central
  catalogue giving some basic information such as `where, when, what'
  about all solar observations made. This paper presents a proposal
  for such a catalogue based on the infrastructure developed for the
  SOHO Archive, but being independent of it. Our goal is to refine this
  proposal with the help of the JOSO group and to implement it by 1997.

Title: Diagnostics of Energy Release in the X-Ray Corona
Authors: Bentley, Robert D.
Bibcode: 1997LNP...483....3B
Altcode: 1997cprs.conf....3B
  Energy is released in the corona in many different forms. In this
  paper we discuss phenomena that are observed in X-rays in flares
  and sub-flares. Recent results of X-ray bright-points, transient
  brightenings and jets are reviewed, and diagnostics that result from
  bulk plasma motions are discussed. Finally, three events are examined
  in detail and the implications of the observation discussed in relation
  to flare models.

Title: Calcium abundance measurements using the Yohkoh BCS
Authors: Bentley, R. D.; Sylwester, J.; Lemen, J. R.
Bibcode: 1997AdSpR..20.2275B
Altcode:
  Soft X-ray observations by SMM and other spacecraft have shown
  that the abundance of certain elements in solar corona varies from
  flare to flare. In this study, observations made by the Yohkoh Bragg
  Crystal Spectrometer (BCS) in helium-like Ca XIX have been analysed,
  and Ca abundance determined for 177 flares observed during the first
  four years of the mission (1991-1995). The average abundance of Ca
  relative to H for all flares is &lt; A_Ca &gt; = (3.64 +/- 0.39) x
  10^-6. As with an earlier study of SMM data, the abundance is found to
  be enhanced compared to the photosphere ((2.24 +/- 0.10) x 10^-6), and
  with only minor variation from flare to flare. However, the absolute
  value and range of values determined by this study is smaller than in
  the previous study; these differences are discussed.

Title: Hard and Soft X-Ray Observations of Solar Limb Flares
Authors: Mariska, John T.; Sakao, T.; Bentley, R. D.
Bibcode: 1996ApJ...459..815M
Altcode:
  Using observations from the Yohkoh Bragg Crystal Spectrometer, hard
  X-ray telescope, and soft X-ray telescope, we have examined eight limb
  flares. Four of the flares have the footpoints occulted by the solar
  limb. We find that the occulted flares generally have softer hard
  X-ray spectra and smaller peak values of the nonthermal broadening
  velocity than nonocculted flares. All other physical parameters show
  no differences between occulted flares and nonocculted flares. The
  hard X-ray spectra support a model in which the footpoint emission
  is due to thick-target sources, while the looptop emission is due to
  thin-target sources. High spectral resolution hard X-ray observations
  should thus show a break in the hard X-ray spectrum of the looptop
  source. We can find no obvious explanation for the differences in
  nonthermal broadening velocity.

Title: Timing of the soft X-ray blue-wing and the hard X-ray burst
    from observations by YOHKOH
Authors: Bentley, R. D.; Doschek, G. A.; Mariska, J. T.
Bibcode: 1996AdSpR..17d..55B
Altcode: 1996AdSpR..17...55B
  A knowledge of the relative timing of the hard X-ray burst and emission
  in soft X-rays is helpful in deciding between a number of theoretical
  models that describe the mechanism of a solar flare. Here we continue
  a study of this relationship using observations from the Yohkoh Bragg
  Crystal Spectrometer and Hard X-ray Telescope, together with supporting
  observations from the CGRO Batse experiment. The enhanced capabilities
  of the instruments onboard Yohkoh have made it possible to study the
  problem in a way that was not previously possible. A study of the
  timing, intensity and evolution of the soft X-ray blue-wing shows that
  there is no simple relationship between hard and soft X-ray emissions;
  strong blue-wings sometimes result from relatively weak hard X-ray
  bursts; the burst responsible for the blue wing need not be the first
  or most intense burst associated with the flare; the blue-wing is found
  to follow very closely after the hard X-ray burst. We also discuss
  timing issues and why other researchers may have reached different
  conclusions on this matter.

Title: Magnetic Reconnection in the Solar Atmosphere
Authors: Bentley, R. D.; Mariska, J. T.
Bibcode: 1996ASPC..111.....B
Altcode: 1997ASPC..111.....B
  The following topics were dealt with: bright points, jets, emerging
  flux, coronal heating, flare observations, flare theory, larger
  structures and coronal ejections.

Title: YOHKOH observations of solar limb flares
Authors: Bentley, R. D.; Mariska, J. T.; Sakao, T.
Bibcode: 1996ASPC..109..107B
Altcode: 1996csss....9..107B
  No abstract at ADS

Title: Mass Motions in Flares
Authors: Bentley, R. D.
Bibcode: 1996mpsa.conf..177B
Altcode: 1996IAUCo.153..177B
  No abstract at ADS

Title: Hard and Soft X-ray Observations of Solar Limb Flares
Authors: Mariska, J. T.; Sakao, T.; Bentley, R. D.
Bibcode: 1996mpsa.conf..523M
Altcode: 1996IAUCo.153..523M
  No abstract at ADS

Title: Temperature Structure of Active Regions Deduced from the
    Helium-Like Sulphur Lines
Authors: Watanabe, Tetsuya; Haka, Hirohisa; Shimizu, Toshifumi; Hiei,
   Eijiro; Bentley, Robert D.; Lang, James; Phillips, Kenneth J. H.; David
   Pike, C.; Fludra, Andrzej; Bromage, Barbara J. I.; Mariska, John T.
Bibcode: 1995SoPh..157..169W
Altcode:
  Solar active-region temperatures have been determined from the full-Sun
  spectra of helium-like sulphur (SXV) observed by the Bragg Crystal
  Spectrometer on board theYohkoh satellite. The average temperature
  deduced from SXV is demonstrated to vary with the solar activity level:
  A temperature of 2.5 × 10<SUP>6</SUP> K is derived from the spectra
  taken during low solar activity, similar to the general corona, while
  4 × 10<SUP>6</SUP> K is obtained during a higher activity phase. For
  the latter, the high-temperature tail of the differential emission
  measure of active regions is found most likely due to the superposition
  of numerous flare-like events (micro/nano-flares).

Title: Hard and Soft X-Ray Observations of Solar Limb Flares
Authors: Mariska, J. T.; Sakao, T.; Bentley, R. D.
Bibcode: 1995SPD....26.1312M
Altcode: 1995BAAS...27..989M
  No abstract at ADS

Title: Hydra — A 3-dimensional electron and ion hot plasma
    instrument for the POLAR spacecraft of the GGS mission
Authors: Scudder, J.; Hunsacker, F.; Miller, G.; Lobell, J.;
   Zawistowski, T.; Ogilvie, K.; Keller, J.; Chornay, D.; Herrero, F.;
   Fitzenreiter, R.; Fairfield, D.; Needell, J.; Bodet, D.; Googins,
   J.; Kletzing, C.; Torbert, R.; Vandiver, J.; Bentley, R.; Fillius,
   W.; McIlwain, C.; Whipple, E.; Korth, A.
Bibcode: 1995SSRv...71..459S
Altcode:
  HYDRA is an experimental hot plasma investigation for the POLAR
  spacecraft of the GGS program. A consortium of institutions has
  designed a suite of particle analyzers that sample the velocity space
  of electron and ions between ≃2 keV/q 35 keV/q in three dimensions,
  with a routine time resolution of 0.5 s. Routine coverage of velocity
  space will be accomplished with an angular homogeneity assumption of
  ≃16°, appropriate for subsonic plasmas, but with special ≃1.5°
  resolution for electrons with energies between 100 eV and 10 keV along
  and opposed to the local magnetic field. This instrument produces 4.9
  kilobits s<SUP>-1</SUP> to the telemetry, consumes on average 14 W and
  requires 18.7 kg for deployment including its internal shielding. The
  scientific objectives for the polar magnetosphere fall into four broad
  categories: (1) those to define the ambient kinetic regimes of ions and
  electrons; (2) those to elucidate the magnetohydrodynamic responses
  in these regimes; (3) those to assess the particle populations with
  high time resolution; and (4) those to determine the global topology
  of the magnetic field. In thefirst group are issues of identifying the
  origins of particles at high magnetic latitudes, their energization,
  the altitude dependence of the forces, including parallel electric
  fields they have traversed. In thesecond group are the physics of the
  fluid flows, regimes of current, and plasma depletion zones during
  quiescent and disturbed magnetic conditions. In thethird group is the
  exploration of the processes that accompany the rapid time variations
  known to occur in the auroral zone, cusp and entry layers as they
  affect the flow of mass, momentum and energy in the auroral region. In
  thefourth class of objectives are studies in conjunction with the SWE
  measurements of the Strahl in the solar wind that exploit the small
  gyroradius of thermal electrons to detect those magnetic field lines
  that penetrate the auroral region that are directly ‘open’ to
  interplanetary space where, for example, the Polar Rain is observed.

Title: YOHKOH Bragg Crystal Spectrometer light curves for CA 29(3.1633
- 3.1933 A): 1 October 1993 - 30 September 1994
Authors: Mariska, John T.; Bentley, R. D.; Pike, C. D.
Bibcode: 1994YBCSCrept.....M
Altcode:
  This memorandum report summarizes the data produced during the third
  year of operation by the Bragg Crystal Spectrometer (BCS) on the Yohkoh
  spacecraft. Each page shows the total count rate in the Ca XIX channel
  of the BCS for a single day. This channel nominally observes the Sun in
  the wavelength range from 3.1633 to 3.1933 A. These plots are useful
  for identifying flare data for further analysis and for determining
  the data file name and tape name that contains the data.

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.
Bibcode: 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.
Bibcode: 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: 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.
Bibcode: 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.
Bibcode: 1994ASPC...64..402D
Altcode: 1994csss....8..402D
  No abstract at ADS

Title: Yohkoh Observations from the Onset of Several Flares
Authors: Bentley, R. D.; YOHKOH Team
Bibcode: 1994ddpn.conf..435B
Altcode:
  No abstract at ADS

Title: The Relationship Between the Soft X-Ray Blue Wing and the
    Hard X-Ray Burst
Authors: Bentley, R. D.
Bibcode: 1994xspy.conf...87B
Altcode:
  No abstract at ADS

Title: The Yohkoh mission: Instruments and recent results
Authors: Bentley, R. D.; YOHKOH Team
Bibcode: 1994LNP...432..311B
Altcode: 1994LNPM...11..311B
  The Yohkoh spacecraft was launched on 30 August, 1991 by the Japanese
  Institute of Space and Astronautical Science. The instruments, which
  include hard and soft X-ray imaging telescopes, a Bragg spectrometer and
  wide band full sun spectrometers, (which cover the energy range 2 kev to
  10 MeV), were described. Results obtained from these instruments were
  presented with special emphasis on data from the soft X-ray telescope
  which views the Sun in the 0.2 - 3 keV range with an angular resolution
  of 2.5 arc sec. Videos made from SXT datas were also presented at
  the meeting.

Title: Temperature Structure of Active Regions Deduced from the
    Helium-Like Sulphur Lines
Authors: Watanabe, T.; Hara, H.; Shimizu, T.; Hiei, E.; Mariska,
   J. T.; Bentley, R. D.; Fludra, A.; Lang, J.; Phillips, K. J. H.;
   Pike, C. D.; Bromage, B. J. I.
Bibcode: 1994xspy.conf...55W
Altcode:
  No abstract at ADS

Title: Flare Plasma Dynamics Observed with the YOHKOH Bragg Crystal
    Spectrometer. I. Properties of the CA XIX Resonance Line
Authors: Mariska, John T.; Doschek, G. A.; Bentley, R. D.
Bibcode: 1993ApJ...419..418M
Altcode:
  Using data from the Bragg crystal spectrometer on the Yohkoh spacecraft
  we have computed measures of the total intensity, centroid position,
  and line width for the resonance line of Ca xix during the rise phase
  and after maximum for 219 solar flares. The difference between the
  centroid positions early and late in each flare yields a measure
  of the line-of-sight velocity shift of the line centroid. We find
  a trend in the average value of the centroid shift with distance
  from Sun center suggesting radial mass motions with a characteristic
  velocity of 58 km s<SUP>-1</SUP>. There is a correlation between the
  rise-phase line widths and the centroid shift. We find no correlation
  between the centroid shift and the peak intensity, rise time, and
  total flare duration; and no correlation between the line width and
  the distance from Sun center, the peak intensity, rise time, and total
  flare duration. These results do not conclusively support or refute
  the simple electron-beam-driven model or the thermal model for the
  rise phase of a solar flare.

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.
Bibcode: 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.
Bibcode: 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.
Bibcode: 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: Flare Plasma Dynamics Observed with the Yohkoh Bragg Crystal
    Spectrometer
Authors: Mariska, J. T.; Doschek, G. A.; Bentley, R. D.
Bibcode: 1993BAAS...25Q1178M
Altcode:
  No abstract at ADS

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.
Bibcode: 1993BAAS...25.1189R
Altcode:
  No abstract at ADS

Title: The Yohkoh Software and Database System
Authors: Morrison, M. D.; Freeland, S. L.; Lemen, J. R.; Acton, L. W.;
   Bentley, R. D.
Bibcode: 1993BAAS...25R1188M
Altcode:
  No abstract at ADS

Title: YOHKOH Bragg Crystal Spectrometer light curves for CA XIX
(3.1631-3.1912A): 1 October 1991 - 30 September 1992
Authors: Mariska, John T.; Bentley, R. D.; Pike, C. D.
Bibcode: 1993YBCSCrept.....M
Altcode:
  This Memo Report summarizes the data produced during the first year
  of operation by the Bragg Crystal Spectrometer (BCS) on the Yohkoh
  spacecraft. Each page shows the total count rate in the Ca XIX channel
  of the BCS for a single day. This channel nominally observes the Sun in
  the wavelength range from 3.1631 to 3.1912 A. These plots are useful
  for identifying flare data for further analysis and for determining
  the data file name and tape name that contain the data.

Title: Dynamics of flaring loops. III - Interpretation of flare
    evolution in the emission measure-temperature diagram
Authors: Sylwester, B.; Sylwester, J.; Serio, S.; Reale, F.; Bentley,
   R. D.; Fludra, A.
Bibcode: 1993A&A...267..586S
Altcode:
  The aim of the paper is to illustrate the application of the
  density-temperature diagrams discussed by Jakimiec (1992) to
  interpretation of soft X-ray measurements, namely, calcium spectra
  recorded by the Solar Maximum Mission Bent Crystal Spectrometer. Using
  the emission measure and the temperature values derived for a set
  of hydrodynamic flare models discussed in previous papers, we have
  obtained and analyzed the (sq rt epsilon-T) counterparts of the (N-T)
  diagrams. Inspection of these diagrams reveals that they qualitatively
  resemble the (N-T) diagrams. The inclinations of the decay trajectories
  make the main difference. Next, we have performed a comparison of the
  modeled and observed flare evolutionary trajectories. This comparison
  allowed us to identify characteristic cases of evolution during the
  decay phase. We have discussed time variations of the heating rate
  for selected observed flares. The results of this paper illustrate
  how to use the diagnostic diagrams in the interpretation of flare soft
  X-ray measurements.

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.
Bibcode: 1993uxrs.conf..542F
Altcode: 1993uxsa.conf..542F
  No abstract at ADS

Title: Objectives of RESIK solar concave soft X-ray spectrometer
    for CORONAS-F mission.
Authors: Sylwester, Janusz; Bentley, R. D.
Bibcode: 1992ESASP.348..357S
Altcode: 1992cscl.work..357S
  Several institutes are involved in construction of the high sensitivity
  soft X-ray spectrometer RESIK, to be flown aboard the Russian CORONAS-F
  satellite in 1994/95. The scientific objectives of the instrument are
  discussed, arising as a compromise between the scientific interests and
  constrained by good quality large area crystals obtainable, detector
  dimensions and the geometry of Bragg concave crystal reflection. Four
  bands have been selected to perform measurements of the solar active
  region and flare spectra: 2.97 - 3.24 Å, 3.15 - 3.25 Å, 4.95 - 5.15
  Å, and 6.50 - 7.19 Å. Special "Dopplerometer" arrangement of the
  crystals will allow to assign "absolute" wavelength scale and determine
  the role of directed and turbulent flows in the source. Interpretation
  of the line and continuum intensities will permit to derive the
  differential emission measure for plasma temperatures T &gt; 3MK, and
  to determine the composition (relative to H) of the coronal plasma for
  many elements including these with different first ionization potential.

Title: Helium-Like Sulphur Emission Lines in Solar Active Regions
    and Their Sub-C Class Variability
Authors: Watanabe, Tetsuya; Hiei, Eijiro; Lang, James; Culhane,
   J. Leonard; Bentley, Robert D.; Doschek, George A.; Bromage, Barbara
   J. I.; Brown, Charles M.; Feldman, Uri; Fludra, Andrzej; Kato, Takako;
   Payne, Jeffrey
Bibcode: 1992PASJ...44L.141W
Altcode:
  Helium-like sulphur spectra (formation temperature, T_m ~ 18times
  10(6) K) from coronal active regions are being obtained by the Bragg
  Crystal Spectrometer onboard the Yohkoh mission. The average electron
  temperatures of the quiescent active regions deduced from the full-disk
  integrated sulphur spectra are 3.5--4 times 10(6) K. The temporal
  behavior of the emission lines in the sub-C level events shows that
  hot plasmas (T &gt; 10(7) K) can be produced in these weak events.

Title: Observations of Several Small Flares with the Bragg Crystal
    Spectrometer on YOHKOH
Authors: Culhane, J. Leonard; Fludra, Andrzej; Bentley, Robert D.;
   Doschek, George A.; Watanabe, Tetsuya; Hiei, Eijiro; Lang, James;
   Carter, Martin K.; Mariska, John T.; Phillips, Andrew T.; Phillips,
   Kenneth J. H.; Pike, C. David; Sterling, Alphonse C.
Bibcode: 1992PASJ...44L.101C
Altcode:
  We have analysed data from two flares of GOES class C7.1 and C8.5
  observed by the Yohkoh Bragg Crystal Spectrometer. The high sensitivity
  of the Yohkoh instrument allows us to observe the very early stages of
  flare development and to study small events with a high signal-to-noise
  ratio. Spectral fitting programs have been used to derive plasma
  temperatures, emission measures and velocities from spectra of S XV,
  Ca XIX and Fe XXV. Large plasma motions indicative of chromospheric
  evaporation have been found. A more detailed analysis of a flare which
  occurred on 1991 October 30 is presented.

Title: The Status of YOHKOH in Orbit: an Introduction to the Initial
    Scientific Results
Authors: Ogawara, Yoshiaki; Acton, Loren W.; Bentley, Robert D.;
   Bruner, Marilyn E.; Culhane, J. Leonard; Hiei, Eijiro; Hirayama,
   Tadashi; Hudson, Hugh S.; Kosugi, Takeo; Lemen, James R.; Strong, Keith
   T.; Tsuneta, Saku; Uchida, Yutaka; Watanabe, Tetsuya; Yoshimori, Masato
Bibcode: 1992PASJ...44L..41O
Altcode:
  In this introductory article accompanying the initial scientific
  papers from the Yohkoh mission, we briefly summarize the design
  and in-orbit function of the spacecraft and its four scientific
  instruments. Although these initial results include mainly studies
  based upon individual Yohkoh experiments at this early stage, there
  are also analyses of combined data sets provided by several on-board
  and ground-based instruments in progress. The results presented here,
  and anticipated future results, suggest that the Yohkoh observations
  with their comprehensive coverage of solar high-energy phenomena will
  come to represent a significant milestone in the progress of solar
  physics. This will be true not only regarding flares, but also for
  fainter coronal structures and even coronal holes.

Title: The YOHKOH mission for high-energy solar physics
Authors: Acton, L.; Tsuneta, S.; Ogawara, Y.; Bentley, R.; Bruner, M.;
   Canfield, R.; Culhane, L.; Doschek, G.; Hiei, E.; Hirayama, T. Hudson,
   H.; Kosugi, T.; Lang, J.; Lemen, J.; Nishimura, J.; Makishima, K.;
   Uchida, Y.; Watanabe, T.
Bibcode: 1992Sci...258..618A
Altcode: 1992Sci...258..591A
  Data on solar flare mechanisms and the sun's corona will be generated
  by Japan's Yohkoh satellite's X-ray imaging sensors and X-ray and
  gamma-ray spectrometers. It is noted that the X-ray corona above active
  regions expands, in some cases almost continually, in contradiction of
  the widely accepted model of magnetohydrostatic equilibrium in such
  regions. Flaring X-ray bright points have been discovered to often
  involve ejecta into an adjacent, much larger and fainter magnetic loop,
  which brightens along its length at speeds up to 1000 km/sec.

Title: YOHKOH Bragg Crystal Spectrometer Observations of the Dynamics
    and Temperature Behavior of a Soft X-Ray Flare
Authors: Doschek, George A.; Mariska, John T.; Watanabe, Tetsuya;
   Hiei, Eijiro; Lang, James; Culhane, J. Leonard; Bentley, Robert D.;
   Brown, Charles M.; Feldman, Uri; Phillips, Andrew T.; Phillips,
   Kenneth J. H.; Sterling, Alphonse C.
Bibcode: 1992PASJ...44L..95D
Altcode:
  We describe X-ray spectra of an M1.5 flare that occurred on 1991
  November 9, starting at about 0313 UT. This flare is unusual in that
  very intense blueshifted components are observed in the resonance
  lines of Fe XXV, Ca XIX, and S XV. During the onset of the flare,
  the resonance lines of Ca XIX and Fe XXV are primarily due to
  this blueshifted component, which from the Doppler effect indicates
  line-of-sight speeds and turbulent motions that in combination extend
  up to 800 km s(-1) .

Title: The Performance of the YOHKOH Bragg Crystal Spectrometer
Authors: Lang, James; Bentley, Robert D.; Brown, Charles M.; Culhane,
   J. Leonard; Doschek, George A.; Watanabe, Tetsuya; Hiei, Eijiro;
   Deslattes, Richard D.; Fludra, Andrzej; Guttridge, Philip R.; Magraw,
   John E.; Payne, Jeffrey; Pike, C. David; Trow, Matthew W.
Bibcode: 1992PASJ...44L..55L
Altcode:
  An overview of the Yohkoh Bragg Crystal Spectrometer is given,
  complemented by details of the laboratory testing prior to launch. The
  in-orbit performance of the instrument is described.

Title: The EUV mini-survey with the ROSAT wide field camera.
Authors: Pounds, K. A.; Abbey, A. F.; Barstow, M. A.; Bentley, R. D.;
   Bewick, A.; Breeveld, E. R.; Cole, R. E.; Courtier, G. M.; Deeley, M.;
   Denby, M.; Goodall, C. V.; Gourlay, J. A.; Guttridge, P. R.; Harris,
   A. W.; Huckle, H. E.; Kent, B. J.; Lieu, R.; McCalden, A. J.; Page,
   C. G.; Pankiewicz, G. S.; Ponman, T. J.; Pye, J. P.; Reading, D. H.;
   Richards, A. G.; Ricketts, M. J.; Rochester, G. K.; Sansom, A. E.;
   Sembay, S. E.; Sidher, S.; Sims, M. R.; Spragg, J. E.; Sumner, T. J.;
   Swinyard, B. M.; Vallance, R. J.; Watson, D. J.; Watson, M. G.; Wells,
   A. A.; Willingale, R.; Wright, J. S.
Bibcode: 1991MNRAS.253..364P
Altcode:
  Following a successful launch on 1990 June 1, the ROSAT spacecraft and
  its payload, consisting of an X-ray and an EUV telescope, underwent
  two months of in-orbit calibration and detailed performance checks. A
  preliminary observation of a small section of the sky, carried out
  over July 11-16 (the `mini-survey') showed all ROSAT systems to
  be functioning well and has allowed predictions to be made on the
  ultimate productivity of both ROSAT all-sky surveys. An analysis of
  the mini-survey data from the UK Wide Field Camera, has revealed 35
  EUV sources, including several white dwarf stars, a variety of active
  cool stars and several other objects. In all, 23 sources have probable
  optical counterparts. Consideration of the effective exposure and sky
  coverage in the mini- survey allows the prediction that the recently
  completed ROSAT all-sky survey will yield in excess of a thousand new
  EUV sources.

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.
Bibcode: 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: SOLAR-A Reformatted Data Files and Observing Log
Authors: Morrison, M. D.; Lemen, J. R.; Acton, L. W.; Bentley, R. D.;
   Kosugi, T.; Tsuneta, S.; Ogawara, Y.; Watanabe, T.
Bibcode: 1991SoPh..136..105M
Altcode:
  All of the SOLAR-A telemetry data will be reformatted before
  distribution to the analysis computers and the various users. This
  paper gives an overview of the files which will be created and the
  format and organization which the files will use. The organization
  has been chosen to be efficient in space, to ease access to the data,
  and to allow for the data to be transportable to different machines. An
  observing log file will be created automatically using the reformatted
  data files as the input. It will be possible to perform searches with
  the observing log to list cases where instruments are in certain modes
  and/or seeing certain signal levels.

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.
Bibcode: 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.
Bibcode: 1991LNP...387...22C
Altcode: 1991fpsa.conf...22C
  No abstract at ADS

Title: Early results from the ROSAT Wide Field Camera
Authors: Barstow, M. A.; Abbey, A. F.; Cole, R. E.; Denby, M.; Page,
   C. G.; Pankiewicz, G. S.; Pounds, K. A.; Pye, J. P.; Sansom, A. E.;
   Sims, M. R.; Spragg, J. E.; Watson, D. J.; Wells, A. A.; Willingale,
   R.; Courtier, G. M.; Gourlay, J. A.; Harris, A. W.; Kent, B. J.;
   Reading, D. H.; Richards, A. G.; Swinyard, B. M.; Wright, J. S.;
   Goodall, C. V.; Bentley, R. D.; Breeveld, E. R.; Guttridge, P. R.;
   Huckle, H. E.; McCalden, A. J.; Bewick, A.; Rochester, G. K.; Sumner,
   T. J.
Bibcode: 1991ASIC..336...99B
Altcode: 1991whdw.conf...99B
  No abstract at ADS

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.
Bibcode: 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: On the Dependence of Solar Flare X-Ray Spectral Line Intensity
    Ratios of Highly Ionized Sulfur, Calcium, and Iron on Electron
    Temperature, Differential Emission Measure, and Atomic Physics
Authors: Doschek, G. A.; Fludra, A.; Bentley, R. D.; Lang, J.;
   Phillips, K. J. H.; Watanabe, T.
Bibcode: 1990ApJ...358..665D
Altcode:
  This paper focuses on what can be learned about the emission measure
  distribution and certain atomic physics parameters from spectral lines
  of highly ionized ions of sulfur, calcium, and iron that appear in
  solar flare spectra. The particular lines chosen for analysis allow the
  electron temperature to be determined independently of the assumption
  of ionization equilibrium. An attempt is made to find emission measure
  models based on selected functional dependences of emission measure
  on temperature that reproduce the observed temperatures deduced from
  spectral line ratios as well as the relative intensities of resonance
  lines of different elements.

Title: Investigation of non-uniform heating during the decay phase
    of solar flares
Authors: Sylwester, B.; Sylwester, J.; Bentley, R. D.; Fludra, A.
Bibcode: 1990SoPh..126..177S
Altcode:
  We have analysed X-ray spectra of 13 solar flares as obtained
  by the Bent Crystal Spectrometer (BCS) on the Solar Maximum
  Mission. In particular, we have examined the observed ratio of
  T<SUB>Fe</SUB>/T<SUB>Ca</SUB> where T<SUB>Fe</SUB> and T<SUB>Ca</SUB>
  are the temperatures obtained from the FeXXV and CaXIX spectra,
  respectively. In order to simplify the investigation we have analysed
  only flares which reach quasi-steady-state during the decay. It
  turned out that the observed ratios cannot be explained by a model
  consisting of a single, uniformly heated loop, with a constant or
  variable cross-sectional area. We propose that this problem may be
  solved by introducing some distribution of the heating function across
  the flaring loop. This model has been tested by detailed calculations.

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.
Bibcode: 1990PDHO....7..266F
Altcode: 1990ESPM....6..266F; 1990dysu.conf..266F
  No abstract at ADS

Title: Study of Non-Uniform Heating in Solar Flares
Authors: Sylwester, B.; Sylwester, J.; Jakimiec, J.; Serio, S.; Reale,
   F.; Bentley, R. D.; Fludra, A.
Bibcode: 1990PDHO....7..255S
Altcode: 1990ESPM....6..255S; 1990dysu.conf..255S
  The authors have analyzed the ratios of the temperatures derived from Fe
  and Ca spectra (T<SUB>Fe</SUB>/T<SUB>Ca</SUB>) for the rising phase of
  11 solar flares. Corresponding hydrodynamic models have been calculated
  and the obtained results are compared with the observational data for
  selected flares.

Title: Position-sensitive proportional counter for the Bragg Crystal
    Spectrometer on Solar-A
Authors: Lapington, J. S.; Trow, M. W.; Bentley, R. D.; Cilhane, J. L.
Bibcode: 1989SPIE.1159..252L
Altcode:
  The gas proportional counter used for X-ray detection on the Solar-A
  Bragg Crystal Spectrometer Instrument is described. The sealed detector
  utilizes a multianode geometry together with a wedge and wedge (or
  backgammon) cathode pattern to provide one-dimensional imaging along
  the dispersion axis. The development program has now arrived at a
  design for the prototype detector. Results of the imaging performance,
  energy resolution, and count-rate capability are psesented.

Title: Turbulent and Directed Plasma Motions in Solar Flares
Authors: Fludra, A.; Lemen, J. R.; Jakimiec, J.; Bentley, R. D.;
   Sylwester, J.
Bibcode: 1989ApJ...344..991F
Altcode:
  An improved method for fitting asymmetric soft X-ray line profiles
  from solar flares is presented. A two-component model is used where one
  component represents the total emission from directed upflow plasma and
  the other the emission from the plasma at rest. Unlike previous methods,
  the width of the moving component is independent from that of the
  stationary component. Time variations of flare plasma characteristics
  (i.e., temperature, emission measure of moving and stationary plasma,
  upflow and turbulent velocities) are derived from the Ca XIX and Fe XXV
  spectra recorded by the Bent Crystal Spectrometer on the Solar Maximum
  Mission. The fitting technique provides a statistical estimation
  for the uncertainties in the fitting parameters. The relationship
  between the directed and turbulent motions has been studied, and
  a correlation of the random and directed motions has been found in
  some flares with intensive plasma upflows. Mean temperatures of the
  upflowing and stationary plasmas are compared for the first time from
  ratios of calcium to iron X-ray line intensities. Finally, evidence
  for turbulent motions and the possibility of plasma upflow late into
  the decay phase is presented and discussed.

Title: Comparison of the Microwave and Soft X-Ray Emission above
    a Sunspot
Authors: Siarkowski, M.; Sylwester, J.; Jakimiec, J.; Bentley, R. D.
Bibcode: 1989SoPh..119...65S
Altcode:
  The Westerbork Synthesis Radio Telescope (WSRT) 6 cm radio observations
  of the active region HL 16864 large spot (Strong, Alissandrakis,
  and Kundu, 1984) are compared with X-ray data obtained from the Flat
  Crystal Spectrometer (FCS) onboard the Solar Maximum Mission satellite
  on May 25, 1980. The X-ray data confirm the presence of a temperature
  depression above the spot umbra in agreement with suggestions obtained
  from radio data analysis. Significant differences in the spatial
  distribution of both kinds of emission observed in the corona above
  this spot are attributed mainly to the strong resonant character of the
  cyclotron radio radiation. Some differences are also caused by both
  the relatively low efficiency and the low spatial resolution of the
  FCS. Deconvolution of X-ray images allows to see the new structures
  and enhances the mutual correlation between X-ray and radio pictures.

Title: Flare energetics.
Authors: Wu, S. T.; de Jager, C.; Dennis, B. R.; Hudson, H. S.;
   Simnett, G. M.; Strong, K. T.; Bentley, R. D.; Bornmann, P. L.; Bruner,
   M. E.; Cargill, P. J.; Crannell, C. J.; Doyle, J. G.; Hyder, C. L.;
   Kopp, R. A.; Lemen, J. R.; Martin, S. F.; Pallavicini, R.; Peres,
   G.; Serio, S.; Sylwester, J.; Veck, N. J.
Bibcode: 1989epos.conf..377W
Altcode:
  The authors have sought to establish a comprehensive and self-consistent
  picture of the sources and transport of energy within a flare. To
  achieve this goal, they chose five flares in 1980 that were well
  observed with instruments on the Solar Maximum Mission, and with other
  space-borne and ground-based instruments. The events were chosen to
  represent various types of flares. Details of the observations available
  for them and the corresponding physical parameters derived from these
  data are presented. The flares were studied from two perspectives,
  the impulsive and gradual phases, and then the results were compared
  to obtain the overall picture of the energetics of these flares. The
  authors also discuss the role that modeling can play in estimating the
  total energy of a flare when the observationally determined parameters
  are used as the input to a numerical model. Finally, a critique of
  our current understanding of flare energetics and the methods used to
  determine various energetics terms is outlined, and possible future
  directions of research in this area are suggested.

Title: Preflare activity.
Authors: Priest, E. R.; Gaizauskas, V.; Hagyard, M. J.; Schmahl, E. J.;
   Webb, D. F.; Cargill, P.; Forbes, T. G.; Hood, A. W.; Steinolfson,
   R. S.; Chapman, G. A.; Deloach, A. C.; Gary, G. A.; Jones, H. P.;
   Karpen, J. T.; Martres, M. -J.; Porter, J. G.; Schmieder, B.; Smith,
   J. B., Jr.; Toomre, J.; Woodgate, B.; Waggett, P.; Bentley, R.;
   Hurford, G.; Schadee, A.; Schrijver, J.; Harrison, R.; Martens, P.
Bibcode: 1989epos.conf....1P
Altcode:
  Contents: 1. Introduction. 2. Magnetohydrodynamic
  instability. 3. Preflare magnetic and velocity fields. 4. Coronal
  manifestations of preflare activity.

Title: Largescale Magnetic Field Phenomena
Authors: Harrison, R. A.; Bentley, R. D.; Brosius, J.; Dwivedi,
   B. N.; Jardine, M.; Klimchuk, J. A.; Kundu, M. R.; Pearce, G.; Saba,
   J.; Sakurai, T.; Schmahl, E. J.; Schmelz, J.; Sime, D. G.; Steele,
   C. D. C.; Sun, M. T.; Tappin, S. J.; Waljeski, K.; Wang, A. H.; Wu,
   S. T.
Bibcode: 1989tnti.conf....1H
Altcode:
  No abstract at ADS

Title: Time variations of the calcium elemental abundance in flares
    from NOAA active regions 2562 and 2779.
Authors: Sylwester, J.; Zolcinski-Couet, M. -C.; Bentley, R. D.;
   Lemen, J. R.
Bibcode: 1988JPhys..49..189S
Altcode: 1988IAUCo.102..189S
  Analysis of flare spectra obtained with the Bent Crystal Spectrometer
  aboard the Solar Maximum Mission (SMM) satellite enables the
  determination of the fluxes in the resonance (w) line of Ca XIX and
  the near-by continuum. The line-to-continuum intensity ratio is a
  sensitive measure of the calcium elemental abundance (A<SUB>Ca</SUB>)
  relative to hydrogen in the emitting plasma. The authors analyse
  the variations of A<SUB>Ca</SUB> for flares which occurred in two
  active regions well observed by SMM. They conclude that it is not
  possible to correlate the abundance variations with the time of the
  flare occurrence as suggested in an earlier paper for flares produced
  from a single active region. Further, the authors find no convincing
  correlation of abundance variation with any other flare characteristics.

Title: Intercomparison of flare observations with two SMM
spectrometers: BCS and HXIS
Authors: Jakimiec, J.; Prés, P.; Fludra, A.; Bentley, R. D.; Lemen,
   J. R.; Mewe, R.; Schrijver, J.; Sylwester, J.
Bibcode: 1988AdSpR...8k.231J
Altcode: 1988AdSpR...8..231J
  The temperature diagnostics of hot flare plasma, obtained from two
  Solar Maximum Mission instruments (HXIS and BCS), is compared. A good
  general agreement between the HXIS and BCS-Fe temperature scales has
  been found. However, for the growth phase of some flares a systematic
  difference, T<SUB>HXIS</SUB>&gt;T<SUB>Fe</SUB>, has been found,
  which is not likely to be due to the typical non-thermal electron
  beams. Possible explanation of this effect is briefly discussed.

Title: Investigations of Turbulent and Direct Motions in Solar Flares
Authors: Bentley, R. D.; Fludra, A.; Lemen, J. R.; Jakimiec, J.;
   Sylwester, J.
Bibcode: 1987BAAS...19R.750B
Altcode:
  No abstract at ADS

Title: Variation in Calcium Abundance during Flares
Authors: Sylwester, J.; Lemen, J. R.; Mewe, R.; Bentley, R. D.;
   Sylwester, B.
Bibcode: 1987sman.work..123S
Altcode:
  The authors discuss the variation of the line-to-continuum ratio
  throughout the entire flare including the temperature rise phase.

Title: High-Temperature Plasma Diagnostics of Solar Flares and
    Comparison with Model Calculations
Authors: Jakimiec, J.; Sylwester, B.; Sylwester, J.; Lemen, J. R.;
   Mewe, R.; Bentley, R. D.; Peres, G.; Serio, S.; Schrijver, J.
Bibcode: 1987sman.work...91J
Altcode:
  The present state of flare diagnostics from X-ray spectra is briefly
  outlined. The authors discuss how improved diagnostic results can be
  used in flare heating process investigations.

Title: Flare energetics
Authors: Wu, S. T.; De Jager, C.; Dennis, B. R.; Hudson, H. S.;
   Simnett, G. M.; Strong, K. T.; Bentley, R. D.; Bornmann, P. L.;
   Bruner, M. E.; Cargill, P. J.
Bibcode: 1986epos.conf..5.1W
Altcode: 1986epos.confE...1W
  In this investigation of flare energetics, researchers sought
  to establish a comprehensive and self-consistent picture of the
  sources and transport of energy within a flare. To achieve this
  goal, they chose five flares in 1980 that were well observed with
  instruments on the Solar Maximum Mission, and with other space-borne
  and ground-based instruments. The events were chosen to represent
  various types of flares. Details of the observations available for
  them and the corresponding physical parameters derived from these
  data are presented. The flares were studied from two perspectives,
  the impulsive and gradual phases, and then the results were compared
  to obtain the overall picture of the energics of these flares. The
  role that modeling can play in estimating the total energy of a flare
  when the observationally determined parameters are used as the input
  to a numerical model is discussed. Finally, a critique of the current
  understanding of flare energetics and the methods used to determine
  various energetics terms is outlined, and possible future directions
  of research in this area are suggested.

Title: Characterization of the Total Flare Energy
Authors: Wu, S. T.; de Jager, C.; Dennis, B. R.; Hudson, H. S.;
   Simnett, G. M.; Strong, K. T.; Bentley, R. D.; Bornmann, P. L.; Bruner,
   M. E.; Cargill, P. J.; Crannell, C. J.; Doyle, J. G.; Hyder, C. L.;
   Kopp, R. A.; Lemen, J. R.; Martin, S. F.; Pallavicini, R.; Peres,
   G.; Serio, S.; Sylwester, J.; Veek, N. J.
Bibcode: 1986epos.conf.5.41W
Altcode: 1986epos.confE..41W
  No abstract at ADS

Title: Energetics of the Impulsive Phase
Authors: Wu, S. T.; de Jager, C.; Dennis, B. R.; Hudson, H. S.;
   Simnett, G. M.; Strong, K. T.; Bentley, R. D.; Bornmann, P. L.; Bruner,
   M. E.; Cargill, P. J.; Crannell, C. J.; Doyle, J. G.; Hyder, C. L.;
   Kopp, R. A.; Lemen, J. R.; Martin, S. F.; Pallavicini, R.; Peres,
   G.; Serio, S.; Sylwester, J.; Veek, N. J.
Bibcode: 1986epos.conf..5.5W
Altcode: 1986epos.confE...5W
  No abstract at ADS

Title: Coronal manifestations of preflare activity
Authors: Schmahl, E. J.; Webb, D. F.; Woodgate, B.; Waggett, P.;
   Bentley, R.; Hurford, G.; Schadee, A.; Schrijver, J.; Harrison, R.;
   Martens, P.
Bibcode: 1986epos.conf.1.48S
Altcode: 1986epos.confA..48S
  A variety of coronal manifestations of precursors or preheating for
  flares are discussed. Researchers found that almost everyone with a
  telescope sees something before flares. Whether an all-encompassing
  scenario will ever be developed is not at all clear at present. The
  clearest example of preflare activity appears to be activated filaments
  and their manifestations, which presumably are signatures of a changing
  magnetic field. But researchers have seen two similar eruptions, one
  without any evidence of emerging flux (Kundu et al., 1985) and the
  other with colliding poles (Simon et al., 1984). While the reconnection
  of flux is generally agreed to be required to energize a flare, the
  emergence of flux from below (at least on short timescales and in
  compact regions) does not appear to be a necessary condition. In some
  cases the cancelling of magnetic flux (Martin, 1984) by horizontal
  motions instead may provide the trigger (Priest, 1985) Researchers
  found similarities and some differences between these and previous
  observations. The similarities, besides the frequent involvement of
  filaments, include compact, multiple precursors which can occur both at
  and near (not at) the flare site, and the association between coronal
  sources and activity lower in the atmosphere (i.e., transition zone
  and chromosphere).

Title: Energetics of the Gradual Phase
Authors: Wu, S. T.; de Jager, C.; Dennis, B. R.; Hudson, H. S.;
   Simnett, G. M.; Strong, K. T.; Bentley, R. D.; Bornmann, P. L.; Bruner,
   M. E.; Cargill, P. J.; Crannell, C. J.; Doyle, J. G.; Hyder, C. L.;
   Kopp, R. A.; Lemen, J. R.; Martin, S. F.; Pallavicini, R.; Peres,
   G.; Serio, S.; Sylwester, J.; Veek, N. J.
Bibcode: 1986epos.conf.5.20W
Altcode: 1986epos.confE..20W
  No abstract at ADS

Title: Review of Impulsive Phase Phenomena
Authors: Wu, S. T.; de Jager, C.; Dennis, B. R.; Hudson, H. S.;
   Simnett, G. M.; Strong, K. T.; Bentley, R. D.; Bornmann, P. L.; Bruner,
   M. E.; Cargill, P. J.; Crannell, C. J.; Doyle, J. G.; Hyder, C. L.;
   Kopp, R. A.; Lemen, J. R.; Martin, S. F.; Pallavicini, R.; Peres,
   G.; Serio, S.; Sylwester, J.; Veek, N. J.
Bibcode: 1986epos.conf.5.60W
Altcode: 1986epos.confE..60W
  No abstract at ADS

Title: Flares Chosen for Energetics Study
Authors: Wu, S. T.; de Jager, C.; Dennis, B. R.; Hudson, H. S.;
   Simnett, G. M.; Strong, K. T.; Bentley, R. D.; Bornmann, P. L.; Bruner,
   M. E.; Cargill, P. J.; Crannell, C. J.; Doyle, J. G.; Hyder, C. L.;
   Kopp, R. A.; Lemen, J. R.; Martin, S. F.; Pallavicini, R.; Peres,
   G.; Serio, S.; Sylwester, J.; Veek, N. J.
Bibcode: 1986epos.conf.5.47W
Altcode: 1986epos.confE..47W
  No abstract at ADS

Title: Relationships among the Phases
Authors: Wu, S. T.; de Jager, C.; Dennis, B. R.; Hudson, H. S.;
   Simnett, G. M.; Strong, K. T.; Bentley, R. D.; Bornmann, P. L.; Bruner,
   M. E.; Cargill, P. J.; Crannell, C. J.; Doyle, J. G.; Hyder, C. L.;
   Kopp, R. A.; Lemen, J. R.; Martin, S. F.; Pallavicini, R.; Peres,
   G.; Serio, S.; Sylwester, J.; Veek, N. J.
Bibcode: 1986epos.conf.5.39W
Altcode: 1986epos.confE..39W
  No abstract at ADS

Title: Broadening of soft X-ray lines during the impulsive phase of
    solar flares - Random or directed mass motions?
Authors: Doyle, J. G.; Bentley, R. D.
Bibcode: 1986A&A...155..278D
Altcode:
  The authors present spectroscopic data for three flares obtained with
  the Bent Crystal Spectrometer flown in the Solar Maximum Mission in
  1980. This data is concerned with the structure of the Ca XIX resonance
  line at 3.176 Å during the impulsive phase of flares. On the basis of
  high time resolution (6s.) data, the authors suggest that the previous
  published results concerned with the excess broadening of the resonance
  line being due to bulk random mass motions may give an over-simplified
  picture. Instead the authors suggest that during this stage of the
  flare, the resonance line consists of many discrete features, which
  are interpreted as mass flows.

Title: Preflare activity.
Authors: Priest, E. R.; Gaizauskas, V.; Hagyard, M. J.; Schmahl, E. J.;
   Webb, D. F.; Cargill, P.; Forbes, T. G.; Hood, A. W.; Steinolfson,
   R. S.; Chapman, G. A.; Deloach, A. C.; Gary, G. A.; Jones, H. P.;
   Karpen, J. T.; Martres, M. -J.; Porter, J. G.; Schmieder, B.; Smith,
   J. B., Jr.; Toomre, J.; Woodgate, B.; Waggett, P.; Bentley, R.;
   Hurford, G.; Schadee, A.; Schrijver, J.; Harrison, R.; Martens, P.
Bibcode: 1986NASCP2439....1P
Altcode:
  Contents: 1. Introduction: the preflare state - a review of previous
  results. 2. Magnetohydrodynamic instability: magnetic reconnection,
  nonlinear tearing, nonlinear reconnection experiments, emerging flux and
  moving satellite sunspots, main phase reconnection in two-ribbon flares,
  magnetic instability responsible for filament eruption in two-ribbon
  flares. 3. Preflare magnetic and velocity fields: general morphology of
  the preflare magnetic field, magnetic field shear, electric currents in
  the preflare active region, characterization of the preflare velocity
  field, emerging flux. 4. Coronal manifestations of preflare activity:
  defining the preflare regime, specific illustrative events, comparison
  of preflare X-rays and ultraviolet, preflare microwave intensity and
  polarization changes, non-thermal precursors, precursors of coronal
  mass ejections, short-lived and long-lived HXIS sources as possible
  precursors.

Title: Observational evidences for coronal temperature depression
    above sunspot umbra
Authors: Siarkowski, M.; Bentley, R. D.; Jakimiec, J.; Sylwester, J.
Bibcode: 1986CoSka..15..677S
Altcode:
  Three large spots observed by the X-ray Polychromator on the Solar
  Maximum Mission satellite are analysed. The X-ray spectroheliograms were
  used to derive the two-dimensonal electron temperature distribution. For
  one of these spots, observed simultaneously by the Westerbork Synthesis
  Radiotelescope at 6 cm, the temperature minimum corresponds to the
  centre of a microwave ring structure. This confirms the existence of
  a temperature depression above the spot umbra.

Title: Differential emission measure distributions of Capella and
    σ<SUP>2</SUP> CrB
Authors: Mewe, R.; Schrijver, C. J.; Lemen, J. R.; Bentley, R. D.
Bibcode: 1986AdSpR...6h.133M
Altcode: 1986AdSpR...6..133M
  The active late-type stars Capella (α Aur G6III+F9III) and
  σ<SUP>2</SUP> CrB (F6V+GV) (X-ray candidate emitters underlined)
  were observed with the EXOSAT Transmission Grating Spectrometer
  (TGS) in the region 10-200 Å. We have made an analysis of the
  differential emission measure (DEM) distribution. The derived DEM
  peaks between 3 and 7 MK and above 10 MK. The results disagree with
  models for static loops as developed by Rosner, Tucker and Vaiana [1,
  hereafter referred to as RTV]: the contrast in emission between the
  maximal and lower temperatures in the loop is larger than predicted by
  the RTV model. Other models which predict DEM distributions falling
  off more steeply towards lower temperatures are briefly discussed:
  e.g. quasi-static loops with varying cross-sectional area or dynamic
  loops with strong downward flows.

Title: Physical conditions in a large flare loop on Nov. 1980 derived
    from SMM observations
Authors: Sylwester, B.; Sylwester, J.; Jakimiec, J.; Fludra, A.;
   Bentley, R. D.; Schrijver, J.
Bibcode: 1986CoSka..15..145S
Altcode:
  The authors present the study of a large X-ray loop related to the
  H-alpha 2N flare close to the center of the solar disc. Data from Solar
  Maximum Mission have been used in the analysis. The authors have derived
  the temperatures, densities and the geometrical parameters (length,
  diameter) for a hot core and for a cooler envelope of the flaring loop.

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.
Bibcode: 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: Orbital debris environment resulting from future activities
    in space
Authors: Simnett, G. M.; Phillips, K. J. H.; Bentley, R. D.
Bibcode: 1986AdSpR...6f.109S
Altcode: 1986AdSpR...6..109S
  A long-term evolution of space debris environment has been simulated by
  a numerical model. Based on previously published results in many 50-year
  runs of the ``dynamic model'', an ``average model'' is derived to reduce
  the computation time in order to effectively simulate a very-long-term
  evolution of space debris environment. The evolution of space debris
  environment is examined with two different future space activities
  in LEO: (1) Increase the yearly traffic input of new satellites by
  2%, 5%, 10%, 20%, and 50%; and (2) place ten large space structures
  of 100 meters in diameter in the year 1995 at either 500 km or 1000
  km altitude. The results indicate that in a 170-year span from 1983,
  every space activity listed above results in a rapid runaway of debris
  fluxes from objects of 4 mm or larger.

Title: Flare energetics.
Authors: Wu, S. T.; de Jager, C.; Dennis, B. R.; Hudson, H. S.;
   Simnett, G. M.; Strong, K. T.; Bentley, R. D.; Bornmann, P. L.; Bruner,
   M. E.; Cargill, P. J.; Crannell, C. J.; Doyle, J. G.; Hyder, C. L.;
   Kopp, R. A.; Lemen, J. R.; Martin, S. F.; Pallavicini, R.; Peres,
   G.; Serio, S.; Sylwester, J.; Veck, N. J.
Bibcode: 1986NASCP2439....5W
Altcode:
  In this investigation of flare energetics, the authors establish a
  comprehensive and self-consistent picture of the sources and transport
  of energy within a flare. They chose five flares in 1980 that were
  well observed with instruments on the SMM, and with other space-borne
  and ground-based instruments. Details of the observations available
  for them and the corresponding physical parameters derived from these
  data are presented. The flares were studied from two perspectives,
  the impulsive and gradual phases, and then the results were compared
  to obtain the overall picture of the energetics of these flares. The
  authors also discuss the role that modeling can play in estimating the
  total energy of a flare when the observationally determined parameters
  are used as the input to a numerical model.

Title: Determination of the calcium elemental abundance for 43 flares
    from SMM-XRP solar X-ray spectra
Authors: Lemen, J. R.; Sylwester, J.; Bentley, R. D.
Bibcode: 1986AdSpR...6f.245L
Altcode: 1986AdSpR...6..245L
  The helium and lithium-like X-ray transitions of Ca XVIII-XIX have been
  used to make an absolute measurement of the coronal calcium elemental
  abundance relative to hydrogen (A<SUB>Ca</SUB>) in solar flares. Cooling
  phase spectra of 43 flares obtained in channel 1 of the Bent Crystal
  Spectrometer (BCS) on the Solar Maximum Mission have been analyzed. The
  abundance is determined from the intensity ratio of the Ca XIX resonance
  line (<SUP>1</SUP>S<SUB>0</SUB> - <SUP>1</SUP>P<SUB>1</SUB>) and
  nearby continuum. A large variation is observed in the values of the
  derived abundances, ranging up to a factor of 2.5 between the extreme
  cases. This confirms the earlier results of Sylwester, Lemen, and Mewe
  [1], who investigated a smaller sample of flares. In addition to the
  variability of A<SUB>Ca</SUB> observed between different flares, it
  was suggested [1] that A<SUB>Ca</SUB> varies during the heating phase
  of some flares. We neglect this phenomenon in the present work, and
  concentrate on the cooling phase during which A<SUB>Ca</SUB> appears
  to remain constant for any individual flare. Attempts to correlate
  the A<SUB>Ca</SUB> measurements with other observable features are
  discussed.

Title: Soft X-ray emission from solar flares and active regions
Authors: Bentley, Robert Duncan
Bibcode: 1986PhDT.......170B
Altcode:
  No abstract at ADS

Title: The X-Ray Signature of Solar Coronal Mass Ejections
Authors: Harrison, R. A.; Waggett, P. W.; Bentley, R. D.; Phillips,
   K. J. H.; Bruner, M.; Dryer, M.; Simnett, G. M.
Bibcode: 1985SoPh...97..387H
Altcode:
  The coronal response to six solar X-ray flares has been investigated. At
  a time coincident with the projected onset of the white-light coronal
  mass ejection associated with each flare, there is a small, discrete
  soft X-ray enhancement. These enhancements (precursors) precede by
  typically ∼20 m the impulsive phase of the solar flare which is
  dominant by the time the coronal mass ejection has reached an altitude
  above 0.5 R<SUB>⊙</SUB>. We identify motions of hot X-ray emitting
  plasma, during the precursors, which may well be a signature of the
  mass ejection onsets. Further investigations have also revealed a
  second class of X-ray coronal transient, during the main phase of the
  flare. These appear to be associated with magnetic reconnection above
  post-flare loop systems.

Title: The X-ray signature of solar coronal mass ejections.
Authors: Harrison, R. A.; Waggett, P. W.; Bentley, R. D.; Phillips,
   K. J. H.; Bruner, M.; Dryer, M.; Simnett, G. M.
Bibcode: 1985RALR...84.....H
Altcode:
  The coronal response to six solar X-ray flares has been investigated. At
  a time coincident with the projected onset of the white-light coronal
  mass ejection with each flare, there is a small, discrete soft X-ray
  enhancement. These enhancements (precursors) precede by typically
  ≡20 m the impulsive phase of the solar flare which is dominant by
  the time the coronal mass ejection has reached an altitude above 0.5
  R_sun;. The authors identify motions of hot X-ray emitting plasma,
  during the precursors, which may well be a signature of the mass
  ejection onsets. Further investigations have also revealed a second
  class of X-ray coronal transients, during the main phase of the
  flare. These appear to be associated with magnetic reconnection above
  post-flare loop systems.

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.
Bibcode: 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: Recent Solar Observations from the X-Ray Polychromator on
    the Repaired SMM Satellite
Authors: Saba, J. L. R.; Slater, G. L.; Levay, M. X.; Smith, K. L.;
   Strong, K. T.; Bentley, R. D.; Lemen, J. R.; Caffey, R. R.; Freeland,
   S. L., Jr.; Mathur, D. P.; Phillips, K. J. H.; Waters, T. A.
Bibcode: 1984BAAS...16..726S
Altcode:
  No abstract at ADS

Title: Relationships of a growing magnetic flux region to flares
Authors: Martin, S. F.; Bentley, R. D.; Schadee, A.; Antalova, A.;
   Kucera, A.; Dezső, L.; Gesztelyi, L.; Harvey, K. L.; Jones, H.;
   Livi, S. H. B.; Wang, J.
Bibcode: 1984AdSpR...4g..61M
Altcode: 1984AdSpR...4...61M
  Some sites for solar flares are known to develop where new magnetic
  flux emerges and becomes abutted against opposite polarity pre-existing
  magnetic flux (review by Galzauskas/1/). We have identified and analyzed
  the evolution of such flare sites at the boundaries of a major new and
  growing magnetic flux region within a complex of active regions, Hale
  No. 16918. This analysis was done as a part of a continuing study of the
  circumstances associated with flares in Hale Region 16918, which was
  designated as an FBS target during the interval 18 - 23 June 1980. We
  studied the initiation and development of both major and minor flares in
  Hα images in relation to the identified potential flare sites at the
  boundaries of the growing flux region and to the general development
  of the new flux. This study lead to our recognition of a spectrum of
  possible relationships of growing flux regions to flares as follows:
  (1) intimate interaction with adjacent old flux - flare sites centered
  at new/old flux boundary, (2) forced or ``intimidated'' interaction
  in which new flux pushes old field having lower flux density towards a
  neighboring old polarity inversion line where a flare then takes place,
  (3) ``influential'' interaction - magnetic lines of force over an old
  polarity inversion line, typically containing a filament, reconnect to
  the new emerging flux; a flare occurs with erupting filament when the
  magnetic field overlying the filament becomes too weak to prevent its
  eruption, (4) inconsequential interaction - new flux region is too small
  or has wrong orientation for creating flare conditions, (5) incidental -
  flare occurs without any significant relationship to new flux regions.

Title: Differential emission measure analysis of hot-flare plasma
    from solar-maximum mission X-ray data
Authors: Jakimiec, J.; Sylwester, J.; Lemen, J. R.; Mewe, R.; Bentley,
   R. D.; Fludra, A.; Schrijver, J.; Sylwester, B.
Bibcode: 1984AdSpR...4g.203J
Altcode: 1984AdSpR...4..203J
  We have investigated differential emission measure (DEM) distribution
  of hot flare plasma (T&gt;10 MK) using SMM X-ray data from Bent Crystal
  Spectrometer (BCS) and Hard X-ray Imaging Spectrometer (HXIS). We have
  found that the analysis provide a very sensitive test of consistency
  of observational data coming from different instruments or different
  channels of the same instrument. This has allowed to eliminate some
  systematic differences contained in the analysed data. <P />Typical
  examples of the DEM distribution are discussed. It is stressed that
  these improvements in the multitemperature flare diagnostics are very
  important for the discussion of flare energetics.

Title: SMM flat crystal spectrometer data analysis of 7 April
    1980 flare.
Authors: Sylwester, B.; Sylwester, J.; Jakimiec, J.; Mewe, R.; Bentley,
   R. D.
Bibcode: 1983PDHO....5...85S
Altcode: 1984PDHO....5...85S
  The authors have analysed soft X-ray images of the 1B/M4 flare of 7
  April 1980 recorded by Flat Crystal Spectrometer aboard Solar Maximum
  Mission satellite. The X-ray flare consisted of two patches about 1
  arcmin apart. A comparison with magnetograms and white light images
  indicates that the two soft X-ray patches originate from two different
  loops or systems of loops. For two selected resolution elements of
  the X-ray pictures a detailed differential emission measure analysis
  has been carried out and time evolution of the mean electron density
  and thermal energy content has been investigated.

Title: Active region magnetic fields inferred from simultaneous VLA
    microwave maps, X-ray spectroheliograms, and magnetograms
Authors: Schmahl, E. J.; Kundu, M. R.; Strong, K. T.; Bentley, R. D.;
   Smith, J. B., Jr.; Krall, K. R.
Bibcode: 1982SoPh...80..233S
Altcode:
  A series of VLA maps at 6 cm wavelength have been generated from
  observations of a solar active region (NOAA 2363) on 29 and 30 March,
  1980. During the same period, X-ray spectroheliograms were acquired
  for this region in the lines of O VIII, Ne IX, Mg XI, Si XIII, S
  XV, and Fe XXV, with X-rayn Polychromator (XRP) aboard the Solar
  Maximum Mission (SMM). Intervals of relative quiescence (i.e.,
  when X-ray flares and centimeter wave bursts were not evident)
  were selected for microwave mapping. The resulting VLA maps have
  spatial resolution of 4″ × 4″, and generally show two or more
  sources whose slowly evolving substructures have spatial scales
  of 10″-30″. These maps were co-registered with Hα photographs
  (courtesy of AF/AWS SOON, Holloman and Ramey AFB) to an accuracy of ±
  8″. Similarly, the X-ray spectroheliograms have been co-registered
  with white light photographs to about the same accuracy. Magnetograms
  from KPNO and MSFC have also been co-aligned, and the magnetic X-ray,
  and microwave features compared. In general we have found that (a)
  the peaks of X-ray and 6 cm emission do not coincide, although (b) the
  sources in the two wavelength domains tend to overlap. These facts in
  themselves are evidence for the existence of opacity mechanisms other
  than thermal bremsstrahlung. In order to quantify this assertion, we
  have computed differential emission measures to derive densities and
  temperatures. Using these and calculated force-free magnetic fields from
  Kitt Peak magnetograms, we present an assessment of the mechanism of
  gyroresonance absorption at low harmonics of the electron gyrofrequency
  as the source of opacity responsible for the microwave features. We
  conclude that large-scale currents must be present in the active region
  loops to account for the bright 6 cm sources far from sunspots.

Title: Transient Ionization Conditions in Solar Flares. Analysis of
    High-Resolution X-Ray Spectra.
Authors: Schrijver, J.; Mewe, R.; Sylwester, J.; Strong, K. T.;
   Bentley, R. D.
Bibcode: 1982uxsa.collQ...4S
Altcode: 1982IAUCo..73Q...4S
  No abstract at ADS

Title: Relationship between a soft X-ray long duration event and an
    intense metric noise storm
Authors: Lantos, P.; Kerdraon, A.; Rapley, G. G.; Bentley, R. D.
Bibcode: 1981A&A...101...33L
Altcode:
  An example of a soft X-ray long duration event associated with the
  onset of a metric noise storm is reported. The event was observed by
  the Nancay Radioheliograph, operating at a frequency of 169 MHz, and
  the soft X-ray Polychromator experiment on board the Solar Maximum
  Mission on March 30, 1980 in the solar active region 2363. The soft
  X-ray event was found to exhibit all the features of a classical long
  duration event, including an extensive system of loops forming over the
  site of a disappearing H-alpha filament, H-alpha ribbons at the loop
  footprints, a centrimetric rise and fall burst and a coronal white light
  loop transient. The radio event detected simultaneously also displayed
  typical noise storm characteristics, however was particularly intense,
  extended over an unusually wide frequency range, and was located in
  the northern leg of the loop transient. The possible association of
  the southern leg of the loop transient with the long duration event
  leads to the suggestion that it is the loop itself which provides the
  physical link between the two events.

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.
Bibcode: 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.
Bibcode: 1981ApJ...244L.147G
Altcode:
  No abstract at ADS

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.
Bibcode: 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: Active Region Magnetic Fields
Authors: Smith, J. B., Jr.; Strong, K. T.; Schmahl, E. J.; Kundu,
   M. R.; Krall, K. R.; Bentley, R. D.
Bibcode: 1981BAAS...13..881S
Altcode:
  No abstract at ADS

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.
Bibcode: 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: 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.
Bibcode: 1981hea..conf..267G
Altcode:
  No abstract at ADS

Title: Characteristics of Soft X-ray Long Duration Events Observed
    by the SMM X-ray Polychromator
Authors: Bentley, R. D.; Rapley, C. G.
Bibcode: 1980BAAS...12..904B
Altcode:
  No abstract at ADS

Title: A study of a soft X-ray slow event associated with the
    commencement of a Type I noise storm
Authors: Rapley, C. G.; Bentley, R. D.; Lantos, P.; Kerdraon, A.
Bibcode: 1980BAAS...12..912R
Altcode:
  No abstract at ADS

Title: Morphology of Active Region and Flares
Authors: Bentley, R. D.
Bibcode: 1980BAAS...12..533B
Altcode:
  No abstract at ADS

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.
Bibcode: 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: The Mars penetrator telemetry and control system
Authors: Bentley, R. D.; Campbell, A. B.
Bibcode: 1975isa..conf..324B
Altcode:
  A new method for exploring the planet Mars has been proposed that will
  use ground-penetrating vehicles to carry scientific instruments below
  the Martian surface. The subsurface performance of various sequences of
  complicated experiments poses challenges in the design of the telemetry
  and control links. This article describes the overall mission, the
  penetrator, the constraints imposed by the mission and the penetrator,
  and a design for the telemetry/control system. This design uses a
  microprogrammed microprocessor; the sequences of commands are stored
  in a Read-Only-Memory (ROM), and a particular sequence is initiated by
  transmitting from the earth the address in the ROM that contains the
  first of the commands for the specific sequence to be performed. Data
  from the experiments are stored in a memory for later transmission
  to an orbiter that serves as a relay station for the command and data
  links with earth.

