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Abstract: This paper is the sixth article of a series which aims at describing the current developments of the SIMBAD database.
The main features of this semester are the new X Window interface, and the development of access to abstracts.
A new, more intuitive, user interface to SIMBAD, taking benefit of the X Window environment is now available for distribution to all potential SIMBAD users working in a Unix environment. It operates on X-terminals or Workstations running OSF/Motif.
X-SIMBAD is available as a client package, that you can install on your own workstation or computer system, and which will manage the connection and interactivity with the SIMBAD server in Strasbourg. The functionalities provided to the SIMBAD users (such as query modes, sampling procedure, on-line help, etc.) are presented as buttons, menu-buttons, or pull-down menus, in a simple and self-explanatory way.
The interface has been designed in coordination with similar projects (databases and information systems) in Europe and in the U.S. in order to bring up the best solutions for the users from the whole astronomical community.
It is important to note that this interface constitutes an additional layer on top of the existing software (the SIMBAD application, running since July '90 under Unix, working with line-by-line commands) which will be maintained and will remain accessible to those who wish to keep their familiar environment, or simply don't have access to X-terminals.
The user will be asked to install a piece of software on his/her own workstation or computer system, in order to run the X Window interface locally, as a client program. The main reason for using a client program is to optimize the response time by transmitting only database queries through the network, and leaving the screen painting to the local computer.
The new interface (xsimbad version 1.0) gives access to all the data and almost all the functionalities of the SIMBAD astronomical database. However the procedure for creating new formats is not part of the X Window interface (new formats can still be created using the command line syntax, and used under the new interface). New functionalities will also be gradually added, some of them specific to this interface: namely, those which need graphical capabilities (sky plots, and visualization of spectra or images).
The SIMBAD users will be kept informed of the evolution of this project, which should help a wider users' community to access the SIMBAD data, and bring to the current users a number of sophisticated new tools for browsing, retrieving, or visualizing the data.
In this early stage of development, all your remarks, comments, suggestions are welcome (send mail to email@example.com)!
The X-SIMBAD application can be fetched from the anonymous ftp space on the CDS archive server: ftp cdsarc.u-strasbg.fr (directory pub/simbad).
You will have to choose the application corresponding to your machine:
One of the key features of the SIMBAD astronomical database is the unique coverage of bibliographical references to objects. The bibliographic index contains references to stars from 1950 onwards, and to galaxies and all other objects outside the solar system from 1983 onwards. Presently there are about 1,400,000 references taken from 80,000 papers published in the 100 most important astronomical periodical publications. Articles are scanned in their entirety, and references to all objects mentioned are included in the bibliography. The scanning of the literature is made possible through a collaboration between Paris, Bordeaux and Strasbourg institutes, which has been recently described by Laloë et al.(1993).
A code is assigned to each considered paper (we call it a bibcode, in our jargon): this 19-digit bibcode contains enough information to locate the article (including year of publication, journal, volume, page, etc.). The structure of this code has been defined in close collaboration with the NED group at JPL/IPAC so that both databases apply the same coding system.
When one retrieves the bibliography of a SIMBAD object, a list of bibcodes is given, and (according to the options used) these bibcodes are automatically matched against a bibliographic file which provides for each citation the full reference, title and list of authors.
Up to now, SIMBAD did not include the abstracts of referenced papers. This situation is now changing rapidly.
An important step, for the CDS, was the creation of an abstract service for Astronomy & Astrophysics (main journal and Supplement Series) announced in A&A, 284, E1 (April 1994). This service is made available as part of the CDS World Wide Web server (Egret and Ochsenbein, 1994), and complements the service already existing for on-line tables of recent papers (Ochsenbein, 1993).
A similar agreement has recently be implemented with the Publications of the Astronomical Society of the Pacific (PASP) for which the abstracts since January 1994 are available.
Using the client/server approach, and the bibcode as the index key, it becomes now possible to retrieve the abstract of a recent A&A paper referenced in SIMBAD. This is done in the SIMBAD command line interface by typing the command abstract followed by a bibcode, for instance:
abstract 1994A&AS..103..135AWith X-SIMBAD, the procedure is to select (with cursor and mouse) the corresponding bibcode, and choose the Display/bibliography/abstract menu item.
Another important source of abstracts is the NASA/STI service (also distributed by ESA in Europe): the subset related to astronomy and astrophysics, is now available from the ADS and ESIS information systems, through sophisticated access modes (Kurtz, 1993; Giommi and Ansari, 1993). The interesting aspect for SIMBAD users, is that both groups include the SIMBAD bibliographical index as part of their file: this means that the SIMBAD bibcode can now in principle be used to retrieve the corresponding abstract as produced by NASA/STI (this is not the original abstract for copyright reasons).
Prototype implementations have shown that it is feasible, using the client/server approach, to complement the result of a SIMBAD query, with a query to an external server providing the relevant abstract. The overall solution is not only technical (client/server approach, use of the huge potentiality of the WorldWideWeb), but also political (this implies agreements between centers or agencies having converging interests), and operational (this has to rely on efficient but sometimes overloaded networks). At the time when this paper is written, these new functionalities are in a prototype phase: the users will be kept informed of the final implementation of these new features.
The X-SIMBAD interface has been developed by Isabelle Quatrehomme (software engineer), Daniel Egret, and Marc Wenger, together with the whole SIMBAD team (and especially Françoise Genova, whose numerous comments have been taken into account). Several groups of beta-testers have accepted to try the system in the early stages: thanks to all for their contributions !
The abstract service is maintained by François Ochsenbein, with the help of Patricia Bauer and Daniel Egret.
If you do not have your personal account on SIMBAD yet, please address a request to the Director of the CDS, or by electronic mail to firstname.lastname@example.org.