The English description of CATS

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The English description of CATS CATS database - Astrophysical CATalogs support System [ CATS home ] [ Back to CATS list ] The description of CATS data base Introduction and short description of CATS database Last update 29.09.98 by S. Trushkin. The ever growing rate of research papers published in astronomy has made manual bibliographic searches a prohibitive effort. The identification of the radio sources with other catalogs are especially hard work. Since several years on-line databases SIMBAD (at the Astronomical Data Center Strasbourg, CDS) and the "NASA/IPAC Extragalactic Database" NED "NASA/IPAC Extragalactic Database" (USA, Pasadena), and the "Lyon-Meudon Extragalactic Database" LEDA, Lyon provide astronomers the main (free!) source of information retrieval on astronomical objects. While these databases are reasonably complete for information on stars and galaxies, we felt the need to provide access to the overwhelming amount of radio source catalogues and tables with all their data columns. The CATS database you are accessing now was created initially as a system to support the RATAN-600 observations. Now with world-wide Internet access we hope that such a system will be useful for the entire astronomical community. The large majority of over THREE million different radio sources catalogued by now have not been optically identified and their nature is largely unknown. The classic example is the source 4C+04.66 known from 60ies. Only in 1978 it was identified with the famous X-ray and optical binary, and probable black hole, SS433. In the "CATS wall" below we list (by their short names) only a few of the well-known catalogues now available through CATS. But these acronyms sound familiar as the names of old friends. Clicking the ``mouse'' on one of these catalogues, will display the documentation for this survey. In Russia the group of the A. Gubanov of St.-Petersburg State University's Astronomical Institute (SPbU AI) has accumulated published data on radio emission from sources towards clusters of galaxies. These data are being integrated in the database of clusters of galaxies that will be supplied and will be accessible via Internet. This group has already prepared the database of Radio astronomical catalogues RAC . available on-line on the Internet. Collection of data We would like to mention the invaluable help from Dr. H. Andernach, who provided numerous catalogues by mutual agreement. Andernach's list (ver. Apr 1999) contains near 600 radio catalogs or tables and in addition lists over 500 catalogs or tables in other, non-radio bands . See the most last version of Andernach's list [ftp] The list of CATS' catalogs provides references and prepared documentation. In Mar 1999 this list gives ~280 references Total number of subdirectories is ~200 Search programs work with ~200 tables CATS list of catalogs . Structure of data The philosophy of CATS is shortly described in (Trushkin et al., 1996, Verkhodanov et al., 1997). Here we show some details. The politics of including the catalogs in CATS are based on three principles: to include all radio catalogs, based on radio surveys; to include most of non-stellar catalogs of objects; to include most of non-radio catalogs, using radio data; We constructed our database in the UNIX operating system without involving any standard data base systems for two main reasons: (a) they are very expensive commercial products; (b) there are no human resources to develop them in observatory. Therefore we designed our database using simple principles, permitting us to update it with new information easily: every new catalog of objects has to be contained in the UNIX directory having the same name as the catalog of objects; the description of the catalog must also be in that directory; the programs for local operations (programs of low level) with the catalog of objects are also in the same directory; brief characteristics and names of the programs and file with the description of the catalog are stored in the file cats_descr; there are scripts (programs of high level) operating with every low level program and documentaion of each catalog, and accessible from the UNIX standard shells, graphics and WWW system. The catalog description file (cats_descr) contains the name and type of the catalog (radio, optical, mixed, etc.), frequency range, minimum fluxes or magnitudes, type of coordinates (equatorial or/and galactic), names of the local programs for the select and match functions (both designed in "C" programming language), name of the document file, number of records in the catalog, resolution, calibration factor to rescale them to a common scale of flux densities, and the reference. To simplify the design of CATS operating programs, two utilities named 'select' and 'match' are provided. These utilities operate with a pattern string, describing a format of the ASCII table with astrophysical data. A user operates with CATS from any directory since the programs for general use of the catalogs are accessible system-wide. The described manner of catalog storage eases the database development, its expansion with new data and the fine-tuning of the supporting programs. All astronomical catalogs have a different format and list different observables. It has been a major challenge to provide uniform access to such a heterogeneous collection of data sets based on different methods, using different notations and units (in the absence of a ``standard'' to create catalogs). To satisfy the different needs of users we provide the result of searches through ALL catalogs in two different ways: one is an ordered table with the same basic data from the various catalogues in a homogenized format, while the other provides the result in the native format of each catalogue, listing all the orginally published data columns. CATS is (and will) capable to accomplish the following tasks: Provide a short description and characteristics of each catalog; print the full list of catalogs relevant for a given sky area. Select objects from one or several catalogs matching user-specified criteria, like equatorial and galactic coordinates, flux densities and spectral indices, observing frequency, names of catalogs unified in mixed catalogs and object type (if provided by the catalog). Cross--identification of different catalogs and selection after calculation of spectral indices. Drawing radio spectra of selected sources in the PS- or GIF- files and JAVA-applets. In the first time in database work the graphic CGI-programs are created for plotting of the spectra of sources from : Kuhr'79/Kuhr'81, PKSCAT90, RC_COLD, Kallas & Reich (1980) и SNR. Below you can see examples of plotting of spectra 3C48 from Kuhr's catalog (1981) Access to CATS For increasing of the rate of access CATS database was placed in two mirror sites on Ultra Sparc station server and special CATS-server, worked in local net of RATAN and SAO. In both cases following procedures could be made: access to search system via telnet://cats@cats.sao.ru/ or telnet://cats@www.ratan.sao.ru; access to files of data and descriptions via ftp://ftp.sao.ru/pub/cats/ or ftp://www.ratan.sao.ru/ ; hypertext access: http://cats.sao.ru/ or http://www.ratan.sao.ru/~cats ; access to search system via e-amil with address: cats@sao.ru ; access to CATS and other common accesible files via email (details of work with file-server anybody could received, if send letter with one word help to: observ@ratan.sao.ru ; work on WEB-server (with ОS Linux) in local net of SAO. First and last procedures work with system of menu. The forms are used in WEB-access for input of the parameters of search. We recomend to use graphic brousers for X-Window and Windows: Mosaic, Netscape, Internet Explorer, while text brouser Lynx could be used also. Search CGI-programs have been wroten with Shell and C. New probe Java-applet was created for interactive plotting of the spectra of the Kuhr's catalog sources (A.S. Trushkina, SpbTU). The tasks for search in big area or big list of sources demand long time and we recomend to use the e-mail tasks. Below examples of commamds for search are given if the email access in CATS is used (details if you send letter without text to cats@sao.ru ): Example of letter-task for receiving of the sample of all radio sources with flux densities more 0.5 Jy in given area of sky (ra, dec) with output of results in FITS-files less 50 kb: mail -s "" cats@sao.ru cats select ra min=12:30 max=12:40:15. dec > 0 < 5' 46" catalogs r epoch=1950 flux > 0.5 out fits, size=50 cats end Example of letter-task for receiving of the results of search of the coordinate identifications with error box (x in RA; y in DEC): mail -s "" cats@sao.ru cats match catalogs a window box x=60" y=40' sources: s1 02:02:00 +31:23:16 1950 s2 02:23:10 00:03:00 1950 s3 21:26:33.9 -18:34:33.0 1950 cats end The next development of the search procedure became including of the fast index search: GLobal IMPlicit SEarch and its hypertext version: WebGlimpse (U. Manber at al.) Its common accessible system could very fastly find the references of the given sample (in our case: names of sources and catalogs, the first names of authors and so on) amongst majority of files and form the list of references in hypertext output-file for further work. WebGlimpse allows to expand the system of search not only inside the local file system of CATS, but amongst documentation in analogous servers in Internet. Using CATS Authors have not full information about external using of the database. The common statistics shows that the number of users grows and now it is more 1500 per month. We could note that both search tasks and CATS documentation, are used by external users of CATS. The authors carried out some big cross-identifications for search of the peculiar objects. See list in References. Thus, CATS became indeed the BASE for the forming and checking of new observing program with telescope of SAO. In final the created database become part of common infosystem of the RATAN-600 radio telescope, including the antenna work, remote observation, archives, data-processing and interpretation. Format of data description Another important thing needs a special discussed agreement is the standard format of output. We have used the FITS (flexible image transport system) TABLE format (Wells et al., 1981; Geisen & Harten, 1981) to describe data obtained from the CATS. The simplified FITS table format, which we used, consists of the header extension with keywords (not longer than 8 characters) and their values, describing the data, and data themself. Example of output header of CATS data. The authors are grateful to RFBR for support of this project under grant No 96-07-89075. Here you can get the CATS booklet file 0CATS_booklet.ps.gz or 4 pages at two a4-lists: booklet (page1) booklet (page2) References Verkhodanov O.V., Trushkin S.A. Active database of astrophysical catalogs at RATAN-600. Preprint SAO RAS No 106. P.66-74. Nizhnij Arkhyz. 1995. Trushkin S.A., Andernach H., Micol A., Gubanov A.G., Verkhodanov O.V., Titov V.B., Chernenkov V.N. Public Databases for Radio Astronomy: a joint venture between East and West. In Proc. of the Third International Workshop on "Advances in Databases and Information Systems". 1996, Sept.10-13. Moscow Engineering Physical Inst. Publishing, V.2, p. 37-41. Andernach H., Trushkin S.A., Gubanov A.G., Verkhodanov O.V., Titov V.B., Micol A. Preparing a public database of radio sources. Baltic Astronomy, 1997, V.6, No 2. P.259-262. Verkhodanov O.V., Trushkin S.A., Chernenkov V.N. CATS: a database system of astrophysical catalogues. Baltic Astronomy, 1997, V.6, No 2. P.275-278. Verkhodanov O.V., Trushkin S.A., Andernach H., Chernenkov V.N. 1997. The CATS database to operate with astrophysical catalogs. In "Astronomical Data Analysis Software and Systems VI", eds. G.Hunt and H.E.Payne. ASP Conference Series, V.125, P.322-325. Andernach H., Trushkin S. "Current Status of Radio Source Databases" (in Proc. "Observational Cosmology with the New Radio Surveys", eds. M. Bremer, N. Jackson & I. Perez-Fournon, Kluwer Acad. Press. ASSL vol. 226, p.67-68 (astro-ph/9703141). Verkhodanov O.V., Chernenkov V.N., Trushkin S.A. 1997. Furter advance in the CATS database operation. First year of WWW access. In Proc. of the First East-Europian Symposium on Advances in Databases and Information Systems (ADBIS'97). St.Petersburg University, September 2-5, 1997. Publishing "Nevsky Dialect". V.2, p. 73-77. Verkhodanov O.V., Kononov V.K., Trushkin S.A., Chernenkov V.N. System of description of galactic and extragalactic sources. XXVII radio asctronomical. conf., SPb. IAA RAS, 1997, v.1, 316-329. Trushkin S.A., Verkhodanov O.V. Priperties of objectsa of ITA-catalog, spectra and NVSS identifications XXVII radio asctronomical. conf., SPb. IAA RAS, 1997, v.1, 328-329. Verkhodanov O.V., Trushkin S.A. Cross-identifiation of Texas catalog at 365 МHz and three IRAS catalogs XXVII radio asctronomical. conf., SPb. IAA RAS, 1997, v.1, 332-334. Verkhodanov O.V., Chernenkov V.N., Trushkin S.A. System of search of the astrophysical information in CATS database. XXVII radio asctronomical. conf., SPb. IAA RAS, 1997, v.1, 324-325.