This table comprises the Sternberg Astronomical Institute (SAI) Catalog of Supernovae. This version contains data on 2991 extragalactic supernovae (SNe) which were discovered from 1885 until December 12, 2004 and on their host galaxies. Data for host galaxies were compiled from the following catalogues: (1) RC3 (de Vaucouleurs et al. 1991, Cat. ); (2) UGC (Nilson 1973. Cat. ); (3) PGC (Paturel et al. 1989, Cat. ); (4) MCG (Vorontsov-Velyaminov et al. 1962-1968, Cat. , ); (5) ESO (Lauberts 1982, Cat. ); (6) CfA (Huchra et al. 1994, see Cat ), and (7) from van den Bergh (1994, Cat. ). The main source of morphological types, major diameters and axial ratios was the RC3; the data from other sources were reduced to the system of RC3. Photographic magnitudes of galaxies were adopted from the UGC and the PGC together with individual data from the literature. The sources of recession velocities or cz values were the RC3, the CfA, the PGC and IAU Circulars. Position angles were taken from the RC3, UGC and the ESO catalogues, and inclination angles were mainly derived from data in RC3 according to Holmberg (1958MeLu2.136....1H). Some data for SNe and host galaxies were adopted from the GCVS (Samus et al. 1995, Cat. ). This table was created by the HEASARC in June 2005 based on CDS table II/256/sn.dat. Notice that the number of entries (2991) is more than the number of 2780 mentioned in the published reference: this is apparently due to the fact that the CDS table contains supernovae as recent as December 12, 2004, while the latter is complete only until January 6, 2004. This is a service provided by NASA HEASARC .

This catalog presents X-ray data for all entries in the Third Catalogue of Nearby Stars (CNS3: Gliese and Jahreiss, 1991, ADC/CDS Cat. ) that have been detected as X-ray sources in the ROSAT All-Sky Survey (RASS). The catalog contains 1252 entries, yielding an average detection rate of 32.9 percent of the 3802 CNS3 stars. In addition to count rates, source detection parameters, X-ray hardness ratios, and X-ray fluxes, X-ray luminosities derived from Hipparcos parallaxes are also listed. For a star to have been considered by the authors to have been detected as an X-ray source in the RASS, an X-ray source with an existence likelihood of 7 or more (equivalent to a source existence probablity of 99.9 percent or more) had to lie within 90 arcseconds of its 1990 epoch CNS3 position. The choice of this cut-off radius was based on a Monte Carlo simulation of about the same number of random positions that were used as input positions. At an offset of 90 arcseconds between the optical and X-ray positions the probability that the X-ray source is attributable to the star and not to a unrelated background object is 50 percent; this probability increases very rapidly for smaller values of the offset, notice. This database was created in June 1999 based on tables provided by the ADC/CDS data centers supplemented by additional tabular material provided to the HEASARC by the author Dr. M. Huensch. This is a service provided by NASA HEASARC .

A summary of spectroscopic identifications is presented for a complete sample of bright, soft, high galactic-latitude X-ray sources drawn from the ROSAT All-Sky Survey (RASS) which have PSPC count-rates CR>0.5cts/s, hardness ratios HR1<0, and galactic latitudes |b| > 20 degrees. Out of a total of 397 sources, 270 had previously catalogued counterparts, although most of these were not previously known as X-ray sources; of the remaining 127 sources neither X-ray nor optical properties were previously known. Of the whole sample of very soft X-ray sources 155 were also discovered by the Wide-Field-Camera on board ROSAT. Spectroscopic identifications are presented for 108 sources and other identifications for a further 18 sources; 1 source remains unidentified so far. In practically all cases a unique optical counterpart exists, facilitating identification. The largest source classes are AGN, magnetic cataclysmic variables, and hot white dwarfs This database was created by the HEASARC in April 1999 based on tables provided by the authors to CDS/ADC. This is a service provided by NASA HEASARC .

This table contains a catalog of 3405 X-ray sources from the ROSAT All Sky Survey (RASS) Bright Source Catalog which fall within the area covered by the 6dF Galaxy Survey (6dFGS). The catalog is count-rate limited at 0.05 ct s^-1 in the X-ray and covers the area of sky with Declination < 0 degrees and |b| > 10 degrees. The RASS-6dFGS sample was one of the additional target catalogs of the 6dFGS and as a result the authors obtained optical spectra for 2224 (65 per cent) RASS sources. Of these, 1715 (77%) have reliable redshifts with a median redshift of z = 0.16 (excluding the Galactic sources). For the optically bright sources (b_J <= 17.5) in the observed sample, over 90% have reliable redshifts. The catalog mainly comprises quasi-stellar objects (QSOs) and active galaxies but also includes 238 Galactic sources. Of the sources with reliable redshifts, the majority are type 1 active galactic nuclei (AGN, 69%), while 12% are type 2 AGN, 6% absorption-line galaxies and 13% are stars. The authors also identify a small number of optically faint, very low redshift, compact objects which fall outside the general trend in the b_J - z plane. The RASS-6dFGS catalog complements a number of Northern hemisphere samples, particularly the ROSAT Bright Source Catalogue-NRAO VLA Sky Survey (RBSC-NVSS) sample (Bauer et al. 2000, ApJS, 129, 547), and furthermore, in the same region of sky (-40 degrees < Declination < 0 degrees) reveals an additional 561 sources that were not identified as part of that sample. The authors detect 918 sources (27%) of the RASS-6dFGS sample in the radio using either the 1.4 GHz NVSS or the 843 MHz Sydney University Molonglo Sky Survey (SUMSS) catalogues and find that the detection rate changes with redshift. At redshifts larger than 1 virtually all of these sources have radio counterparts and with a median flux density of 1.15 Jy, they are much stronger than the median flux density of 28.6 mJy for the full sample. The authors attribute this to the fact that the X-ray flux of these objects is being boosted by a jet component, possibly Doppler boosted, that is only present in radio-loud AGN. The RASS-6dFGS sample provides a large set of homogeneous optical spectra ideal for future studies of X-ray emitting AGN. This table was created by the HEASARC in April 2010 based on an electronic version of Table 3 from the reference paper obtained from the MNRAS web site. This is a service provided by NASA HEASARC .

This table contains the catalog from the ROSAT All-Sky Survey (RASS) Center for Astrophysics (CfA) Loose Systems, or RASSCALS, the largest X-ray and optical survey of low-mass galaxy groups as of its publication date in 2000. The authors drew 260 groups from the combined Center for Astrophysics and Southern Sky Redshift Surveys, covering one-quarter of the sky to a limiting Zwicky magnitude of m_z = 15.5. They detected 61 groups (23%) as extended X-ray sources. The X-ray detections have a median membership of nine galaxies, a median recession velocity cz = 7250 km/s, a median projected velocity dispersion sigma(p) = 400 km/s, and a median X-ray luminosity L(x) = 3 x 10⁴² /h(100)² erg/s, where the Hubble constant is H(0) = 100 h(100) km/s/Mpc. The data in this table replace the preliminary analysis of the X-ray data which was presented in Mahdavi et al., 1999, ApJ, 518, 69 (CDS Cat. . This table was created by the HEASARC in September 2005 based on CDS tables J/ApJ/534/114/table2.dat & table3.dat. This is a service provided by NASA HEASARC .