RASS/HRC ivo://nasa.heasarc/hrasscat NASA/GSFC HEASARC Zickgraf et al. 2026-10-02 NASA/GSFC HEASARC help desk heasarc-vo at athena.gsfc.nasa.gov Survey Source This table is a representation of part of the Hamburg/ROSAT All-Sky Survey (RASS) Catalog (HRC) of optical identifications of X-ray sources at high-galactic latitude, namely the list of X-ray sources. (The list of proposed and possible optical counterparts is given in the linked Browse table HRASSOPTID). The HRC includes all X-ray sources from the ROSAT Bright Source Catalog (RASS-BSC) with galactic latitude |b| >= 30 degrees and declination Dec >= 0 degrees. In this part of the sky covering ~10,000 square degrees, the RASS-BSC contains 5341 X-ray sources. For the optical identification, the HRC authors used blue Schmidt prism and direct plates taken for the northern hemisphere Hamburg Quasar Survey (HQS) which are now available in digitized form. The limiting magnitudes are 18.5 and 20, respectively. For 82% of the selected RASS-BSC, an identification could be given. For the rest, either no counterpart was visible in the error circle, or a plausible identification was not possible. With ~42%, AGN represent the largest group of X-ray emitters, ~31% have a stellar counterpart, whereas galaxies and cluster of galaxies comprise only ~4% and ~5%, respectively. In ~3% of the RASS-BSC sources, no object was visible on the blue direct plates within 40" around the X-ray source position. The catalog has been used as a source for the selection of (nearly) complete samples of the various classes of X-ray emitters. This table was produced by the HEASARC in February 2005 based on the CDS Catalog table J/A+A/406/353/x-ray.dat. This is a service provided by NASA HEASARC . 2003A&A...406..535Z https://heasarc.gsfc.nasa.gov/W3Browse/all/hrasscat.html Catalog Research served-by HEASARC TAP https://heasarc.gsfc.nasa.gov/xamin/vo/cone?showoffsets&table=hrasscat& GET text/xml 180 99999 true 33.2275 0.00416667 0.0333333333333333 https://heasarc.gsfc.nasa.gov/xamin/vo/tap https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/getvotable.pl?name=hrasscat GET text/xml https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/w3query.pl?tablehead=name=heasarc_hrasscat&Action=More+Options&Action=Parameter+Search&ConeAdd=1 ROSAT 0.0333333333333333 X-ray public hrasscat Hamburg/RASS Catalog: X-Ray Sources name Catalog Designation meta.id;meta.main char nullable ra Right Ascension degree pos.eq.ra;meta.main double nullable dec Declination degree pos.eq.dec;meta.main double nullable count_rate RASS Count Rate (counts/s) ct/s phot.count;em.X-ray double nullable count_rate_error Error in Count Rate (counts/s) ct/s stat.error;phot.count;em.X-ray double nullable "__x_ra_dec" System unit vector column double nullable "__y_ra_dec" System unit vector column double nullable "__z_ra_dec" System unit vector column double nullable "__row" System index column char nullable source_extent Source Extension (arcsec) arcsec phys.angSize short nullable extent_likelihood Source Extension Likelihood stat.likelihood;phys.angSize short nullable hardness_ratio_1_error Error in HR1 stat.error;phot.count;arith.ratio double nullable change_date Date of Last Change mjd int nullable lii Galactic Longitude degree pos.galactic.lon double nullable bii Galactic Latitude degree pos.galactic.lat double nullable flag_id Flag Indicates Identification Changed Since Last Catalog Version short nullable flag_edit Flag Indicates X-Ray Position Changed Since Last Catalog Version short nullable hardness_ratio_2_error Error in HR2 stat.error;phot.count;arith.ratio double nullable hardness_ratio_2 Hardness Ratio HR2 phot.count;arith.ratio double nullable id_code Code Indicates Type of Source Identification src.class short nullable flag_xray Flag Indicates Supplementary X-Ray Positions short nullable alt_name RASS Designation, RX JHHMM.m+DDMM, As Used in the First Catalog Version meta.id char nullable hardness_ratio_1 Hardness Ratio HR1 phot.count;arith.ratio double nullable error_radius Error Radius Derived from the ROSAT Bright Source Catalog (arcsec) arcsec stat.error;pos short nullable sequence_number Internal Number of the HRC Data Base meta.id char nullable