RASS/Giant ivo://nasa.heasarc/rassgiant NASA/GSFC HEASARC Huensch, Schmitt, Voges 2026-04-03 NASA/GSFC HEASARC help desk heasarc-vo at athena.gsfc.nasa.gov Star The ROSAT All-Sky Survey Catalogue of Optically Bright Late-Type Giant and Supergiant Stars contains X-ray data for all late-type (spectral types of A through M, inclusive) giants and supergiants (luminosity classes of I through III-IV, inclusive) listed in the Bright Star Catalogue (BSC) that have been detected in the ROSAT All-Sky Survey. The RASS giants and supergiants catalog contains 450 entries of X-ray emitting, evolved late-type stars, which corresponds to an average detection rate of 11.7 percent. For each star, the ROSAT PSPC count rate, the hardness ratio, the apparent X-ray flux (calculated using an individual energy-conversion-factor based on the hardness ratio), and the ratio of X-ray to bolometric flux are given. The full details of the data selection, the source detection criteria, etc., are given in the paper by Huensch, Schmitt and Voges (1998, A&AS, 127, 251) describing this catalog; essentially for a star to be identified as an X-ray source, the X-ray source had to have at least a 99.9 percent existence probability, corresponding to a likelihood of greater than or equal to 7, and lie within 90 arcseconds of the optical position. Given the number of sky locations examined and the total number of RASS sources, it is expected that of order 27.4 of the 450 claimed associations in this catalog will be chance coincidences. This database was created at the HEASARC in July 1998 based on the ADC/<a href="https://cdsarc.cds.unistra.fr/ftp/cats/J/A+AS/127/251">CDS Catalog J/A+AS/127/251</a>. This is a service provided by NASA HEASARC . 1998A&AS..127..251H https://heasarc.gsfc.nasa.gov/W3Browse/all/rassgiant.html Catalog Research served-by HEASARC TAP https://heasarc.gsfc.nasa.gov/xamin/vo/cone?showoffsets&table=rassgiant& GET text/xml 180 99999 true 24.3667 -84.7697 0.0333333333333333 https://heasarc.gsfc.nasa.gov/xamin/vo/tap https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/getvotable.pl?name=rassgiant GET text/xml https://heasarc.gsfc.nasa.gov/cgi-bin/W3Browse/w3query.pl?tablehead=name=heasarc_rassgiant&Action=More+Options&Action=Parameter+Search&ConeAdd=1 STAR CATALOG 0.0333333333333333 X-ray public rassgiant ROSAT All-Sky Survey: Giants & Supergiants dec Declination degree pos.eq.dec;meta.main double nullable count_rate Mean PSPC Count Rate phot.count;em.X-ray double nullable hr Bright Star Number meta.id;meta.main int nullable log_xray_bol X-ray to Bolometric Flux Ratio phot.flux;arith.ratio;em.X-ray;em.opt float nullable "__y_ra_dec" System unit vector column double nullable "__z_ra_dec" System unit vector column double nullable hardness_ratio_error Hardness Ratio Error stat.error;phot.count;arith.ratio;em.X-ray.soft float nullable exposure_time Effective Exposure Time s time.duration;obs.exposure int nullable bii Galactic Latitude degree pos.galactic.lat double nullable vmag V Magnitude phot.mag;em.opt.V float nullable off_set Offset between Optical and X-ray Position arcsec pos.angDistance short nullable "__row" System index column char nullable ra Right Ascension degree pos.eq.ra;meta.main double nullable bv_color B-V Color Index phot.color;em.opt.B;em.opt.V float nullable binary_flag Binary Flag meta.code char nullable hardness_ratio Hardness Ratio phot.count;arith.ratio;em.X-ray.soft float nullable flux Apparent X-ray Flux phot.flux;em.X-ray double nullable lii Galactic Longitude degree pos.galactic.lon double nullable name Object Designation meta.id char nullable spect_type MK Spectral Classification src.spType char nullable likelihood Likelihood of Existence stat.likelihood int nullable hd Henry Draper Number meta.id int nullable class Browse Object Classification src.class int nullable "__x_ra_dec" System unit vector column double nullable count_rate_error PSPC Count Rate Error stat.error;phot.count;em.X-ray float nullable