J/ApJ/450/51ivo://CDS.VizieR/J/ApJ/450/51doi:10.26093/cds/vizier.14500051CDSGreen P.J.Schartel N.Anderson S.F.Hewett P.C.,Foltz C.B.Brinkmann W.Fink H.Trumper J.Margon B.1999-03-02T09:13:38Z1999-03-02T10:13:24ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frquasarsx-ray-sourcesOf the more than 1000 QSOs in the Large Bright Quasar Survey (LBQS), we study the X-ray properties of 908 that were covered by the ROSAT All-Sky Survey (RASS). These data constitute among the largest, most homogeneous X-ray surveys of QSOs to date, and as such are well suited to the study of the multiwavelength properties of QSOs. Due to the ~600 s RASS exposure times, only 10% of the QSOs are detected in X-rays. However, by stacking X-ray counts, we obtain effectively much more sensitive observations for an average QSO in bins of redshift or luminosity, and for several classes of QSOs. We confirm a correlation of alpha_ox (slope of a hypothetical power law connecting 2500A and 2keV) with luminosity for the overall sample. For higher redshifts and optical luminosities, radio-loud QSOs appear to become progressively more luminous in X-rays than radio-quiet QSOs. The X-ray properties of a subsample of 36 broad absorption line QSOs suggest that they are strongly absorbed or underluminous in the X-rays, while a subsample of 22 Fe II-strong QSOs is anomalously X-ray bright.1995ApJ...450...51Ghttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/450/51CatalogResearchIsServedByTAP VizieR generic servicerelated-toIX/10 : ROSAT All-Sky Bright Source Catalogue (RASS) (Voges+ 1996)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/450/51https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/450/51http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/450/51https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/450/51https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/450/51http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/450/51GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapROSATX-raydefaultJ/ApJ/450/51/table1Raw data and luminosities of detected LBQS/RASS QSOsNameName of the LBQS QSOmeta.id;meta.maincharzRedshiftsrc.redshiftfloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBJmagB_J magnitudemagphot.mag;em.opt.BfloatA(B)Extinctionmagphys.absorptionfloatNHGalactic hydrogen column density1e+20cm**-2phys.columnDensityfloatCsrcRASS source countsphot.count;em.X-rayfloate_CsrcCsrc uncertaintystat.errorfloatCbkgRASS source counts normalized to the source aperture areaphot.count;em.X-rayfloate_CbkgCBkg uncertaintystat.errorfloatExpTimeRASS exposure timestime.duration;obs.exposurefloatl_log(LX)Lx limiting charactermeta.code.errorcharlog(LX)Logarithm of X-ray luminositylog(1e-07W)phys.luminosity;em.X-rayfloatlog(Lopt)Logarithm of optical luminositylog(1e-07W)phys.luminosityfloatl_Alp(oX)Alp(oX) limiting charactermeta.code.errorcharAlp(oX)Slope of a hypothetical power law connecting 250nm and 2 keVstat.fit.paramfloatNotesNotesmeta.notechar