J/A+AS/132/341ivo://CDS.VizieR/J/A+AS/132/341CDSMotch C.Guillout P.Haberl F.Krautter J.Pakull M.W.Pietsh W.,Reinsch K.Voges W.Zickgraf F.-J.1998-11-26T13:53:07Z1998-11-26T14:51:42ZCDS support team

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

cds-question@unistra.frx-ray-sourcesastronomical-object-identificationWe report on optical searches in the error circles of 93 ROSAT survey sources located at low galactic latitudes (|b|<20{deg}). These sources were extracted from the ROSAT Galactic Plane Survey using various selection criteria on hardness ratio, X-ray and optical brightness and integrated galactic absorption in the direction of the source. We find optical identifications in 76 cases, among which are 25 new AGN, 6 new CVs and a new Be/X-ray binary. In order to illustrate the relevance of the source selections applied here, we cross-correlated the ROSAT all-sky survey bright source list with SIMBAD. Different classes of X-ray emitters populate distinct regions of a multi dimensional parameter space involving flux ratios, galactic latitude and N_H_. This relatively good segregation offers the possibility to build source samples with enhanced probability of identification with a given class. Complete optical identification of such subsamples could eventually be used to compute meaningful probabilities of identification for all sources using as basis a restricted set of multi-wavelength information.1998A&AS..132..341Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+AS/132/341CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toIX/10 : ROSAT All-Sky Bright Source Catalogue (1RXS) (Voges+ 1996)J/A+A/318/111 : ROSAT Galactic Plane Survey (Motch+ 1997)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+AS/132/341https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+AS/132/341http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+AS/132/341https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+AS/132/341https://vizier.iucaa.in/viz-bin/votable?-source=J/A+AS/132/341http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+AS/132/341GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+AS/132/341/table4 (X-ray characteristics of ROSAT survey sources derived from the SASS as in October 1991)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+AS/132/341/table4?https://vizier.iucaa.in/viz-bin/conesearch/J/A+AS/132/341/table4?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+AS/132/341/table4?GETtext/xml+votable180.050000true8.96916759.8355560.005555555555555556Cone search capability for table J/A+AS/132/341/table5 (Optical identifications of ROSAT survey sources)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+AS/132/341/table5?https://vizier.iucaa.in/viz-bin/conesearch/J/A+AS/132/341/table5?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+AS/132/341/table5?GETtext/xml+votable180.050000trueROSAThttps://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+AS/132/341?format=asciiX-raydefaultJ/A+AS/132/341/table4X-ray characteristics of ROSAT survey sources derived from the SASS as in October 1991HR1Hard ratio 1phot.flux;arith.ratiofloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRXJSource namemeta.id;meta.maincharprimarySource[XAOBS] Source selection origin (1)meta.notecharRA2000Right ascension (2000.0)pos.eq.ra;meta.mainDE2000Declination (2000.0)pos.eq.dec;meta.mainr90? 90% confidence radiusarcsecstat.errorfloatnullableCountCount ratect/sphot.count;em.X-rayfloate_Countrms uncertainty on Countct/sstat.errorfloate_HR1? rms uncertainty on HR1stat.errorfloatnullableHR2Hard ratio 2phot.flux;arith.ratiofloate_HR2? rms uncertainty on HR2stat.errorfloatnullable1RXS1RXS (Cat. <IX/10>) designationmeta.idcharJ/A+AS/132/341/table5Optical identifications of ROSAT survey sourcesRXJSource namemeta.id;meta.maincharprimaryrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSel[XAOBS] Source selection origin (1)meta.notecharDist? X-ray to optical distance in units of the 90% confidence radiuspos.angDistancefloatnullableRA2000? Right ascension (2000.0)pos.eq.ra;meta.mainnullableDE2000? Declination (2000.0)pos.eq.dec;meta.mainnullableIdOptOptical identificationmeta.idcharVmag? V magnitudemagphot.mag;em.opt.VfloatnullableBmag? B magnitudemagphot.mag;em.opt.BfloatnullableClassClass (2)src.classcharMtypeSpectral or morphological typesrc.morph.typecharChart[Y] Y: a finding chart is providedobs.fieldchar