J/AN/319/201ivo://CDS.VizieR/J/AN/319/201doi:10.26093/cds/vizier.113190201CDSProsser C.F.Randich S2025-09-29T20:17:10Z2000-02-21T22:49:12ZCDS support team

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

cds-question@unistra.fropen-star-clustersphotometryx-ray-sourcesspectroscopyFollowing the work of Randich et al. (1996A&A...305..785R) involving a ROSAT raster scan survey of the {alpha} Persei open cluster, we present here the results of a photometric/spectroscopic program examining the possible optical counterparts to a group of 73 X-ray sources in the raster survey which were not matched to catalogued stars. Of the 73 sources investigated, ~40 have an optical counterpart with photometry acceptable for cluster membership and ~20 of these also have radial velocities consistent with membership. We discuss the X-ray properties of these potential new members and why they may not have been identified in earlier membership surveys of this cluster.1998AN....319..201Phttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AN/319/201CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toI/68 : Positions and Proper Motions in alpha Per cluster (Fresneau, 1980)J/AN/319/315 : Alpha Per cluster low-mass members. II. (Prosser+, 1998)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AN/319/201https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AN/319/201http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AN/319/201https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AN/319/201https://vizier.iucaa.in/viz-bin/votable?-source=J/AN/319/201http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AN/319/201GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/AN/319/201/table1 (Raster APX X-ray source list)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AN/319/201/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/AN/319/201/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AN/319/201/table1?GETtext/xml+votable180.050000true50.2249.4647220.005555555555555556Cone search capability for table J/AN/319/201/table2 (Optical counterparts)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AN/319/201/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/AN/319/201/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AN/319/201/table2?GETtext/xml+votable180.050000true50.21458349.4663890.0055555555555555565/442 6/1725 1727 1763 3093 3095 3136-3138https://cdsarc.cds.unistra.fr/viz-bin/moc/J/AN/319/201?format=asciiX-rayOpticaldefaultJ/AN/319/201/table1Raster APX X-ray source listrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintAPX[1/73] APX numbermeta.id;meta.mainintprimaryRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainMLhHardband Maximum Likelihood valuestat.likelihoodfloatExpTimeEffective exposure timestime.duration;obs.exposureintCountRateCount rates**-1phot.count;em.X-rayfloate_CountRaterms uncertainty on CountRates**-1stat.error;phot.countfloatl_HRLimit flag on HRmeta.code.errorcharHRHardness ratio (1)phot.flux;arith.ratiofloatJ/AN/319/201/table2Optical counterpartsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintAPX[1/73] APX numbermeta.id;meta.mainintprimaryStarStar name (1)meta.idcharn_Star[ab] Note detailed in notes.dat (2)meta.notecharRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainVmagV magnitudemagphot.mag;em.opt.VfloatB-V? B-V colour indexmagphot.color;em.opt.B;em.opt.Vfloatnullableu_B-VUncertainty flag on B-Vmeta.code.error;phot.color;em.opt.BcharV-Ik? (V-I)_K_ colour indexmagphot.colorfloatnullableo_Vmag? Number of observation in V bandmeta.numberintnullableo_Bmag? Number of observation in B bandmeta.numberintnullableo_Imag? Number of observation in I bandmeta.numberintnullableB-V0? (B-V)_0_ colour indexmagphot.color;em.opt.B;em.opt.Vfloatnullablelog(LX)? X-ray luminositylog(solLum)phys.luminosity;em.X-rayfloatnullablelog(Lbol)? Bolometric luminositylog(solLum)phys.luminosityfloatnullablelog(LX/Lbol)? X-ray to bolometric luminosity ratiophys.luminosity;arith.ratiofloatnullableHaMemb[YN ?] H{alpha} member flagmeta.notecharHalpha[YN] H{alpha} emission flagmeta.code.errorcharEWHa? H{alpha} equivalent width0.1nmspect.line.eqWidth;em.line.HalphafloatnullableRV1? Radial velocity for brighter stars, based on H{alpha} observationskm/sspect.dopplerVelocintnullableRV2? Radial velocity for other stars, based on echelle observationskm/sspect.dopplerVelocintnullablel_vsiniLimit flag on vsinimeta.code.error;phys.veloc.rotatcharvsini? Rotational velocity for brighter stars, based on echelle observationskm/sphys.veloc.rotatintnullableu_vsiniUncertainty flag on vsinimeta.code.error;phys.veloc.rotatcharMemRV[YN ?] Membership from radial velocitymeta.code.membercharMem[YN ?] Final membershipmeta.code.member;phys.atmol.finalcharJ/AN/319/201/notesIndividual notes on finding charts (Appendix A)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintAPXAPX Numbermeta.id;meta.mainintm_APXMultiplicity indexmeta.code.multipcharNoteText of the notemeta.notechar