J/MNRAS/479/2834ivo://CDS.VizieR/J/MNRAS/479/2834doi:10.26093/cds/vizier.74792834CDSHenleywillis S.Cool A.M.Haggard D.Heinke C.Callanan P.Zhao Y.2024-08-18T20:20:36Z2019-03-15T12:28:54ZCDS support team

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

cds-question@unistra.frglobular-star-clustersx-ray-sourcesWe identify 233 X-ray sources, of which 95 are new, in a 222ks exposure of omega Centauri with the Chandra X-ray Observatory's Advanced CCD Imaging Spectrometer detector. The limiting unabsorbed flux in the core is fX(0.5-6.0keV)~=3x10^-16^erg/s/cm^2^ (Lx~=1x10^30^erg/s at 5.2kpc). We estimate that ~60+/-20 of these are cluster members, of which ~30 lie within the core (r_c_=155-arcsec), and another ~30 between 1-2 core radii. We identify four new optical counterparts, for a total of 45 likely identifications. Probable cluster members include 18 cataclysmic variables (CVs) and CV candidates, one quiescent low-mass X-ray binary, four variable stars, and five stars that are either associated with omega Cen's anomalous red giant branch or are sub-subgiants. We estimate that the cluster contains 40+/-10 CVs with Lx>10^31^erg/s, confirming that CVs are underabundant in omega Cen relative to the field. Intrinsic absorption is required to fit X-ray spectra of six of the nine brightest CVs, suggesting magnetic CVs, or high-inclination systems. Though no radio millisecond pulsars (MSPs) are currently known in omega Cen, more than 30 unidentified sources have luminosities and X-ray colours like those of MSPs found in other globular clusters; these could be responsible for the Fermi-detected gamma-ray emission from the cluster. Finally, we identify a CH star as the counterpart to the second brightest X-ray source in the cluster and argue that it is a symbiotic star. This is the first such giant/white dwarf binary to be identified in a globular cluster.2018MNRAS.479.2834Hhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/479/2834CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/ApJ/697/224 : Chandra X-ray sources in {omega} Cen (Haggard+, 2009)J/A+A/493/959 : UBV(RI)cHalpha photometry in omega Cen (Bellini+, 2009)J/ApJ/710/1032 : Proper motions in {omega} Cen (Anderson+, 2010)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/479/2834https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/479/2834http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/479/2834https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/479/2834https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/479/2834http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/479/2834GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/479/2834/table1 (Full set of 233 sources that appear in the 2012 data set, 95 of which are new)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/479/2834/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/479/2834/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/479/2834/table1?GETtext/xml+votable180.050000true201.67294167-47.475750.0055555555555555566/43225 43227https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/479/2834?format=asciiX-raydefaultJ/MNRAS/479/2834/table1Full set of 233 sources that appear in the 2012 data set, 95 of which are newSimbadNameSimbad column added by the CDSmeta.idcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameName from Haggard et al. (2009, Cat. J/ApJ/697/224, [HCD2009] NNNa in Simbad) or this workmeta.id;meta.maincharn_Name[*] * for names assigned in this workmeta.notecharRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainePos95% confidence error circle radius calculated using equation 5 of Hong et al. (2005ApJ...635..907H)arcsecstat.error;phys.angSizefloatOffsetOffset (1)pos;arith.difffloatXMdDetected medium (0.5-4.5keV) band X-ray countsctphot.count;em.X-rayintXMcCorrected medium (0.5-4.5keV) band X-ray countsctphot.count;em.X-rayfloatXSdDetected soft (0.5-1.5keV) band X-ray countsctphot.count;em.X-rayintXScCorrected soft (0.5-1.5keV) band X-ray countsctphot.count;em.X-rayfloatXHdDetected hard (1.5-6.0keV) band X-ray countsctphot.count;em.X-rayintXHcCorrected hard (1.5-6.0keV) band X-ray countsctphot.count;em.X-rayfloatlog(XS/XH)? Soft-to-hard X-ray count ratiophot.count;arith.ratiofloatnullableFXMMedium (0.5-4.5keV) band X-ray flux1e-19W.m**-2phot.flux;em.X-rayfloatFXTTotal (0.5-6.0keV) band X-ray flux1e-19W.m**-2phot.flux;em.X-rayfloatFXSSoft ((0.5-2.0keV) band X-ray flux1e-19W.m**-2phot.flux;em.X-rayfloatFXratio? 2012/2000 0.5-6.0keV band flux ratio (2)phot.flux;arith.ratiofloatnullablen_FXratio[g] Note on FXratio (3)meta.notecharOIDOptical ID (4)meta.notechar