J/ApJ/695/1094ivo://CDS.VizieR/J/ApJ/695/1094doi:10.26093/cds/vizier.16951094CDSPosson-Brown J.Raychaudhury S.Forman W.Donnelly R.H.Jones C.2018-01-31T06:09:53Z2011-05-10T11:54:45ZCDS support team

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

cds-question@unistra.frgalaxiesx-ray-binary-starsglobular-star-clustersphotometryWe present the X-ray point-source population in the nearby Virgo elliptical galaxy NGC 4636 from three Chandra X-ray observations. These observations, totaling ~193ks after time filtering, were taken with the Advanced CCD Imaging Camera (ACIS) over a three-year period. Using a wavelet decomposition detection algorithm, we detect 318 individual point sources. For our analysis, we use a subset of 277 detections with >=net 10 counts (a limiting luminosity of approximately 1.2x10^37^erg/s in the 0.5-2keV band, outside the central 1.5' bright galaxy core). We present a radial distribution of the point sources. Between 1.5' and 6' from the center, 25% of our sources are likely to be background sources (active galactic nuclei (AGNs)) and 75% are low-mass X-ray binaries (LMXBs) within the galaxy, while at radial distances greater than 6', background sources (AGN) will dominate the point sources. We find 77 matches between X-ray point sources and globular cluster (GC) candidates found in deep optical images of NGC 4636. In the annulus from 1.5' to 6' of the galaxy center, 48 of the 129 X-ray point sources (37%) with >=10 net counts are matched with GC candidates. Since we expect 25% of these sources to be background AGN, the percentage matched with GCs could be as high as 50%. Of these matched sources, we find that ~70% are associated with the redder GC candidates, those that are thought to have near-solar metal abundance.2009ApJ...695.1094Phttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/695/1094CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toB/chandra : The Chandra Archive Log (CXC, 1999-)J/ApJ/602/231 : Chandra X-ray point sources in nearby galaxies (Colbert+,J/A+A/433/43 : C-T1 phot. of NGC 4636 globular cluster system (Dirsch+, 2005)J/A+A/459/391 : Dynamics of NGC 4636 globular cluster system (Schuberth+,J/A+A/488/1221 : BMW-Chandra source catalog (Romano+, 2008)J/ApJS/192/10 : Chandra ACIS survey in 383 nearby galaxies. I. (Liu, 2011)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/695/1094https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/695/1094http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/695/1094https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/695/1094https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/695/1094http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/695/1094GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/695/1094/table2 (Summary of X-ray point sources detected in NGC 4636)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/695/1094/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/695/1094/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/695/1094/table2?GETtext/xml+votable180.050000true190.70772.68780.005555555555555556Cone search capability for table J/ApJ/695/1094/table3 (X-ray point sources matched with globular clusters candidates in NGC 4636)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/695/1094/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/695/1094/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/695/1094/table3?GETtext/xml+votable180.050000true190.70042.76460.0055555555555555566/26313 263162.762881831355591e-19 3.3785437584409506e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/695/1094?format=asciiOpticaldefaultJ/ApJ/695/1094/table2Summary of X-ray point sources detected in NGC 4636recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000Right Ascension in decimal degrees (J2000)degpos.eq.ra;meta.mainDEJ2000Declination in decimal degrees (J2000)degpos.eq.dec;meta.mainNctNet 0.5-2keV band countsctphot.count;em.X-rayintLumThe 0.5-2keV band luminosity in erg/s1e-07Wphys.luminosity;em.X-raydoubleHR1Soft color (1)phot.flux;arith.ratiofloatHR2Hard Color (2)phot.flux;arith.ratiofloatDistDistance of source from centerarcminpos.angDistancefloatInst[1/3] Instrument code (3)meta.code;instrintVarVariability code (4)meta.code;src.varcharGC? GC number in table 3meta.idintnullableJ/ApJ/695/1094/table3X-ray point sources matched with globular clusters candidates in NGC 4636recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintGCRunning identification number (<[PRF2009] NN> in Simbad)meta.id;meta.mainintprimaryRAXX-ray Right Ascension in decimal degrees (J2000)degpos.eq.ra;meta.mainDEXX-ray Declination in decimal degrees (J2000)degpos.eq.dec;meta.mainOffsetfrom NGC 4636 centerarcsecpos.angDistancefloatCTIODirsch et al. (2005, Cat. J/A+A/433/43) CTIO identification numbermeta.id.crossintRAOdegOptical Right Ascension in decimal degrees (J2000)degpos.eq.raDEOdegOptical Declination in decimal degrees (J2000)degpos.eq.decdoubleC-RThe (C-R) color index (Washington C (blue) minus Kron-Cousins R)magphot.color;em.opt.B;em.opt.RfloatRmagThe Kron-Cousins R band magnitudemagphot.mag;em.opt.Rfloat