J/ApJS/181/110ivo://CDS.VizieR/J/ApJS/181/110doi:10.26093/cds/vizier.21810110CDSMuno M.P.Bauer F.E.Baganoff F.K.Bandyopadhyay R.M.Bower G.C.,Brandt W.N.Broos P.S.Cotera A.Eikenberry S.S.Garmire G.P.,Hyman S.D.Kassim N.E.Lang C.C.Lazio T.J.W.Law C.Mauerhan J.C.,Morris M.R.Nagata T.Nishiyama S.Park S.Ramirez S.V.Stolovy S.R.,Wijnands R.Wang Q.D.Wang Z.Yusef-Zadeh F.2017-06-27T06:38:30Z2013-04-03T08:28:02ZCDS support team

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

cds-question@unistra.frx-ray-sourcessurveysmilky-way-galaxyWe present a catalog of 9017 X-ray sources identified in Chandra observations of a 2{deg}x0.8{deg} field around the Galactic center. This enlarges the number of known X-ray sources in the region by a factor of 2.5. The catalog incorporates all of the ACIS-I observations as of 2007 August, which total 2.25Ms of exposure. At the distance to the Galactic center (8kpc), we are sensitive to sources with luminosities of 4x10^32^erg/s (0.5-8.0keV; 90% confidence) over an area of 1deg^2^, and up to an order of magnitude more sensitive in the deepest exposure (1.0Ms) around Sgr A*. The positions of 60% of our sources are accurate to <1" (95% confidence), and 20% have positions accurate to <0.5". We search for variable sources, and find that 3% exhibit flux variations within an observation, and 10% exhibit variations from observation-to-observation. We also find one source, CXOUGC J174622.7-285218, with a periodic 1745s signal (1.4% chance probability), which is probably a magnetically accreting cataclysmic variable. We compare the spatial distribution of X-ray sources to a model for the stellar distribution, and find 2.8{sigma} evidence for excesses in the numbers of X-ray sources in the region of recent star formation encompassed by the Arches, Quintuplet, and Galactic center star clusters. These excess sources are also seen in the luminosity distribution of the X-ray sources, which is flatter near the Arches and Quintuplet than elsewhere in the field. These excess point sources, along with a similar longitudinal asymmetry in the distribution of diffuse iron emission that has been reported by other authors, probably have their origin in the young stars that are prominent at l~0.1{deg}.2009ApJS..181..110Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJS/181/110CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toB/chandra : The Chandra Archive Log (CXC, 1999-)J/ApJ/721/1663 : Near-IR matches of X-ray sources in GC (DeWitt+, 2010)J/ApJ/703/30 : NIR counterparts to Chandra X-ray sources (Mauerhan+, 2009)J/ApJ/685/958 : Spitzer and Chandra sources in galactic center (Arendt+ 2008)J/ApJS/165/173 : Chandra sources in Galaxy central 150pc (Muno+, 2006)J/ApJ/613/1179 : X-ray sources in Galactic Center (Muno+, 2004)J/ApJ/589/225 : Chandra X-ray sources toward GC (Feigelson+, 2003)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJS/181/110https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJS/181/110http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJS/181/110https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJS/181/110https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJS/181/110http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJS/181/110GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJS/181/110/table1 (Observations of the central 2{deg}x0.8{deg} of the Galaxy)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/181/110/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/181/110/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/181/110/table1?GETtext/xml+votable180.050000true266.01026-29.874090.005555555555555556Cone search capability for table J/ApJS/181/110/catalog (Galactic center X-ray sources)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/181/110/catalog?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/181/110/catalog?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/181/110/catalog?GETtext/xml+votable180.050000true266.23813-28.961210.0055555555555555566/28825 28827 28828 28830 28831https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJS/181/110?format=asciiX-raydefaultJ/ApJS/181/110/table4Sources with long-term variabilityrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeq[1/8962] Source numbermeta.idintCXOGCIAU name (HHMMSS.s+DDMMSS)meta.id;meta.maincharLoc[f/gc] f = Foreground, gc = Galactic centermeta.codecharObsMinObservation ID with lowest measured fluxmeta.id;phot.flux;obsintm_ObsMin[ab] Composant of observation identifiermeta.code.multipcharFminMinimum fluxph.cm**-2.s**-1phot.flux;stat.minfloate_FminUncertainty on minimum flux (1 sigma)ph.cm**-2.s**-1stat.errorfloatObsMaxObservation ID with highest measured fluxmeta.id;phot.flux;obsintm_ObsMax[ab] Composant of observation identifiermeta.code.multipcharFmaxMaximum fluxph.cm**-2.s**-1phot.flux;stat.maxfloate_FmaxUncertainty on maximum flux (1 sigma)ph.cm**-2.s**-1stat.errorfloatRatioRatio of maximum to minimum fluxphot.flux;arith.ratiofloate_Ratio? Lower bound on Ratiostat.error;arith.ratiofloatnullableE_Ratio? Upper bound on Ratiostat.error;stat.maxfloatnullableJ/ApJS/181/110/table5Sources with short-term variabilityObsIDObservation in which variability was detectedobs.param;obsintrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeq[1/8961] Source numbermeta.idintCXOGCIAU name (HHMMSS.s+DDMMSS)meta.id;meta.maincharLoc[f/gc] f = Foreground, gc = Galactic centermeta.codecharm_ObsID[ab] Composant of observation identifiermeta.code.multipcharOdd[10/1000] Odd prior used in Bayesian Blocks analysis (1)stat.fit.paramintNbl[2/10] Number of blocks foundmeta.numberintDur[752/111856] Duration of the block with the highest fluxsphot.flux;meta.table;stat.maxintFmin[0/0.0021] Minimum fluxph.cm**-2.s**-1phot.flux;stat.minfloate_FminLower bound on minimum flux (1 sigma)ph.cm**-2.s**-1stat.errorfloatE_FminUpper bound on minimum flux (1 sigma)ph.cm**-2.s**-1stat.error;stat.maxfloatFmax[1e-06/0.0026] Maximum fluxph.cm**-2.s**-1phot.flux;stat.maxfloate_FmaxLower bound on maximum flux (1 sigma)ph.cm**-2.s**-1stat.errorfloatE_FmaxUpper bound on maximum flux (1 sigma)ph.cm**-2.s**-1stat.error;stat.maxfloatRatio[0.84/247.48] Ratio of maximum to minimum fluxphot.flux;arith.ratiofloate_Ratio? Uncertainty on Ratiostat.error;arith.ratiofloatnullableJ/ApJS/181/110/table1Observations of the central 2{deg}x0.8{deg} of the GalaxyrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintObsObservation datestime.epoch;obsnullableObsID[658/8567] Observation identifiermeta.id;obs.param;obsintm_ObsID[ab] Component of observation identifiermeta.code.multipcharTargetTarget namemeta.id;meta.mainchartExpExposure timekstime.duration;obs.exposurefloatRAJ2000Right Ascension in degrees (J2000)degpos.eq.ra;meta.mainDEJ2000Declination in degrees (J2000)degpos.eq.dec;meta.mainRollRoll angle of the satellitedeginstr.paramfloatNIR? number of 2MASS sources used (1)meta.numberintnullableNX? number of X-ray matches used (2)meta.numberintnullableSigma1{sigma} uncertainties on astrometry (3)arcsecstat.errorfloatJ/ApJS/181/110/catalogGalactic center X-ray sourcesl_Sct.net[<] Limit flag on 0.5-2.0keV net counts (9)meta.code.errorcharn_SeqSimbad column added by the CDSmeta.ref.urlcharSeq[1/9017] Source numbermeta.idintprimaryCXOGCIAU name (HHMMSS.s-DDMMSS)meta.id;meta.maincharRAJ2000Right Ascension in degrees (J2000)degpos.eq.ra;meta.mainDEJ2000Declination in degrees (J2000)degpos.eq.dec;meta.mainePosPositional uncertainty, error circles (95%)arcsecstat.errorfloatm[cdw] Method for deriving position (1)meta.notecharFieldField in which source was detected (2)obs.fieldcharBandBand in which source was detected (3)instr.bandpasscharOffsetOffset from aimpoint (4)arcminpos.angDistancefloatNobsNumber of observations covering sourcemeta.numberintExpLive time at source positionstime.durationintPSFFraction of PSF encompassed by source regioninstr.det.psf;obs.field;arith.ratiofloatEPSFEnergy at which PSF was estimatedkeVem.energyfloatRadMinMinimum radius of source extraction region (5)arcsecphys.angSize;srcfloatFSENSCompletness limit (50%) at source position (6)ph.cm**-2.s**-1phot.fluxdoubleFlagsQuality Flags and other information (7)meta.code.errorcharPKS? Log of probability that source and background spectrum are from the same distribution according to a KS test (8)stat.fit.goodnessfloatnullablef_PKS[i] i=Infinite valuemeta.codecharSct.totTotal counts 0.5-2.0keV in source regionctphot.count;em.X-rayintSct.bgBackground counts 0.5-2.0keV in source regionctphot.count;em.X-rayfloatSct.netNet counts 0.5-2.0keV in source regionctphot.count;em.X-raydoublee_Sct.net[-39/]? Lower uncertainty on 0.5-2.0keV net counts (90% confidence)ctstat.errorfloatnullableE_Sct.net? Upper uncertainty on 0.5-2.0keV net counts (90% confidence) (9)ctstat.error;stat.maxfloatnullableHct.totTotal counts 2-8keV in source regionctphot.count;em.X-rayintHct.bgBackground counts 2-8keV in source regionctphot.count;em.X-rayfloatl_Hct.net[<] Limit flag on 2-8keV net counts (9)meta.code.errorcharHct.netNet counts 2-8keV in source regionctphot.count;em.X-raydoublee_Hct.net[-39/]? Lower uncertainty on 2-8keV net counts (90% confidence)ctstat.errorfloatnullableE_Hct.net? Upper uncertainty on 2-8keV net counts (90% confidence) (9)ctstat.error;stat.maxfloatnullableSfluxPhoton flux 0.5-2.0keVph.cm**-2.s**-1phot.flux;em.X-raydoubleHfluxPhoton flux 2-8keVph.cm**-2.s**-1phot.flux;em.X-raydouble<E>Background-corrected mean observed photon energykeVem.energyfloatHR0[-1,1]? Soft color (10)phot.flux;arith.ratiofloatnullablee_HR0[0,2]? 90% Lower uncertainty on HR0 (10)stat.errorfloatnullableE_HR0[0,2]? 90% Upper uncertainty on HR0 (10)stat.error;stat.maxfloatnullableHR1[-1,1]? Medium color (10)phot.flux;arith.ratiofloatnullablee_HR1[0,4]? 90% Lower uncertainty on HR1 (10)stat.errorfloatnullableE_HR1[0,2]? 90% Upper uncertainty on HR1 (10)stat.error;stat.maxfloatnullableHR2[-1,1]? Hard color (10)phot.flux;arith.ratiofloatnullablee_HR2[0,2]? 90% Lower uncertainty on HR2 (10)stat.errorfloatnullableE_HR2[0,2]? 90% Upper uncertainty on HR2 (10)stat.error;stat.maxfloatnullable