J/ApJ/816/38ivo://CDS.VizieR/J/ApJ/816/38doi:10.26093/cds/vizier.18160038CDSTomsick J.A.Krivonos R.Wang Q.Bodaghee A.Chaty S.Rahoui F.,Rodriguez J.Fornasini F.M.2017-01-23T22:00:00Z2016-04-22T13:38:43ZCDS support team

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

cds-question@unistra.frx-ray-sourcesgamma-ray-astronomyWe report on 0.3-10keV observations with the Chandra X-ray Observatory of eight hard X-ray sources discovered within 8{deg} of the Galactic plane by the International Gamma-ray Astrophysics Laboratory (INTEGRAL) satellite. The short (~5ks) Chandra observations of the IGR source fields have yielded very likely identifications of X-ray counterparts for three of the IGR sources: IGRJ14091-6108, IGRJ18088-2741, and IGRJ18381-0924. The first two have very hard spectra in the Chandra band that can be described by a power law with photon indices of {Gamma}=0.6+/-0.4 and -0.7_-0.3_^+0.4^, respectively (90% confidence errors are given), and both have a unique near-IR counterpart consistent with the Chandra position. IGR J14091-6108 also displays a strong iron line and a relatively low X-ray luminosity, and we argue that the most likely source type is a cataclysmic variable (CV), although we do not completely rule out the possibility of a high mass X-ray binary. IGR J18088-2741 has an optical counterpart with a previously measured 6.84hr periodicity, which may be the binary orbital period. We also detect five cycles of a possible 800-950s period in the Chandra light curve, which may be the compact object spin period. We suggest that IGR J18088-2741 is also most likely a CV. For IGR J18381-0924, the spectrum is intrinsically softer with {Gamma}=1.5_-0.4_^+0.5^, and it is moderately absorbed, N_H_=(4+/-1)x10^22^/cm2. There are two near-IR sources consistent with the Chandra position, and they are both classified as galaxies, making it likely that IGR J18381-0924 is an active galactic nucleus. For the other five IGR sources, we provide lists of nearby Chandra sources, which may be used along with further observations to identify the correct counterparts, and we discuss the implications of the low inferred Chandra count rates for these five sources.2016ApJ...816...38Thttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/816/38CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toB/chandra : The Chandra Archive Log (CXC, 1999-2014)II/319 : UKIDSS-DR9 LAS, GCS and DXS Surveys (Lawrence+ 2012)VIII/76 : Leiden/Argentine/Bonn (LAB) Survey of Galactic HI (Kalberla+ 2005)J/A+A/562/A2 : 100-month Swift catalogue of SFXTs (Romano+, 2014)J/A+A/545/A27 : INTEGRAL/IBIS 9yr Galactic Hard X-Ray Survey (Krivonos+, 2012)J/ApJS/186/1 : The 4th IBIS/ISGRI soft gamma-ray survey catalog (Bird+, 2010)J/ApJ/701/811 : Chandra observations of INTEGRAL sources (Tomsick+, 2009)J/A+A/467/585 : Sources detected by ISGRI (Bodaghee+, 2007)J/ApJ/613/1179 : X-ray sources in Galactic Center (Muno+, 2004)J/PAZh/30/430 : INTEGRAL X-ray source in Galactic center (Revnivtsev+, 2004)J/A+A/411/L59 : INTEGRAL reference catalog (Ebisawa+, 2003)http://irfu.cea.fr/Sap/IGR-Sources/ : INTEGRAL sources (IGR list)http://cxc.cfa.harvard.edu/ : Chandra X-ray Observatory home pagehttp://hea.iki.rssi.ru/integral/nine-years-galactic-survey/ : INTEGRAL 9yrhttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/816/38https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/816/38http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/816/38https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/816/38https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/816/38http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/816/38GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/816/38/table5 (Chandra sources in IGR source fields)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/816/38/table5?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/816/38/table5?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/816/38/table5?GETtext/xml+votable180.050000true212.19175-61.13172220.0055555555555555566/14796 28783 28869 29210 29284 29526 29527 41681 41683 41684 41686 41818 42444https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/816/38?format=asciiX-rayGamma-raydefaultJ/ApJ/816/38/table5Chandra sources in IGR source fieldsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIGRIGR field name (JHHMMm+DDMM)obs.fieldcharSeq[1/29] Source numbermeta.id;meta.mainintSep[0.1/10] Angular distance between the center of the INTEGRAL error circle and the source (1)arcminstat.error;pos.angDistancefloatRAJ2000Chandra hour of right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Chandra degree of declination (J2000)pos.eq.dec;meta.mainPosErr[0.6/13] 90% confidence uncertainty on position (2)arcsecstat.error;stat.fit.paramfloatCts[2.1/405] Chandra/ACIS-I 0.3-10keV counts (3)ctphot.count;em.X-rayfloatE_Cts[2.9/21] Positive uncertainty on Ctsctstat.error;stat.maxfloate_Cts[1.7/20] Negative uncertainty on Ctsctstat.errorfloatl_HRLimit flag on HRmeta.code.errorcharHR[-0.7/1]? Hardness (4)phot.fluxfloatnullablee_HR[0.06/0.8]? HR uncertaintystat.errorfloatnullable