J/ApJ/716/1514ivo://CDS.VizieR/J/ApJ/716/1514doi:10.26093/cds/vizier.17161514CDSYao Y.Wang Q.D.Penton S.V.Tripp T.M.Shull J.M.Stocke J.T.2017-12-18T07:57:18Z2012-06-21T12:17:30ZCDS support team

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

cds-question@unistra.fractive-galactic-nucleigalaxiesredshiftedx-ray-sourcesThe circumgalactic medium (CGM) around galaxies is believed to record various forms of galaxy feedback and contain a significant portion of the "missing baryons" of individual dark matter halos. However, clear observational evidence for the existence of the hot CGM is still absent. We use intervening galaxies along 12 background active galactic nuclei (AGNs) as tracers to search for X-ray absorption lines produced in the corresponding CGM. Stacking Chandra grating observations with respect to galaxy groups and different luminosities of these intervening galaxies, we obtain spectra with signal-to-noise ratios of 46-72 per 20m{AA} spectral bin at the expected OVIIK{alpha} line. We find no detectable absorption lines of CVI, NVII, OVII, OVIII, or NeIX. The high spectral quality allows us to tightly constrain upper limits to the corresponding ionic column densities (in particular log[N_OVII_(cm^-2^)]<=14.2-14.8). These nondetections are inconsistent with the Local Group hypothesis of the X-ray absorption lines at z~0 commonly observed in the spectra of AGNs. These results indicate that the putative CGM in the temperature range of 10^5.5^-10^6.3^K may not be able to account for the missing baryons unless the metallicity is less than 10% solar.2010ApJ...716.1514Yhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/716/1514CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toB/chandra : The Chandra Archive Log (CXC, 1999-2012)IX/19 : X-ray lightcurves of bright AGNs from Ginga (Hayashida+ 1998)J/A+A/539/A149 : Multiwavelength view of blazar PKS 2155-304 (Abramowski+,J/MNRAS/392/1181 : BV(RI)c photometry of 3C 273 (Dai+, 2009)J/ApJS/182/378 : HI and OVI absorbers in nearby Universe (Wakker+, 2009)J/ApJ/701/1219 : Galaxy survey in 3 QSO fields (Chen+, 2009)J/ApJS/155/351 : Absorption toward PG 1116+215 (Sembach+, 2004)J/ApJ/508/200 : QSO low-z Ly{alpha} absorbers (Tripp+, 1998)J/PAZh/23/409 : Spectrophotometry of Mrk 509 (Chuvaev+, 1997)J/PASP/106/646 : HST quasar absorption-line key project. VIII. (Kirhakos+,https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/716/1514https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/716/1514http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/716/1514https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/716/1514https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/716/1514http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/716/1514GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/716/1514/table1 (Background AGNs, Chandra observations, and intervening galaxies)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/716/1514/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/716/1514/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/716/1514/table1?GETtext/xml+votable180.050000true275.488485664.34339610.005555555555555556Cone search capability for table J/ApJ/716/1514/table2 (Intervening galaxies along the 12 sight lines)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/716/1514/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/716/1514/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/716/1514/table2?GETtext/xml+votable180.050000true275.36564.2030.0055555555555555565/6573 6965 6/10599 10605 15351 15357 16671 16693 23134 26270 26271 26289 26336 26338 27771 27774 27856 27857 27859 27869 28270 28355 28356 28491 28495 28513 28515 28516 28517 28519 28528 28530 34881 43855 43866 43876 43877 47014 49042https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/716/1514?format=asciiX-rayOpticaldefaultJ/ApJ/716/1514/table1Background AGNs, Chandra observations, and intervening galaxiesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameSource name for sight linemeta.id;meta.maincharprimaryzAGNAGN redshiftsrc.redshiftfloatNoNumber of Chandra grating observationsmeta.numberintExpTotal exposure timekstime.duration;obs.exposureintNgNumber of intervening galaxies along the sight linemeta.numberintNbNumber of intervening galaxies with reported B magnitudes. (1)meta.numberintSimbadSimbad column added by the CDSmeta.refcharNEDSimbad column added by the CDSmeta.refchar_RAPositions from SIMBAD database (right ascension part)degpos.eq.ra;meta.main_DEPositions from SIMBAD database (declination part)degpos.eq.dec;meta.mainJ/ApJ/716/1514/table2Intervening galaxies along the 12 sight linesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameSource name for sight linemeta.id.assoccharRAJ2000Right Ascension in decimal degrees (J2000)degpos.eq.ra;meta.mainDEJ2000Declination in decimal degrees (J2000)degpos.eq.dec;meta.mainzGalSpectroscopic redshift z^i^_gal_src.redshiftdoubleDthetaAngular distancearcsecpos.angDistancefloatbImpact distance (r^i^_{rho}_; see eq. (1))kpcsrc.impactParamfloatBmag? The B band magnitudemagphot.mag;em.opt.BfloatnullableL/L*? The B band luminosity relative to L*phys.luminosity;arith.ratiofloatnullableT98Cross-match with Tripp et al., 1998, Cat. J/ApJ/508/200meta.ref.urlintnullableSimbadSimbad column added by the CDSmeta.refcharNEDSimbad column added by the CDSmeta.refchar