J/MNRAS/450/2261ivo://CDS.VizieR/J/MNRAS/450/2261doi:10.26093/cds/vizier.74502261CDSMorandi A.Sun M.Forman W.Jones C.2024-08-14T20:21:45Z2016-01-29T16:38:14ZCDS support team

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

cds-question@unistra.frgalaxy-clustersx-ray-sourcesWe studied the physical properties of the intracluster medium (ICM) in the virialization region of a sample of 320 clusters (0.056<z<1.24, kT>~3keV) in the Chandra archive. With the emission measure profiles from this large sample, the typical gas density, gas slope and gas fraction can be constrained out to and beyond R200. We observe a steepening of the density profiles beyond R500 with {beta}~0.68 at R500 and {beta}~1 at R200 and beyond. By tracking the direction of the cosmic filaments approximately with the ICM eccentricity, we report that galaxy clusters deviate from spherical symmetry, with only small differences between relaxed and disturbed systems. We also did not find evolution of the gas density with redshift, confirming its self-similar evolution. The value of the baryon fraction reaches the cosmic value at R200; however, systematics due to non-thermal pressure support and clumpiness might enhance the measured gas fraction, leading to an actual deficit of the baryon budget with respect to the primordial value. This study has important implications for understanding the ICM physics in the outskirts.2015MNRAS.450.2261Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/450/2261CatalogResearchIsServedByTAP VizieR generic servicerelated-toB/chandra : The Chandra Archive Log (CXC, 1999-2014)IX/45 : The Chandra Source Catalog, Release 1.1 (Evans+ 2012)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/450/2261https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/450/2261http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/450/2261https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/450/2261https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/450/2261http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/450/2261GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapX-raydefaultJ/MNRAS/450/2261/table1The X-ray properties of the galaxy clusters in our sampleSimbadNameSimbad column added by the CDSmeta.idcharzRedshiftsrc.redshiftfloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintClusterCluster namemeta.id;meta.mainchartexpExposure timekstime.duration;obs.exposurefloatTewSpectroscopic temperature in the radial range 0.15-0.75R500keVphys.temperaturefloate_Tewrms uncertainty on TewkeVstat.errorfloatwCentroid shift (in units of R500)pos.distance;arith.difffloate_wrms uncertainty on wstat.errorfloatFlag[CC NCC] flag for the presence (CC) or not (NCC) of a cooling coremeta.code.errorcharIDIdentification number of the Chandra observations, separated by commameta.numberchar