J/ApJ/697/1842ivo://CDS.VizieR/J/ApJ/697/1842doi:10.26093/cds/vizier.16971842CDSKnobel C.Lilly S.J.Iovino A.Porciani C.Kovac K.Cucciati O.,Finoguenov A.Kitzbichler M.G.Carollo C.M.Contini T.Kneib J.-P.,Le Fevre O.Mainieri V.Renzini A.Scodeggio M.Zamorani G.,Bardelli S.Bolzonella M.Bongiorno A.Caputi K.Coppa G.,de la Torre S.de Ravel L.Franzetti P.Garilli B.Kampczyk P.,Lamareille F.Le Borgne J.-F.Le Brun V.Maier C.Mignoli M.Pello R.,Peng Y.Montero E.P.Ricciardelli E.Silverman J.D.Tanaka M.,Tasca L.Tresse L.Vergani D.Zucca E.Abbas U.Bottini D.Cappi A.,Cassata P.Cimatti A.Fumana M.Guzzo L.Koekemoer A.M.Leauthaud A.,Maccagni D.Marinoni C.McCracken H.J.Memeo P.Meneux B.Oesch P.,Pozzetti L.Scaramella R.2017-11-29T11:49:02Z2011-06-22T09:12:41ZCDS support team

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

cds-question@unistra.frgalaxiescatalogsredshiftedWe present a galaxy group catalog spanning the redshift range 0.1<~z<~1 in the ~1.7deg^2^ COSMOS field, based on the first ~10000 zCOSMOS spectra. The performance of both the Friends-of-Friends (FOF) and Voronoi-Delaunay method (VDM) approaches to group identification has been extensively explored and compared using realistic mock catalogs. We find that the performance improves substantially if groups are found by progressively optimizing the group-finding parameters for successively smaller groups, and that the highest fidelity catalog, in terms of completeness and purity, is obtained by combining the independently created FOF and VDM catalogs. The final completeness and purity of this catalog, both in terms of the groups and of individual members, compares favorably with recent results in the literature. The current group catalog contains 102 groups with N>=5 spectroscopically confirmed members, with a further ~700 groups with 2<=N<=4. Most of the groups can be assigned a velocity dispersion and a dark-matter mass derived from the mock catalogs, with quantifiable uncertainties. The fraction of zCOSMOS galaxies in groups is about 25% at low redshift and decreases toward ~15% at z~0.8. The zCOSMOS group catalog is broadly consistent with that expected from the semianalytic evolution model underlying the mock catalogs.2009ApJ...697.1842Khttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/697/1842CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVII/256 : Groups of Galaxies from CfA2 Redshift Survey (Mahtessian++, 2010)VII/86 : Groups of Galaxies. I. Nearby Groups (Huchra+ 1982)J/A+A/520/A42 : Galaxy groups in the VIMOS-VLT Deep Survey (Cucciati+, 2010)J/ApJS/184/218 : The zCOSMOS 10k-bright spectroscopic sample (Lilly+, 2009)J/ApJS/172/70 : zCOSMOS-bright catalog (Lilly+, 2007)J/ApJ/625/6 : Galaxy groups in the DEEP2 Galaxy Redshift Survey (Gerke+,https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/697/1842https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/697/1842http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/697/1842https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/697/1842https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/697/1842http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/697/1842GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/697/1842/table3 (Group catalog)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/697/1842/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/697/1842/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/697/1842/table3?GETtext/xml+votable180.050000true150.00872.02870.005555555555555556Cone search capability for table J/ApJ/697/1842/table4 (Group galaxies)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/697/1842/table4?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/697/1842/table4?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/697/1842/table4?GETtext/xml+votable180.050000true150.06052.00670.0055555555555555565/6814 6/27245 27247https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/697/1842?format=asciiOpticaldefaultJ/ApJ/697/1842/table3Group catalogGrpIDRunning identification numbermeta.id;meta.mainintNGroup richnessmeta.numberintrecnoRecord 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.mainzGroup redshiftsrc.redshiftfloatsigmaFinal velocity dispersion estimate {sigma}km/sphys.veloc.dispersionintMfudgeThe "fudge" mass (1)solMassphys.massdoubleGRP1[0,1] First Group purity parameter (2)stat.paramfloatJ/ApJ/697/1842/table4Group galaxiesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintzCOSMOSGalaxy identificationmeta.id;meta.mainintGrpIDGroup identification; see Table 3meta.idintNGroup richnessmeta.numberintRAJ2000Right Ascension in decimal degrees (J2000)degpos.eq.ra;meta.mainDEJ2000Declination in decimal degrees (J2000)degpos.eq.dec;meta.mainzzCOSMOS 10k-bright spectroscopic redshift (Lilly et al. 2009, Cat. J/ApJS/184/218)src.redshiftfloatGAP[0,2] Galaxy purity parameter (1)stat.paramintSimbadSimbad column added by the CDScharNEDSimbad column added by the CDSchar