J/ApJ/552/427ivo://CDS.VizieR/J/ApJ/552/427doi:10.26093/cds/vizier.15520427CDSCarlberg R.G.Yee H.K.C.Morris S.L.Lin H.Hall P.B.Patton D.R.,Sawicki M.Shepherd C.W.2017-12-05T05:10:52Z2010-09-24T12:17:25ZCDS support team

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

cds-question@unistra.frredshiftedgalaxy-kinematicssurveysGalaxy groups likely to be virialized are identified within the CNOC2, (Yee et al., 2000, Cat. <J/ApJS/129/475>) intermediate-redshift galaxy survey. The resulting groups have a median velocity dispersion, {sigma}1=~200km/s. The virial mass-to-light ratios, using k-corrected and evolution-compensated luminosities, have medians in the range of 150-250h M_{suns}_/L_{sun}_, depending on group definition details. The number-velocity dispersion relation at {sigma}1>~200km/s is in agreement with the low-mass extrapolation of the cluster-normalized Press-Schechter model. Lower velocity dispersion groups are deficient relative to the Press-Schechter model. The two-point group-group autocorrelation function has r0=6.8+/-0.3h^-1^Mpc, which is much larger than the correlations of individual galaxies, but about as expected from biased clustering. The mean number density of galaxies around group centers falls nearly as a power law with r^-2.5^ and has no well-defined core. The projected velocity dispersion of galaxies around group centers is either flat or slowly rising outward. The combination of a steeper than isothermal density profile and the outward rising velocity dispersion implies that the mass-to-light ratio of groups rises with radius if the velocity ellipsoid is isotropic but could be nearly constant if the galaxy orbits are nearly circular. Such strong tangential anisotropy is not supported by other evidence. Although the implication of a rising M/L must be viewed with caution, it could naturally arise through dynamical friction acting on the galaxies in a background of "classical" collisionless dark matter.2001ApJ...552..427Chttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/552/427CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVII/256 : Groups of Galaxies from CfA2 Redshift Survey (Mahtessian++, 2010)VII/213 : Hickson's Compact groups of Galaxies (Hickson+ 1982-1994)J/A+A/474/783 : Main galaxy groups from SDSS-DR5 (Deng+, 2007)J/ApJ/625/6 : Galaxy groups in the DEEP2 Galaxy Redshift Survey (Gerke+,J/AJ/123/2976 : The UZC-SSRS2 group catalog (Ramella+, 2002)J/A+A/381/420 : Group of Galaxies in the SSRS2 catalog (Adami+, 2002)J/ApJS/129/475 : The CNOC2 survey. I. (Yee+, 2000)J/A+A/342/1 : ESO Slice Project. VI. Groups of Galaxies. (Ramella+ 1999)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/552/427https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/552/427http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/552/427https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/552/427https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/552/427http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/552/427GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/552/427/table1 (The r_z_^max^=5h^-1^Mpc, r_p_^max^=0.25h^-1^Mpc groups)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/552/427/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/552/427/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/552/427/table1?GETtext/xml+votable180.050000true36.4842620.944220.0055555555555555565/1440 6/8339 8342 17769 17772 17774 18957 18962 18968 18969https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/552/427?format=asciiOpticaldefaultJ/ApJ/552/427/table1The r_z_^max^=5h^-1^Mpc, r_p_^max^=0.25h^-1^Mpc groupsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameCommon group name (HHMM+DD) (1)meta.id.parentcharRAB1950Right Ascension (B1950)pos.eq.ra;meta.mainDEB1950Declination (B1950)pos.eq.dec;meta.mainzSpectroscopic redshiftsrc.redshiftdoublesigmaMedian velocity dispersionkm/sphys.veloc.dispersion;stat.medianinte_sigmaUncertainty in sigmakm/sstat.errorintM/LThe virial mass-to-light ratio (2)solMass/solLumphys.luminosityinte_M/LUncertainty in M/L (2)solMass/solLumstat.errorintNzNumber of group members with redshiftsmeta.numberintMassGroup mass (2)solMassphys.massdoublee_MassPercent uncertainty in Mass (2)%stat.error;phys.massintSimbadSimbad column added by the CDSmeta.refcharNEDSimbad column added by the CDSmeta.refchar_RA.icrsRight ascension (ICRS) (computed by VizieR, not part of the original data)pos.eq.ranullableindexed_DE.icrsDeclination (ICRS) (computed by VizieR, not part of the original data)pos.eq.decnullableindexed