J/MNRAS/464/183ivo://CDS.VizieR/J/MNRAS/464/183doi:10.26093/cds/vizier.74640183CDSNascimento R.S.Ribeiro A.L.B.Lopes P.A.A.2024-08-16T20:19:24Z2018-08-29T12:14:40ZCDS support team

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

cds-question@unistra.frgalaxy-clustersgalaxy-kinematicsredshiftedWe investigate segregation phenomena in galaxy groups in the range of 0.2<z<1. We study a sample of groups selected from the 4th Data Release of the DEEP2 galaxy redshift survey. We used only groups with at least eight members within a radius of 4 Mpc. Outliers were removed with the shifting gapper technique and, then, the virial properties were estimated for each group. The sample was divided into two stacked systems: low(z<=0.6) and high (z>0.6) redshift groups. Assuming that the colour index (U-B)_0_ can be used as a proxy for the galaxy type, we found that the fraction of blue (star-forming) objects is higher in the high-z sample, with blue objects being dominant at M_B_>-19.5 for both samples, and red objects being dominant at M_B_<-19.5 only for the low-z sample. Also, the radial variation of the red fraction indicates that there are more red objects with R<R_200_ in the low-z sample than in the high-z sample. Our analysis indicates statistical evidence of kinematic segregation, at the 99 per cent c.l., for the low-z sample: redder and brighter galaxies present lower velocity dispersions than bluer and fainter ones. We also find a weaker evidence for spatial segregation between red and blue objects, at the 70 per cent c.l. The analysis of the high-z sample reveals a different result: red and blue galaxies have velocity dispersion distributions not statistically distinct, although redder objects are more concentrated than the bluer ones at the 95 per cent c.l. From the comparison of blue/red and bright/faint fractions, and considering the approximate lookback time-scale between the two samples (~3Gyr), our results are consistent with a scenario where bright red galaxies had time to reach energy equipartition, while faint blue/red galaxies in the outskirts infall to the inner parts of the groups, thus reducing spatial segregation from z~0.8 to z~0.4.2017MNRAS.464..183Nhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/464/183CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/ApJ/751/50 : Galaxy groups catalog from DEEP2 Redshift Survey (Gerke+ 2012)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/464/183https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/464/183http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/464/183https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/464/183https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/464/183http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/464/183GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/464/183/table1 (Velocity dispersion, characteristic radii and masses of DEEP2 groups)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/464/183/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/464/183/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/464/183/table1?GETtext/xml+votable180.050000true215.0325161153.1012150.0055555555555555565/4697 6/9342-9343 9428-9429 11424-11426 11428 17766-17767 17772https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/464/183?format=asciidefaultJ/MNRAS/464/183/table1Velocity dispersion, characteristic radii and masses of DEEP2 groupsID[1/2321] Sequential numbermeta.recordintzRedshiftsrc.redshiftdoublerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000Right ascension (J2000)degpos.eq.ra;meta.mainDEJ2000Declination (J2000)degpos.eq.dec;meta.mainsigmaVelocity dispersionkm/sphys.veloc.dispersionfloate_sigmaError on sigma (lower value)km/sstat.errorfloatE_sigmaError on sigma (upper value)km/sstat.error;stat.maxfloato_sigmaNumber of galaxies used to compute the velocity dispersionmeta.numberintR500Radius within which the mean over-density of the cluster is 500 times the critical density at the cluster redshiftMpcphys.size.radiusdoublee_R500Error on R500 (lower value)Mpcstat.errordoubleE_R500Error on R500 (upper value)Mpcstat.error;stat.maxdoubleM500Mass for a radius of R5001e+14solMassphys.massdoublee_M500Error on M500 (lower value)1e+14solMassstat.errordoubleE_M500Error on M500 (upper value)1e+14solMassstat.error;stat.maxdoubleR200Radius within which the mean over-density of the cluster is 200 times the critical density at the cluster redshiftMpcphys.size.radiusdoublee_R200Error on R200 (lower value)Mpcstat.errordoubleE_R200Error on R200 (upper value)Mpcstat.error;stat.maxdoubleM200Mass for a radius of R2001e+14solMassphys.massdoublee_M200Error on M200 (lower value)1e+14solMassstat.errordoubleE_M200Error on M200 (upper value)1e+14solMassstat.error;stat.maxdoubleSimbadSimbad column added by the CDSmeta.ref.urlchar