2006ApJ...647..256H


C.D.S. - SIMBAD4 rel 1.7 - 2021.08.05CEST01:39:13

2006ApJ...647..256H - Astrophys. J., 647, 256-264 (2006/August-2)

The formation epoch of early-type galaxies in the z ∼ 0.9 Cl 1604 supercluster.

HOMEIER N.L., MEI S., BLAKESLEE J.P., POSTMAN M., HOLDEN B., FORD H.C., BRADLEY L.D., DEMARCO R., FRANX M., ILLINGWORTH G.D., JEE M.J., MENANTEAU F., ROSATI P., VAN DER WEL A. and ZIRM A.

Abstract (from CDS):

We analyze the cluster color-magnitude relation (CMR) for early-type galaxies in two of the richer clusters in the z∼0.9 supercluster system to derive average ages and formation redshifts for the early-type galaxy population. Both clusters were observed with the Advanced Camera for Surveys on board the Hubble Space Telescope through the F606W and F814W filters, which brackets the rest-frame 4000 Å break at the cluster redshifts of z∼0.9. We fit the zero point and slope of the red cluster sequence and model the scatter about this relation to estimate average galaxy ages and formation redshifts. We find intrinsic scatters of 0.038-0.053 mag in (V606-I814) for the E and E+S0 populations, corresponding to average ages of 3.5-3.7 Gyr and formation redshifts zf=2.4-2.6. We find at least one significant difference between the Cl 1604+4304 and Cl 1604+4321 early-type CMRs. Cl 1604+4321, the less X-ray-luminous and massive of the two, lacks bright L* elliptical galaxies. We combine the galaxy samples to fit a composite CMR down to 0.15L* and find that the slope of the combined cluster CMR is significantly steeper than for RX J0152.7-1357 but consistent with MS 1054-03, both at similar redshift. The slope of the Cl 1604 CMR at the bright end (L>0.5L*) is flatter and consistent with the CMR slopes found for other high-redshift clusters. We find evidence for increasing scatter with increasing magnitude along the early-type CMR, consistent with a ``downsizing'' scenario, indicating younger mean ages with decreasing galaxy mass.

Abstract Copyright:

Journal keyword(s): galaxies: clusters: individual (Cl 1604) - Galaxies: Elliptical and Lenticular, cD - Galaxies: Evolution

CDS comments: Parag. 6 : Cl 0910+5442 is a misprint for ClG J0910+5422

Simbad objects: 11

goto Full paper

goto View the reference in ADS

Number of rows : 11

N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2021
#notes
1 ClG J0152-1358 ClG 01 52 41.3 -13 58 13           ~ 245 3
2 ClG J0848+4453 ClG 08 48 34.800 +44 53 41.90           ~ 122 1
3 ClG J0849+4452 ClG 08 48 56.3 +44 52 16           ~ 104 1
4 ClG J0910+5422 ClG 09 10 44.9 +54 22 09           ~ 87 0
5 ClG 1054-03 ClG 10 57 00.2 -03 37 27     22     ~ 451 0
6 ClG J1252-2927 ClG 12 52 54.4 -29 27 17           ~ 151 0
7 NAME Cl J1604 Supercluster SCG 16 04 +43.0           ~ 44 1
8 ClG 1603+4313 ClG 16 04 23.7 +43 04 52           ~ 130 1
9 ClG 1603+4329 SCG 16 04 31.5 +43 21 17           ~ 35 1
10 [PLO2001] J1604+4321 2670 GiC 16 04 33.69 +43 21 03.2           ~ 2 1
11 NAME Lynx Supercluster SCG ~ ~           ~ 24 1

    Equat.    Gal    SGal    Ecl

To bookmark this query, right click on this link: simbad:objects in 2006ApJ...647..256H and select 'bookmark this link' or equivalent in the popup menu


2021.08.05-01:39:13

© Université de Strasbourg/CNRS

    • Contact