The Evolutionary Status of Clusters of Galaxies at z ~ 1

Abstract

Combined HST, X-ray, and ground-based optical studies show that clusters of galaxies are largely "in place" by $z\sim 1$, an epoch when the Universe was less than half its present age. High resolution images show that elliptical, S0, and spiral galaxies are present in clusters at redshifts up to $z\sim 1.3$. Analysis of the CMDs suggest that the cluster ellipticals formed their stars several Gyr earlier, near redshift 3. The morphology--density relation is well established at $z\sim 1$, with star-forming spirals and irregulars residing mostly in the outer parts of the clusters and E/S0s concentrated in dense clumps. The intracluster medium has already reached the metallicity of present-day clusters. The distributions of the hot gas and early-type galaxies are similar in $z\sim 1$ clusters, indicating both have largely virialized in the deepest potentials wells. In spite of the many similarities between $z\sim 1$ and present-day clusters, there are significant differences. The morphologies revealed by the hot gas, and particularly the early-type galaxies, are elongated rather than spherical. We appear to be observing the clusters at an epoch when the sub-clusters and groups are still assembling into a single regular cluster. Support for this picture comes from CL0152 where the gas appears to be lagging behind the luminous and dark mass in two merging sub-components. Moreover, the luminosity difference between the first and second brightest cluster galaxies at $z\sim 1$ is smaller than in 93% of present-day Abell clusters, which suggests that considerable luminosity evolution through merging has occurred since that epoch. Evolution is also seen in the bolometric X-ray luminosity function.

18 pages, 12 figures, to appear in Penetrating Bars through Masks of Cosmic Dust: the Hubble Tuing Fork Strikes a New Note, eds. D.L. Block, K.C. Freeman, I. Puerari & R. Groess. Figures degraded to meet astroph size limit; a version with higher resolution figures may be downloaded from: http://acs.pha.jhu.edu/~jpb/z1clusters/ford_clusters.pdf

References in corpus (8)

• Advanced Camera for Surveys Photometry of the Cluster RDCS1252.9-2927: The Color-Magnitude Relation at z=1.24
• Scaling laws in X-ray Galaxy Clusters at redshift between 0.4 and 1.3
• The Fundamental Plane at z=1.27: First Calibration of the Mass Scale of Red Galaxies at Redshifts z>1
• Chandra and XMM-Newton Observations of RDCS1252.9-2927, A Massive Cluster at z=1.24
• Iron abundance in the ICM at high redshift
• Evolution in the Color-Magnitude Relation of Early-Type Galaxies in Clusters of Galaxies at z~=1
• Chandra X-ray analysis of the massive high-redshift galaxy clusters ClJ1113.1-2615 and ClJ0152.7-1357
• Deep near-infrared imaging of RDCS J1252.9-2927 at z=1.237: The colour-magnitude diagram

Cited by in corpus (7)

• Star Formation Histories in a Cluster Environment at z~0.84
• Early-type galaxies at z~1.3. II. Masses and ages of early-type galaxies in different environments and their dependence on stellar population model assumptions
• Crowded Field Galaxy Photometry: Precision Colors in the CLASH Clusters
• Evidence for the Universality of Properties of Red-Sequence Galaxies in X-ray- and Red-Sequence-Selected Clusters at z ~ 1
• Galaxy Clusters in the IRAC Dark Field I: Growth of the red sequence
• Superdisks in Radio Galaxies: Jet-Wind Interactions
• The Morphological Transformation of Red-Sequence Galaxies in the Distant Cluster XMMU J1229+0151