Related papers: Cluster Evolution in the ROSAT North Ecliptic Pole…
We use new models of stellar population synthesis to estimate the fraction of stars formed during the last major bursts of star formation in E/S0 galaxies in low-redshift clusters ($z\simlt0.4$) from the spectral signatures of…
We present a quantitative study of the X-ray morphology of galaxy clusters, as a function of their detection method and redshift. We analyze two separate samples of galaxy clusters: a sample of 36 clusters at 0.35 < z < 0.9 selected in the…
The current formation models for cluster elliptical galaxies which incorporate a mechanism for the metallicity enhancement of massive ellipticals predict a change in the observed slope of the red sequence of ellipticals as a function of…
General relativistic effects have long been predicted to subtly influence the observed large-scale structure of the universe. The current generation of galaxy redshift surveys have reached a size where detection of such effects is becoming…
The evolution of the cluster mass function and the cluster correlation function from z = 0 to z = 3 are determined using 10^6 clusters obtained from high-resolution simulations of the current best-fit LCDM cosmology (\Omega_m = 0.27,…
We have studied the evolution of galaxian morphologies from ground-based, good-seeing images of 9 clusters at z=0.09-0.25. The comparison of our data with those relative to higher redshift clusters (Dressler et al. 1997) allowed us to trace…
We analyze with hydrodynamical simulations the evolution of galaxy clusters in a cosmological environment. Power ratios (Buote \& Tsai 1995) are used to quantitatively relate cluster morphologies to their dynamical states. The simulated…
We present results of an investigation of clustering evolution of field galaxies between a redshift of z\~1 and the present epoch. The current analysis relies on a sample of ~14000 galaxies in two fields of the COMBO-17 survey. The redshift…
Using three newly identified galaxy clusters at z~1 (photometric redshift) we measure the evolution of the galaxies within clusters from high redshift to the present day by studying the growth of the red cluster sequence. The clusters are…
The redshift evolution of the galaxy two-point correlation function is a fundamental cosmological statistic. To identify similar galaxy populations at different redshifts, we select a strict volume-limited sample culled from the 6100…
Obtaining large samples of galaxy clusters is important for cosmology, since cluster counts as a function of redshift and mass can constrain the parameters of our Universe. They are also useful to understand the formation and evolution of…
Two-dimensional surface photometry has been done for 166 {\em early-type} galaxies (bulge/total luminosity $B/T>0.6$) in 3 fields of the Canadian Network for Observational Cosmology (CNOC) cluster survey. These galaxies are either…
Ongoing and planned wide-area surveys at optical and infrared wavelengths should detect a few times 10^5 galaxy clusters, roughly 10% of which are expected to be at redshifts >~ 0.8. We investigate what can be learned about the X-ray…
We present a selection of ROSAT results on the morphology, the evolution, and the masses of galaxy clusters and groups. ROSAT provides the first complete X-ray view on the Virgo cluster: it reveals a complex structure similar to the optical…
This paper given at the meeting on "Mapping, Measuring and Modelling the Universe" presents three topics: 1) the study of the clusters and groups of galaxies found serendipitously in the North Ecliptic Pole (NEP) region of the ROSAT all-sky…
We measure the evolution of clustering for galaxies with different spectral types from 6495 galaxies with 17.5<=I_AB<=24 and measured spectroscopic redshift in the first epoch VIMOS-VLT Deep Survey. We classify our sample into 4 classes,…
We present the ellipticity distribution and its evolution for early-type galaxies in clusters from z~0.8 to z~0, based on the WIde-field Nearby Galaxy-cluster Survey (WINGS)(0.04<z<0.07), and the ESO Distant Cluster Survey…
We measure the spatial clustering of galaxies as a function of their morphological type at z~0.8, for the first time in a deep redshift survey with full morphological information. This is obtained by combining high-resolution HST imaging…
We describe Hubble Space Telescope (HST) imaging of 10 of the 20 ESO Distant Cluster Survey (EDisCS) fields. Each ~40 square arcminute field was imaged in the F814W filter with the Advanced Camera for Surveys Wide Field Camera. Based on…
We study the morphological content of a large sample of high-redshift clusters to determine its dependence on cluster mass and redshift. Quantitative morphologies are based on bulge+disk decompositions of cluster and field galaxies on deep…