Related papers: Cluster Populations in Abell 2125 and 2218
Using our extensive radio, optical, near-IR and X-ray imaging and spectroscopy, we consider the reason for the unusually large number of radio detected galaxies, mostly found outside the cluster core, in Abell 2125 (z=0.2465, richness class…
We discuss the galaxy population of the rich cluster MS1621.5+2640 at z=0.4274, based on spectra and imaging in a field of size 9 arcmin by 23 arcmin (~2 by 5 h**-1 Mpc). The sample comprises 277 galaxies, of which 112 are cluster members,…
Radio continuum emission at 1.4 GHz was used to identify active galaxies in a sample of 20 nearby Abell clusters. The radio emission indicates either an active galactic nucleus or current star formation, and optical spectroscopy was used to…
We present a spectrophotometric analysis of the galaxy pop. in the area of the merging cluster Abell 3921 at redshift 0.093. We investigate the impact of the complex cluster environment on galaxy properties such as morphology or star…
(Abriged) This is a short review on the evolution of elliptical and lenticular/S0 galaxies in the dense environment of rich clusters for look-back times of more than half the age of the Universe. In addition, new data are presented for the…
The structure of the universe is believed to have formed by clustering hierarchically from small to large scales. Much of this evolution occurs very slowly but at a few special times more, rapid, violent activity may occur as major subunits…
We compare V-band structural properties of cluster and field galaxies, to test whether much of the current cluster membership resulted from the transformation of infalling spirals into red early types. We use 140 galaxies from 3 z<0.6 Abell…
Using data of five clusters of galaxies within the redshift range 0.15 $\leq$ z $\leq$ 0.25, imaged with the Nordic Optical Telescope (NOT) in the central $\approx$ 1 Mpc$^2$ in very good seeing conditions, we have performed an exhaustive…
Using photometric redshifts we determine the galaxy population of the clusters of galaxies Cl0016+16 at z=0.55, Cl1600+41 at z=0.54, Cl1601+42 at z=0.54 and MS1008-1224 at z=0.31. Comparing the clusters, we find no evidence for a universal…
We present a principal component analysis of galaxy spectra from the CNOC sample of rich X-ray luminous clusters at 0.18 < z < 0.55. Composite radial distributions of different stellar populations show strong gradients as a function of…
~Deep photometric data in the V-, R-, I-, z- and K-bands for the cluster of galaxies EIS 0048-2942 are used to investigate the properties of the galaxy populations at z~0.64 in a field of 2.5x2.5 Mpc^2. The sample of candidate cluster…
Although field galaxy studies have begun to probe the universe at z > 1, evidence for galaxy clusters at such redshifts has been sparse. New observations are accumulating rapidly, however, providing new data on the early evolution of…
We present a study of the luminosity and color properties of galaxies selected from a sample of 57 low-redshift Abell clusters. We utilize the non-parametric dwarf-to-giant ratio (DGR) and the blue galaxy fraction (fb) to investigate the…
Rest frame Stromgren photometry (3500A, 4100A, 4750A and 5500A) is presented for 509 galaxies in 17 rich clusters between z=0 and z=1 as a test of color evolution. Our observations confirm a strong, rest frame, Butcher-Oemler effect where…
We present a model for the broad morphological distinction between the disk and spheroidal components of galaxies. Elaborating on the hierarchical clustering scheme of galaxy formation proposed by Cole et al., we assume that galaxies form…
We present the results of Butcher-Oemler-style analysis of three moderate- redshift (0.1<z<0.2) clusters which have bimodal X-ray surface brightness profiles. We find that at least two of these clusters exhibit unusually high fractions of…
By means of our own cosmological-hydrodynamical simulation and semi-analytical model we studied galaxy population properties in clusters and groups, spanning over 10 different bands from UV to NIR, and their evolution since redshift z=2. We…
Based on a deep ROSAT/PSPC observation, we reveal an elongated complex of extended X-ray-emitting objects in and around the galaxy cluster A2125. Multicolor optical imaging of galaxies in the field suggests that this complex represents a…
We present deep optical and near-infrared imaging of the rich cluster A2218 at z=0.17. Our optical imaging comes from new multicolour Hubble Space Telescope WFPC2 observations in the F450W (B), F606W (V) and F814W (I) passbands. These…
The existence of a clumpy, large-scale filamentary structure is at the basis of the current paradigm of cosmic formation and evolution of clusters. The star-formation history of galaxies falling into a cluster is altered as a result of the…