Related papers: Optical and X-ray clusters as tracers of the super…
A study of the globular cluster systems of 23 brightest, or central, galaxies in 19 Abell clusters has recently been completed. This Letter presents some of the newly discovered correlations of the globular cluster specific frequency $S_N$…
We present a comparison of X-ray and optical luminosities and luminosity functions of cluster candidates from a joint optical/X-ray survey, the ROSAT Optical X-Ray Survey. Completely independent X-ray and optical catalogs of 23 ROSAT fields…
The cluster correlation function and its richness dependence are determined from 1108 clusters of galaxies -- the largest sample of clusters studied so far -- found in 379 deg^2 of Sloan Digital Sky Survey early data. The results are…
We present a statistical analysis of the largest X-ray survey of nearby spiral galaxies in which diffuse emission has been separated from discrete source contributions. Regression and rank-order correlation analyses are used to compare…
The X-ray galaxy cluster sample from the REFLEX Cluster Survey, which covers the X-ray brightest galaxy clusters detected in the ROSAT All-Sky Survey in the southern sky, is used to construct the X-ray luminosity function of clusters in the…
We analyse the spatial clustering properties of the RASS1 Bright Sample, an X-ray flux-limited catalogue of galaxy clusters selected from the southern part of the $ROSAT$ All-Sky Survey. The two-point correlation function $\xi(r)$ of the…
We use the two-point correlation function in redshift space, $\xi(s)$, to study the clustering of the galaxies and groups of the Nearby Optical Galaxy (NOG) Sample, which is a nearly all-sky, complete, magnitude-limited sample of \~7000…
The present state of X-ray observations of cool stars in coeval open clusters is reviewed. Concentrating on ROSAT results for solar-type stars, the available observational dataset is summarized along with those details of the evolution of…
An analysis of R >= 1 Abell clusters is presented for samples containing recent redshifts from the MX Northern Abell Cluster Survey. The newly obtained redshifts from the MX Survey as well as those from the ESO Nearby Abell Cluster Survey…
We present measurements of the angular correlation function of galaxies selected from a B_J=23.5 multicolour survey of two 5 degree by 5 degree fields located at high galactic latitudes. The galaxy catalogue of approximately 400,000…
We aim to quantify the capability of the inhomogeneous distribution of galaxy clusters, represented by the two-point statistics in Fourier space, to retrieve information on the underlying scaling relations. We make a case study using the…
It is shown that galaxy cluster surveys selecting clusters by their X-ray luminosity effectively select by cluster mass. It is shown that a selection based solely on Abell galaxy richness is less efficient in terms of mass. Furthermore the…
The intensity of the soft X-Ray background is correlated with the distribution of galaxies. To demonstrate this, magnitude limited galaxy samples extracted from bright galaxy catalogues and the Lick counts are utilized. Significant…
Two-dimensional high-resolution density field of galaxies of the Early Data Release of the Sloan Digital Sky Survey with a smoothing lengths 0.8 h^{-1} Mpc is applied to extract clusters of galaxies, and a low-resolution field with…
We present an essentially complete, all-sky, X-ray flux limited sample of 242 Abell clusters of galaxies (six of which are double) compiled from ROSAT All-Sky Survey data. Our sample is uncontaminated in the sense that systems featuring…
We present a detailed comparison of mass measurements for clusters of galaxies using ASCA and ROSAT X-ray data and constraints from strong and weak gravitational lensing. Our results for a sample of 13 clusters provide a consistent…
We apply fractal analysis methods to investigate the scaling properties in the Abell and ACO catalogs of rich galaxy clusters. We also discuss different technical aspects of the method when applied to data sets with small number of points…
We investigate the dependence of several galaxy properties on the environment and cluster identification techniques. We select clusters of galaxies from two catalogues based on the SDSS: the ROSAT-SDSS Galaxy Cluster Survey, and the MaxBCG…
We use the weak gravitational lensing effect to study the mass distribution and dynamical state of a sample of 24 X-ray luminous clusters of galaxies ($0.05<z<0.31$) observed with the VLT-FORS1 under homogeneous sky conditions and…
Galaxies are not uniformly distributed in space. On large scales the Universe displays coherent structure, with galaxies residing in groups and clusters on scales of ~1-3 Mpc/h, which lie at the intersections of long filaments of galaxies…