相关论文: Line-of-Sight Anisotropies within X-ray Luminous C…
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 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 an analysis of the X-ray emission for a complete sample of 288 Abell clusters spanning the redshift range 0.016<= z <= 0.09 from the ROSAT All-Sky Survey. This sample is based on our 20cm VLA survey of nearby Abell clusters. We…
We study the redshift space correlation function of galaxy clusters for observational samples constructed in different surveys. We explore correlation amplitudes, pairwise velocity distributions and bias factors. Systematics in cluster…
We analyse three clusters of galaxies, Abell 901 (z=0.17), Abell 1437 (z=0.13) and Abell 3570 (z=0.037). They have low to intermediate X-ray fluxes and an irregular morphology in the ROSAT All-Sky Survey (RASS). These clusters are chosen to…
We introduce a new test to study the Cosmological Principle with galaxy clusters. Galaxy clusters exhibit a tight correlation between the luminosity and temperature of the X-ray-emitting intracluster medium. While the luminosity measurement…
Investigations of the cluster environment of radio sources have not shown a correlation between radio power and degree of clustering. However, it has been demonstrated that extended X-ray luminosity and galaxy clustering do exhibit a…
We present an analysis of the colour-magnitude relation for a sample of 56 X-ray underluminous Abell clusters, aiming to unveil properties that may elucidate the evolutionary stages of the galaxy populations that compose such systems. To do…
We present a search for gravitational arcs in a sample of X-ray luminous, medium redshift clusters of galaxies. The sample of clusters is called ARCRAIDER, is based on the ROSAT Bright Survey (RBS) and fulfills the following criteria: (a)…
We present the results of our analyses of the X-ray emission and of the strong lensing systems in the relaxed galaxy cluster Abell 611 (z=0.288). We infer the X-ray mass estimate deriving the density and temperature profiles of the…
We compute the cluster auto-correlation function $\xi_{cc}(r)$ of an X-ray flux limited sample of Abell clusters (XBACs, \cite{ebe}). For the total XBACs sample we find a power-law fit $\xi_{cc}=(r/r_0)^{\gamma}$ with $r_0=21.1$ Mpc…
Large-scale fluctuations of the X-ray background are investigated using the ROSAT All-Sky Survey. The autocorrelation function of the extragalactic background at 1 keV is determined at separations 0.1 - 40 deg. We detect a significant…
We present an analysis of the 2-point correlation function, of the X-ray Brightest Abell-type Cluster sample (XBACs; Ebeling et al. 1998) and of the cosmological constraints that it provides. If \xi(r) is modelled as a power-law, we find…
We present here the Spatial Two--Point Correlation Function for a complete sample of 67 X--ray selected Abell clusters of galaxies. We find a correlation length of $16.1\pm3.4\mpc$ with no significant clustering beyond $\simeq40\mpc$. This…
Results are presented from the analysis of ROSAT HRI and PSPC observations of the CNOC subsample of the EMSS high redshift galaxy clusters. X-ray surface brightness profiles of 14 clusters with $0.17 < z < 0.55$ are constructed and fit to…
For a detailed comparison of the appearance of cluster of galaxies in X-rays and in the optical, we have compiled a comprehensive database of X-ray and optical properties of a sample of clusters based on the largest available X-ray and…
In this paper we consider a large sample of optically selected clusters, in order to elucidate the physical reasons for the existence of X-ray underluminous clusters. For this purpose we analyze the correlations of the X-ray and optical…
We have measured the surface density of galaxies toward 14 X-ray-selected cluster candidates at redshifts greater than z=0.46, and we show that they are associated with rich galaxy concentrations. We find that the clusters range between…
The isotropy of the late Universe is an assumption greatly used in astronomy. However, many studies have recently reported deviations from isotropy with a definitive conclusion yet to be made. New, independent methods to robustly test the…
For a detailed comparison of the appearance of cluster of galaxies in X-rays and in the optical, we have compiled a comprehensive database of X-ray and optical properties of a sample of clusters based on the largest available X-ray and…