ﻻ يوجد ملخص باللغة العربية
We present the statistically complete and cosmologically most relevant subset of the twelve most distant galaxy clusters detected at z>0.5 by the MAssive Cluster Survey (MACS). Ten of these systems are new discoveries; only two (MACSJ0018.5+1626 aka CL0016+1609, and MACSJ0454.1-0300 aka MS0451.6-0305) were previously known. We provide fundamental cluster properties derived from our optical and X-ray follow-up observations as well as the selection function in tabulated form to facilitate cosmological studies using this sample.
We present the results of work involving a statistically complete sample of 34 galaxy clusters, in the redshift range 0.15$le$z$le$0.3 observed with $Chandra$. We investigate the luminosity-mass ($LM$) relation for the cluster sample, with the masses
We report the discovery of a compact supercluster structure at z=0.9. The structure comprises three optically-selected clusters, all of which are detected in X-rays and spectroscopically confirmed to lie at the same redshift. The Chandra X-ray temper
We report on the discovery of a very distant galaxy cluster serendipitously detected in the archive of the XMM-Newton mission, within the scope of the XMM-Newton Distant Cluster Project (XDCP). XMMUJ0044.0-2033 was detected at a high significance lev
We report the discovery of a massive, X-ray-luminous cluster of galaxies at z=1.393, the most distant X-ray-selected cluster found to date. XMMU J2235.3-2557 was serendipitously detected as an extended X-ray source in an archival XMM-Newton observati
Most galaxies in clusters have supermassive black holes at their center, and a fraction of those supermassive black holes show strong activity. These active galactic nuclei(AGNs) are an important probe of environmental dependence of galaxy evolution,