부산대학교 도서관

Here we discuss the X-ray properties of clusters of galaxies optically selected in the Red-Sequence Cluster Survey (RCS) observed with the Chandra satellite, at redshifts 0.6 < z < 1.2. We intended to assess the evolutionary stage of optically selected high-z clusters of galaxies, performing a spectral analysis of the diffuse emission from their ICM. We also investigated the distribution of AGN in their surroundings. The background subtracted spectra were analyzed and fitted with a single temperature model to measure average ICM temperature, X-ray bolometric luminosity and Fe abundance within typical radii between 200 and 350 kpc. We also analyzed the point source number density and spatial distribution in the RCS clusters fields as a function of the X-ray flux. We detected emission for the majority of the clusters, except for three, for which we have only marginal detection at ~3 Sigma. We find that the normalization of the L-T relation for RCS clusters is a factor of ~2 lower than the one for X-ray selected clusters. We confirm that the Fe abundance in the detected objects is consistent with that of X-ray selected clusters at the same redshift. We also found an excess of low-luminosity AGN towards the center of the clusters.
Comment: 16 pages, 12 figures, accepted for publication in A&A