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Chandra X-ray Observations of Newly Discovered, z ~ 1 Clusters from the Red-Sequence Cluster Survey

Amalia Hicks·Erica Ellingson·Mark Bautz·Howard Yee·Mike Gladders·Gordon Garmire
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Abstract

Observational studies of cluster evolution over moderate redshift ranges (to z ~ 1) are a powerful tool for constraining cosmological parameters, yet a comprehensive knowledge of the properties of these clusters has been hitherto unattained. Using a highly efficient optical selection technique, the Red-Sequence Cluster Survey (RCS) has unearthed a large sample of high redshift cluster candidates. All six of the clusters from this sample which have been observed with the Chandra X-Ray Observatory were detected in the X-ray. These Chandra follow-up observations (0.64 < z < 1.0) indicate that the clusters are systematically less luminous than their similarly rich, X-ray selected counterparts at lower redshifts, though they are consistent with standard Lx-Tx relationships. Comparisons with X-ray selected samples suggest that the discrepancy may be due in part to systematic differences in the spatial structure of the X-ray emitting gas. Our initial results from Chandra follow-up observations of six RCS clusters are presented, including beta model parameters and spectral information.

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Amalia Hicks, Erica Ellingson, Mark Bautz, Howard Yee, Mike Gladders, Gordon Garmire. 2004-10-06. Chandra X-ray Observations of Newly Discovered, z ~ 1 Clusters from the Red-Sequence Cluster Survey. https://arxiv.org/abs/astro-ph/0410167

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