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The 160 Square Degree ROSAT Survey - Revised Catalog & Cluster Evolution

Christopher Mullis·Brian McNamara·Hernan Quintana·Alexey Vikhlinin·Patrick Henry·Isabella Gioia·Allan Hornstrup·William Forman·Christine Jones
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Abstract

We have constructed a large, statistically complete sample of galaxy clusters serendipitously detected as extended X-ray sources in 647 ROSAT PSPC pointed observations. The survey covers 158 square degrees with a median sample flux limit of 1.2 x 10^-13 erg cm^-2 s^-1 (0.5-2.0 keV). Our sample consists of 201 clusters of galaxies characterized by a median redshift of z=0.25 and a maximum of z=1.26. With 22 clusters at z > 0.5, the 160 Square Degree ROSAT Survey is the largest high-redshift sample of X-ray-selected clusters published to date. Here we describe the revised sample which features spectroscopic redshifts for 99.5% of the clusters and discuss the implications for evolution in the cluster abundance.

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Christopher Mullis, Brian McNamara, Hernan Quintana, Alexey Vikhlinin, Patrick Henry, Isabella Gioia, Allan Hornstrup, William Forman, Christine Jones. 2003-03-19. The 160 Square Degree ROSAT Survey - Revised Catalog & Cluster Evolution. https://arxiv.org/abs/astro-ph/0303438

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