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arXiv · 1404.6250

The Redshift Evolution of the Mean Temperature, Pressure, and Entropy Profiles in 80 SPT-Selected Galaxy Clusters

M. McDonald·B. A. Benson·A. Vikhlinin·K. A. Aird·S. W. Allen·M. Bautz·M. Bayliss·L. E. Bleem·S. Bocquet·M. Brodwin·J. E. Carlstrom·C. L. Chang·H. M. Cho·A. Clocchiatti·T. M. Crawford·A. T. Crites·T. de Haan·M. A. Dobbs·R. J. Foley·W. R. Forman·E. M. George·M. D. Gladders·A. H. Gonzalez·N. W. Halverson·J. Hlavacek-Larrondo·G. P. Holder·W. L. Holzapfel·J. D. Hrubes·C. Jones·R. Keisler·L. Knox·A. T. Lee·E. M. Leitch·J. Liu·M. Lueker·D. Luong-Van·A. Mantz·D. P. Marrone·J. J. McMahon·S. S. Meyer·E. D. Miller·L. Mocanu·J. J. Mohr·S. S. Murray·S. Padin·C. Pryke·C. L. Reichardt·A. Rest·J. E. Ruhl·B. R. Saliwanchik·A. Saro·J. T. Sayre·K. K. Schaffer·E. Shirokoff·H. G. Spieler·B. Stalder·S. A. Stanford·Z. Staniszewski·A. A. Stark·K. T. Story·C. W. Stubbs·K. Vanderlinde·J. D. Vieira·R. Williamson·O. Zahn·A. Zenteno
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Abstract

(Abridged) We present the results of an X-ray analysis of 80 galaxy clusters selected in the 2500 deg^2 South Pole Telescope survey and observed with the Chandra X-ray Observatory. We divide the full sample into subsamples of ~20 clusters based on redshift and central density, performing an X-ray fit to all clusters in a subsample simultaneously, assuming self-similarity of the temperature profile. This approach allows us to constrain the shape of the temperature profile over 0 R500) regions than their low-z (0.3 R500 in our high-z subsample. This flattening is consistent with a temperature bias due to the enhanced (~3x) rate at which group-mass (~2 keV) halos, which would go undetected at our survey depth, are accreting onto the cluster at z~1. This work demonstrates a powerful method for inferring spatially-resolved cluster properties in the case where individual cluster signal-to-noise is low, but the number of observed clusters is high.

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M. McDonald, B. A. Benson, A. Vikhlinin, K. A. Aird, S. W. Allen, M. Bautz, M. Bayliss, L. E. Bleem, S. Bocquet, M. Brodwin, J. E. Carlstrom, C. L. Chang, H. M. Cho, A. Clocchiatti, T. M. Crawford, A. T. Crites, T. de Haan, M. A. Dobbs, R. J. Foley, W. R. Forman, E. M. George, M. D. Gladders, A. H. Gonzalez, N. W. Halverson, J. Hlavacek-Larrondo, G. P. Holder, W. L. Holzapfel, J. D. Hrubes, C. Jones, R. Keisler, L. Knox, A. T. Lee, E. M. Leitch, J. Liu, M. Lueker, D. Luong-Van, A. Mantz, D. P. Marrone, J. J. McMahon, S. S. Meyer, E. D. Miller, L. Mocanu, J. J. Mohr, S. S. Murray, S. Padin, C. Pryke, C. L. Reichardt, A. Rest, J. E. Ruhl, B. R. Saliwanchik, A. Saro, J. T. Sayre, K. K. Schaffer, E. Shirokoff, H. G. Spieler, B. Stalder, S. A. Stanford, Z. Staniszewski, A. A. Stark, K. T. Story, C. W. Stubbs, K. Vanderlinde, J. D. Vieira, R. Williamson, O. Zahn, A. Zenteno. 2014-04-24. The Redshift Evolution of the Mean Temperature, Pressure, and Entropy Profiles in 80 SPT-Selected Galaxy Clusters. https://doi.org/10.1088/0004-637x%2F794%2F1%2F67

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