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arXiv · 0809.5077

Application of a Self-Similar Pressure Profile to Sunyaev-Zel'dovich Effect Data from Galaxy Clusters

T. Mroczkowski·M. Bonamente·J. E. Carlstrom·T. L. Culverhouse·C. Greer·D. Hawkins·R. Hennessy·M. Joy·J. W. Lamb·E. M. Leitch·M. Loh·B. Maughan·D. P. Marrone·A. Miller·D. Nagai·S. Muchovej·C. Pryke·M. Sharp·D. Woody
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Abstract

We investigate the utility of a new, self-similar pressure profile for fitting Sunyaev-Zel'dovich (SZ) effect observations of galaxy clusters. Current SZ imaging instruments - such as the Sunyaev-Zel'dovich Array (SZA) - are capable of probing clusters over a large range in physical scale. A model is therefore required that can accurately describe a cluster's pressure profile over a broad range of radii, from the core of the cluster out to a significant fraction of the virial radius. In the analysis presented here, we fit a radial pressure profile derived from simulations and detailed X-ray analysis of relaxed clusters to SZA observations of three clusters with exceptionally high quality X-ray data: A1835, A1914, and CL J1226.9+3332. From the joint analysis of the SZ and X-ray data, we derive physical properties such as gas mass, total mass, gas fraction and the intrinsic, integrated Compton y-parameter. We find that parameters derived from the joint fit to the SZ and X-ray data agree well with a detailed, independent X-ray-only analysis of the same clusters. In particular, we find that, when combined with X-ray imaging data, this new pressure profile yields an independent electron radial temperature profile that is in good agreement with spectroscopic X-ray measurements.

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T. Mroczkowski, M. Bonamente, J. E. Carlstrom, T. L. Culverhouse, C. Greer, D. Hawkins, R. Hennessy, M. Joy, J. W. Lamb, E. M. Leitch, M. Loh, B. Maughan, D. P. Marrone, A. Miller, D. Nagai, S. Muchovej, C. Pryke, M. Sharp, D. Woody. 2009-01-15. Application of a Self-Similar Pressure Profile to Sunyaev-Zel'dovich Effect Data from Galaxy Clusters. https://doi.org/10.1088/0004-637x%2F694%2F2%2F1034

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