Application of a Self-Similar Pressure Profile to Sunyaev-Zel'dovich Effect Data from Galaxy Clusters
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 a 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.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- April 2009
- DOI:
- 10.1088/0004-637X/694/2/1034
- arXiv:
- arXiv:0809.5077
- Bibcode:
- 2009ApJ...694.1034M
- Keywords:
-
- cosmology: observations;
- galaxies: clusters: individual: Abell 1835 Abell 1914 CL J1226.9+3332;
- X-rays: galaxies: clusters;
- Astrophysics
- E-Print:
- 28 pages, 6 figures, accepted by ApJ for publication (probably April 2009)