Characterization of Intracluster Medium Temperature Distributions of 62 Galaxy Clusters with XMM-Newton
Abstract
We measure the intracluster medium (ICM) temperature distributions for 62 galaxy clusters in the HIFLUGCS, an X-ray flux-limited sample, with available X-ray data from XMM-Newton. We search for correlations between the width of the temperature distributions and other cluster properties, including median cluster temperature, luminosity, size, presence of a cool core, active galactic nucleus (AGN) activity, and dynamical state. We use a Markov Chain Monte Carlo analysis, which models the ICM as a collection of X-ray emitting smoothed particles of plasma. Each smoothed particle is given its own set of parameters, including temperature, spatial position, redshift, size, and emission measure. This allows us to measure the width of the temperature distribution, median temperature, and total emission measure of each cluster. We find that none of the clusters have a temperature width consistent with isothermality. Counterintuitively, we also find that the temperature distribution widths of disturbed, non-cool-core, and AGN-free clusters tend to be wider than in other clusters. A linear fit to σ kT -kT med finds σ kT ~ 0.20kT med + 1.08, with an estimated intrinsic scatter of ~0.55 keV, demonstrating a large range in ICM thermal histories.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- February 2013
- DOI:
- 10.1088/0004-637X/764/1/46
- arXiv:
- arXiv:1212.2239
- Bibcode:
- 2013ApJ...764...46F
- Keywords:
-
- galaxies: clusters: general;
- galaxies: clusters: intracluster medium;
- X-rays: galaxies: clusters;
- Astrophysics - Cosmology and Extragalactic Astrophysics
- E-Print:
- 22 pages, 16 figures, accepted to ApJ