Thermodynamic profiles of galaxy cluster gas using a multiwavelength analysis of X-ray and microwave data

The thermal Sunyaev-Zel’dovich (SZ) effect provides a redshift-independent means of measuring gas properties in galaxy clusters, in particular in the outskirts where traditional X-ray studies are least sensitive. This allows a better characterization of cluster physics and tighter constraints on cosmological parameters. Bolocam, a mm-wave imaging camera operated from the Caltech Submillimeter Observatory, was used to study the SZ effect in a sample of 45 clusters with archival Chandra X-ray observations. Gas density and temperature profiles are recovered from a joint fitting method combining thermal SZ maps and X-ray surface brightness profiles. The clusters are modeled individually using smooth analytical profiles and non-parametric onion-skin deprojections. A single joint likelihood function is maximized through a Monte Carlo Markov Chain (MCMC) approach. Ensemble cluster onion-skin profiles are found for the full sample and sub-samples.