Constraints on cluster structure and cosmology from X-ray and Sunyaev-Zel'dovich effect properties of galaxy clusters

We present a study of 36 massive galaxy clusters at redshifts 0.14 ≤ z ≤ 0.89, whose properties are used to constrain cluster structure and cosmological models. The clusters are studied at both X-ray wavelengths using data from the Chandra X-ray Observatory, and at centimeter wavelengths using Sunyaev-Zel`dovich Effect (SZE) data from the BIMA and OVRO interferometric arrays. Likelihood analysis is performed using a Markov chain Monte Carlo (MCMC) method, and we motivate and adopt an isothermal beta-model with central 100 kpc excluded from the X-ray data to describe the intracluster medium in all 36 clusters. This model is shown to provide consistently good fits to clusters with a wide range of morphological properties. Best-fit cluster gas masses, total masses, and integrated SZE fluxes are determined from this model within the MCMC framework. X-ray and SZE results are then used in an effort to constrain cluster structure and cosmology. First, the integrated SZE flux is compared with X-ray derived gas mass, spectroscopic temperature, and total mass to determine how firmly connections between observables and derived cluster properties can be established in SZE surveys. These properties are found to display tight scaling relations over the full range of redshift. Cluster gas mass fractions from both X-ray and SZE data are then compared, and the implications for cluster structure are noted. The gas mass fractions are used to obtain constraints on OM and O Λ both by comparing the mean fgas values to OB/OM for assumed OB, and by assuming that fgas should be constant with redshift and determining what cosmology best facilitates this. Cosmological constraints are found to be consistent with CMB results, but a better understanding of the cluster baryon budget is needed to achieve the same level of precision.