Clusters of galaxies as a tool in cosmology

Abstract

Using the data comprising measurements of the gas mass fraction fgas for 42 hot and dynamically relaxed galaxy clusters with redshift spanning the range of 0:05 < z < 1:1, collected and analysed by Allen (2008) from the Chandra X-ray observations, we obtained constraints on the matter density parameter m and baryonic matter density parameter b. In our calculations, we took into account two most popular cosmological scenarios: quintessence model in which dark energy equation of state is constant and the model in which cosmic equation of state evolves with redshift according to Chevalier–Polarski–Linder (CPL) parametrization. Our results for quintessence model: m = 0:301 0:086, b = 0:042 0:011 as well as for time-varying CPL scenario: m = 0:268 0:094, b = 0:038 0:012 are in a very good agreement with the latest Planck results. This demonstrates that galaxy clusters can be an excellent tool to constrain the values of relevant cosmological parameters.