Studying galaxy clusters using the Sunyaev-Zel’dovich effect

Abstract

A well-known way to study clusters of galaxies is the Inverse-Comptonization of Cosmic Microwave Background(CMB) photons by Intra-Cluster medium(ICM), popularly known as Sunyaev-Zel’dovich effect(SZE). For hot ICM gas, relativistic effects must be taken into account. In this work, we have used SZpack1, a numerical library takes into account of these effects and allows high-speed and accurate calculations of SZ signals(0.001% at frequencies≈1000GHz) up to high temperatures(>˜ 75퐾푒푉). We have simulated SZ flux maps of galaxy clusters with a given morphology of thermal electron population and temperature, in order to compare them with actual observations made in cm-wave range using the current generation of radio telescopes. The combination of these simulations and observed data will allow the mapping of pressure in the ICM, which is especially useful for studying the dynamics of cluster mergers