The peculiar velocity and temperature profile of galaxy clusters

Abstract

Dynamical parameters like average velocity dispersion and temperature profile of galaxy clusters are determined using a quasi equilibrium thermodynamic theory. The calculated velocity dispersion results from theory and simulations shows a good agreement with the velocity dispersion results of (Abdullah et al. \cite{Abd11}). An Adaptive Mesh Refinement (AMR), Grid based hybrid code have been used to carry out the simulations. Our results indicate that the average velocity dispersion profile of $20$ Abell galaxy clusters falls in the range of $500-1000$ km/s and their temperature profile is of the order of $10^7$ to $10^8$K calculated on the basis of kinetic theory. The data in the plot shows a significant contribution of gravitating particles clustering together in the vicinity of cluster center and beyond a certain region this velocity dies out and gets dominated by the Hubble's flow due to which all the galaxy clusters in an expanding universe participate in Hubble's expansion.