An investigation of the environmental effects on the merger rates in galaxy clusters

Abstract

I present a study of the merger rate of galaxies in various cluster environments. Mergers are thought to be an important process in galaxy formation and evolution. The frequency of mergers in clusters is disputed, but they are thought to create the large elliptical galaxies found at the centers of clusters, brightest cluster galaxies (BCGs). I study how the cluster environment influences the formation of BCGs through the use of N-body simulations containing different numbers of galaxies. Merger rates will depend on the cluster environment: a higher cluster mass reflects a deeper potential well and a greater velocity dispersion. This decreases the chance of a collision resulting in a merger. This study investigates the merger rate of galaxies along with other properties such as mass evolution, radial distribution and velocity dispersion of the galaxies within the cluster, and the formation of BCGs. I find that mergers occur less frequently in larger clusters.