Star Cluster Dynamics

Abstract

Many stars are born in clusters arising from the collapse and subsequent fragmentation of giant molecular clouds. During the birth process, radiation pressure from the ignition of bright massive stars and the pressure waves from the following supernovae can sweep away residual mass in the cloud. In some cases, the cluster will become unbound due to the loss of mass. The constituent stars of the cluster are then scattered and they continue to evolve in isolation. Some clusters are more massive and have greater central densities, so that they survive the initial mass loss. In these clusters, even the single stars may not evolve in isolation as they interact with the other stars in the cluster. The archetypical clusters of this type are globular clusters. In this chapter, we will cover some of the basics of modeling the dynamical evolution of these clusters.