Blue Stragglers and Other Stellar Anomalies: Implications for the Dynamics of Globular Clusters

Abstract

There are several observed phenomena in globular clusters that are thought to be the result of dynamical processes or binary star evolution. This review examines these manifestations of the interaction between globular cluster dynamics and stellar evolution. Blue stragglers may be formed by the evolution of primordial binaries or by collisions. Current evidence suggests that both processes are likely to occur, and that the observed blue straggler sequences can place dynamically interesting limits on rates. Color gradients in globular clusters are thought to be caused by the stripping of giants by collisions, although the creation of blue subdwarfs by the same process may also be required to explain the observations. The observed X-ray sources and radio pulsars are apparently also made by a variety of dynamical processes that are still not fully understood.