The effects of supernovae on the dynamical evolution of binary stars and star clusters

TL;DR

Supernovae significantly impact binary star orbits and can influence star cluster dynamics, but recent evidence suggests their overall effect on clusters is minimal, while they are a key factor in producing runaway stars.

Contribution

This review synthesizes current understanding of supernova effects on binary systems and star clusters, highlighting recent simulations and observations.

Findings

Supernovae can disrupt binary orbits and produce runaway stars.

Recent simulations show supernovae have minimal impact on star cluster binding.

Runaway stars' velocities align with supernova explosion scenarios.

Abstract

In this chapter I review the effects of supernovae explosions on the dynamical evolution of (1) binary stars and (2) star clusters. (1) Supernovae in binaries can drastically alter the orbit of the system, sometimes disrupting it entirely, and are thought to be partially responsible for `runaway' massive stars - stars in the Galaxy with large peculiar velocities. The ejection of the lower-mass secondary component of a binary occurs often in the event of the more massive primary star exploding as a supernova. The orbital properties of binaries that contain massive stars mean that the observed velocities of runaway stars (10s - 100s km s$^{-1}$) are consistent with this scenario. (2) Star formation is an inherently inefficient process, and much of the potential in young star clusters remains in the form of gas. Supernovae can in principle expel this gas, which would drastically alter the dynamics of the cluster by unbinding the stars from the potential. However, recent numerical simulations, and observational evidence that gas-free clusters are observed to be bound, suggest that the effects of supernova explosions on the dynamics of star clusters are likely to be minimal.