Compact binaries in star clusters - II. Escapers and detection rates

Abstract

We use a self-consistent Monte Carlo treatment of stellar dynamics to investigate black hole binaries that are dynamically ejected from globular clusters in order to determine if they will be gravitational wave sources. We find that many of the ejected binaries initially have short periods and will merge within a Hubble time due to gravitational wave radiation. Thus they are potential sources for ground-based gravitational wave detectors. We estimate the yearly detection rate for current and advanced ground-based detectors and find an enhancement over the rate predicted for binaries produced by pure stellar evolution in galactic fields. We conclude that, in agreement with previous studies, including globular cluster populations is essential for calculating the correct merger detection rates for gravitational wave detection. © 2011 The Authors Monthly Notices of the Royal Astronomical Society © 2011 RAS.