Dynamical formation of black hole binaries in dense star clusters: the Rapster code

Gravitational-wave observations have just started probing the properties of black hole binary merger populations. The observation of binaries with very massive black holes and significantly asymmetric masses motivates the study of dense star clusters as astrophysical environments which can produce such events dynamically. In this paper we present Rapster (for "Rapid cluster evolution"), a new code designed to rapidly model binary black hole population synthesis and the evolution of massive star clusters based on simple, yet realistic prescriptions. We also perform a thorough comparison with the Cluster Monte Carlo code and find generally good agreement. The code can be used to generate large populations of dynamically formed binary black holes.
Comment: 34 pages, 10 figures, 1 table. Manuscript and code significantly revised in response to the referees' comments. The Rapster code and data are publicly available at https://github.com/Kkritos/Rapster and https://zenodo.org/records/10626210