MOCCA-SURVEY Database - I. Coalescing binary black holes originating from globular clusters

In this first of a series of papers, we utilize results for around 2000 star cluster models simulated using the MOCCA code for star cluster evolution (Survey Database I) to determine the astrophysical properties and local merger rate densities for coalescing binary black holes (BBHs) originating from globular clusters (GCs). We extracted information for all coalescing BBHs that escape the cluster models and subsequently merge within a Hubble time along with BBHs that are retained in our GC models and merge inside the cluster via gravitational wave emission. By obtaining results from a substantial number of realistic star cluster models that cover different initial parameters, we have an extremely large statistical sample of BBHs with stellar mass and massive stellar BH (less than or similar to 100M(circle dot)) components that merge within a Hubble time. Using these data, we estimate local merger rate densities for these BBHs originating from GCs to be at least 5.4 Gpc(- 3) yr(-1).