The properties of merging black holes and neutron stars across cosmic time

Understand

The next generation ground-based gravitational wave interferometers will possibly observe mergers of binary black holes (BBHs) and binary neutron stars (BNSs) to redshift $z\gtrsim{}10$ and $z\gtrsim{}2$, respectively.

• Here, we characterize the properties of merging BBHs, BNSs and neutron star-black hole binaries across cosmic time, by means of population-synthesis simulations combined with the Illustris cosmological simulation.
• We find that the mass of merging compact objects does not depend (or depends very mildly) on the merger redshift.
• Even the mass distribution of black holes depends only mildly on redshift, because BBHs originating from metal-poor progenitors ($Z\leq{}4\times{}10^{-3}$) dominate the entire population of merging BBHs across cosmic time.