Astrophysics and cosmology with the mass distribution of gravitational wave sources

The growing catalog of gravitational wave signals from merging neutron stars and black holes is gradually illuminating features in the underlying population of these compact objects. This astrophysical distribution contains signatures of the processes that lead to the formation of merging compact objects, as well as the conditions of the universe through which the gravitational waves propagated before reaching earth. It is therefore a powerful tool both for measuring cosmological parameters as well as for understanding both the astrophysics of compact object formation. I will present two recent insights into the mass distributions of these extreme objects, and discuss how we can use it for clean cosmological measurements.

With ~90 sources in the most recent gravitational wave catalog and hundreds more on the way from LIGO, Virgo, and KAGRA’s current observing run, population analyses such as these will become increasingly informative and important.