Probing black hole formation through the observed population of binary black hole mergers

Following the first observation of gravitational waves in 2015, we have now observed close to 100 signals from merging black holes and neutron stars. These observations have enabled us to begin to identify, often unexpected, properties in the black hole population. For example, we are beginning to see the emergence of structure in the observed black hole mass distribution, as well as hints that black hole masses and spins are correlated.

This PhD project involves developing and improving techniques to infer the properties of the black hole population from the observed gravitational wave signals. In spring 2023, the LIGO, Virgo and KAGRA observatories will begin their fourth observing run, which is expected to yield several new observations of black hole mergers each week.

This PhD project will make use of these observations, to more accurately extract astrophysical distributions of black holes in the universe. It will then investigate how better understanding the mass, mass-ratio, spin and eccentricity of black holes in merging binaries can be used to probe the astrophysical formation mechanisms of black hole binaries. Towards the end of the PhD, the observatories are expected to begin their fifth observing run, with daily observations of gravitational wave signals. This will provide an opportunity to test any predictions that have been made and further improve our astrophysical understanding of black holes.