Probing massive binary stars with gravitational waves - Dr Simon Stevenson (Swinburne University)

LIGO, Virgo and KAGRA have unveiled a population of merging neutron star and black hole binaries. The origin of these binaries is currently uncertain; they may be produced by pairs of massive stars evolving via mass transfer episodes, or they may form dynamically in dense stellar environments such as globular clusters or active galactic nuclei, or perhaps some combination of both. We have developed the open-source population synthesis and inference suite COMPAS (https://compas.science)  to model the formation of merging compact object binaries from massive binary stars. COMPAS incorporates several recent developments in population modelling, including an updated treatment of common envelope evolution, improved modelling of chemically homogeneous evolution and a new prescription for winds and tides of massive stars. I will present an overview of predictions for the binary evolution channel utilising these recent updates, and our efforts to use gravitational-wave observations to place constraints on uncertain phases of massive binary stellar evolution.