Abstract:

Between the discovery of gravitational waves from over a hundred merging compact objects and the advent of micro-arcsecond astrometry realized by the Gaia space telescope, the study of the complexities of binary stellar evolution – including mass transfer, tides, and r-process nucleosynthesis – has taken on a new urgency. In this talk, I will describe the current status of modeling binary star populations as well as several critical shortcomings that multiple groups throughout the field are working to address. In particular, I will introduce our binary population synthesis code, POSYDON, which combines large grids of MESA simulations with machine learning algorithms to produce the next generation of binary population models. In addition to their implications for the origin of gravitational wave sources, these models promise to improve our interpretation of a wide range of stellar population observations, ranging from nearby open clusters to galaxies at high redshift. Finally, I will speculate on the importance of forthcoming observations to constrain key binary evolution processes.