TAPIR Seminar

In person: 370 Cahill. To Join via Zoom: 851 0756 7442

Abstract: Study of stellar objects embedded in AGN accretion disks has been motivated by i) the disk(s) of stars that possibly formed in-situ in the galactic center; ii) the super-solar metallicity of classical quasars independent of redshift, as well as possible AGN+star origin of Little Red Dots; iii) quasi-periodic eruptions connected to star-disk collisions, and iv) LIGO-Virgo gravitational wave sources potentially born in gas rich environments. In this talk, I will introduce some recent progress on how we apply frameworks of planetary astrophysics to study stellar evolution in AGN disks - "magnified" version of planetary disks,  focusing on what we learn about the accretion process of embedded massive stars from radiation hydrodynamic simulations, and how tidal interaction and turbulence influences the spin and migration of AGN-embedded compact objects. I will also introduce some recent studies on formation of sub-solar neutron stars in collapsar disks - "miniaturized" versions of planetary disks - and their associated multi-messenger signals, demonstrating how creation of orbital systems across vastly different cosmic scales can follow similar physical principles.