Description:

Black hole science has entered into a particularly exciting era characterized by groundbreaking current and future international missions like the Event Horizon Telescope (EHT), the GRAVITY Interferometer, LIGO, pulsar timing arrays, ngEHT and LISA. Understanding the electromagnetic counterparts to black hole systems generally requires a detailed understanding of complex plasma and accretion dynamics (what Abramowicz & Fragile call "the dirty astrophysical parts"). In this talk I will summarize our efforts to understand these "dirty astrophysical parts" (i.e, accretion and the associated electromagnetic emission) using novel approaches in 3D numerical simulations. First I will describe a method to connect global simulations to microphysical simulations of fundamental plasma physics for modeling EHT targets Sagittarius A* and M87* while highlighting some specific applications. Then I will showcase several results from multiscale simulations of Sagittarius A* that connect the event horizon-scale to the stellar wind feeding scale (bridging over 5 orders of magnitude in radius). Finally, I will present an exciting and computationally efficient new way to simulate binary black hole accretion in gravitational wave-emitting systems relevant for LISA and pulsar timing arrays.  

Sean Ressler, Post-doctoral Fellow, Canadian Institute for Theoretical Astrophysics, University of Toronto

Host: Elena Murchikova