Friday, October 20, 2023 at 12:15 pm

JILA Foothills Room

Hannalore Gerling-Dunsmore, CU Boulder

"Impact of Intermediate Accretion Scales and Multiphysics on SMBH Growth and Outer Disk Stability In the Early Universe"

Abstract:

The formation of supermassive black holes (SMBHs) and the rapid fueling of active galactic nuclei (AGN) in the early universe are two of the biggest mysteries in astrophysics. Previously, it was believed that AGN had up to 1 Gyr to form; with the observation capabilities of JWST, this has been reduced to approximately 350 Myr. In order to determine how AGN form so quickly and can launch the observed powerful outflows, several major problems in accretion theory must be solved. A few of the most important of these problems are accretion disk stability against self-gravity, capture of matter from the surrounding environment onto the accretion disk, and rapid transport of matter through the disk.

In this talk, I will present two sets of preliminary results, both from simulations using Athena++. The first set of results is from a series of 3D MHD shearing box simulations investigating the interaction of the magnetorotational instability (MRI) and self- gravity in the outer disk (~1 pc), and the impact on suppressing fragmentation in the outer disk. The second set of results is from a series of 2D radiation-hydrodynamics simulations of the mid to outer accretion disk. This study investigates the impact of radiation on capturing matter from the surrounding environment into the accretion disk of rapidly growing SMBH seeds, as well as on the mass inflow rate and the strength of the radiative outflows launched back into the forming host galaxy. This informs how much radiative energy can be expected to heat the outer disk and the magnitude of inflow rates from the environment, both of which are expected to aid in the suppression of fragmentation in the gravitationally unstable region. I will then discuss future work, including implications for LIGO and LISA.

Back to Speakers