Supermassive Black Hole Growth and Environmental Effects in TNG100 simulation

Kate Kireyeva
Dr. Colin DeGraf, Faculty Mentor

Supermassive black holes (BHs) typically follow a tight scaling relation with their hosts; however, some BHs appear to be "overmassive", meaning their mass significantly exceeds what is expected based on their host galaxy. We investigate the growth of these BHs using the IllustrisTNG cosmological simulation (TNG100) at z = 0, quantifying BH growth channels and their dependence on host galaxy and halo environment. We find that BH mergers become increasingly important in BH growth at higher masses (above 6.5 × 10^8 solar masses), with major BH mergers (>1:4 mass ratio) contributing up to 45% of the total BH mass and triggering a slight increase in Eddington ratio. Overmassive BHs are more commonly found in massive halos and near halo centers, and are typically hosted by quenched galaxies with low specific star formation rates, suggesting a strong connection to environmental processes.

Keywords: Supermassive black holes, Black hole growth, Galaxy evolution, IllustrisTNG

Topic(s):Astronomy
Physics

Presentation Type: Oral Presentation

Session: TBA
Location: TBA
Time: TBA