A Cold Channel for Black Hole Accretion in Cosmological Simulations

TYPEAstrophysics Seminar
Speaker:Amit Kashi
Affiliation:Department of Physics and Astronomy, University of Nevada, Las Vegas
Location:Lidow 620

Using 3D cosmological smoothed particle hydrodynamics (SPH) simulations,

we develop a sub-grid model of gas accretion onto supermassive black
holes (SMBH)

that considers the accretion of cold blobs instead of hot gas.

In our simulations, the SMBH accretion rate is not estimated by the
Bondi formula,

but rather based on non-spherical mass supply from cold, gravitationally
bound SPH particles.

We take into account mechanical feedback in a form of outflowing wind
from the material originating from the cold inflow.

The accreted part of the inflowing material liberates energy that heats
the surrounding gas and together with the mechanical feedback affects
the evolution of the host galaxy.

The predicted accretion rate is time-variable and is strongly connected
to both the feedback processes and the availability of cold material.

Our model can account for the expected BH mass density, the cosmic star
formation rate density, and other cosmological properties.