Accretion and Structure of Radiating Disks

TL;DR

This paper models a self-gravitating, radiating, thick accretion disk around supermassive black holes, demonstrating how radiation and accretion influence disk structure in environments like AGN.

Contribution

It introduces a self-consistent numerical scheme for modeling thick accretion disks considering self-gravity, radiation, and mass accretion, with results applicable to AGN environments.

Findings

Disk structures are influenced by radiation and accretion rate.

Configurations match typical AGN parameters with sub-Eddington luminosities.

Results show quasi-Keplerian rotation and significant disk masses.

Abstract

We studied a steadily accreting, geometrically thick disk model that selfconsistently takes into account selfgravitation of the polytropic gas, its interaction with the radiation and the mass accretion rate. The accreting mass is injected inward in the vicinity of the central $z=0$ plane, where also radiation is assumed to be created. The rest of the disk remains approximately stationary. Only conservation laws are employed and the gas-radiation interaction in the bulk of the disk is described in the thin-gas approximation. We demonstrate that this scheme is numerically viable and yields a structure of the bulk that is influenced by the radiation and (indirectly) by the prescribed mass accretion rate. The obtained disk configurations are typical for environments in Active Galactic Nuclei (AGN), with the central mass of the order of $10^7 M_{\astrosun}$ to $10^8 M_{\astrosun}$, quasi-Keplerian rotation curves, disk masses ranging from about $10^6 M_{\astrosun}$ to $10^7 M_{\astrosun}$, and the luminosity ranging from $10^6 L_{\astrosun}$ to $10^9 L_{\astrosun}$. These luminosities are much lower than the corresponding Eddington limit.