Effects of Heat Conduction on Blocking off the Super-Eddington Growth of Black Holes at High Redshift
Abstract
We investigate the effect of conductive heating of the gas surrounding a geometrically thick accretion disk on the growth of a black hole (BH) at high redshift. If a BH is accreting the surrounding gas at a super-Eddington rate, the X-ray radiation from the vicinity of the BH would be highly anisotropic due to the self-shielding of a geometrically thick accretion disk, and then the radiative feedback on the surrounding medium would be suppressed in the equatorial region, within which super-Eddington accretion can continue. However, if this region is sufficiently heated via thermal conduction from the adjacent region that is not shielded and heated by the X-ray irradiation, the surrounding gas becomes isotropically hot, and the Bondi accretion rate would be suppressed and become sub-Eddington. We evaluate the condition under which such isotropic heating is realized and derive new criteria required for super-Eddington accretion.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- September 2023
- DOI:
- 10.3847/1538-4357/acee6d
- arXiv:
- arXiv:2304.07184
- Bibcode:
- 2023ApJ...955...67K
- Keywords:
-
- Supermassive black holes;
- Quasars;
- Bondi accretion;
- Accretion;
- 1663;
- 1319;
- 174;
- 14;
- Astrophysics - Cosmology and Nongalactic Astrophysics;
- Astrophysics - High Energy Astrophysical Phenomena
- E-Print:
- 11 pages, 6 figures