Journal
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
Volume 387, Issue 4, Pages 1649-1659Publisher
OXFORD UNIV PRESS
DOI: 10.1111/j.1365-2966.2008.13344.x
Keywords
accretion, accretion discs; black hole physics; galaxies : nuclei; quasars : general
Categories
Ask authors/readers for more resources
We study the structure and evolution of 'quasi-stars', accreting black holes embedded within massive hydrostatic gaseous envelopes. These configurations may model the early growth of supermassive black hole seeds. The accretion rate on to the black hole adjusts so that the luminosity carried by the convective envelope equals the Eddington limit for the total mass, M-* + M-BH approximate to M-*. This greatly exceeds the Eddington limit for the black hole mass alone, leading to rapid growth of the black hole. We use analytic models and numerical stellar structure calculations to study the structure and evolution of quasi-stars. We show that the photospheric temperature of the envelope scales as T-ph proportional to (MBH-2/5M*7/20), and decreases with time while the black hole mass increases. Once T-ph < 10(4) K, the photospheric opacity drops precipitously and T-ph hits a limiting value, analogous to the Hayashi track for red giants and protostars, below which no hydrostatic solution for the convective envelope exists. For metal-free (Population III) opacities, this limiting temperature is approximately 4000 K. After a quasi-star reaches this limiting temperature, it is rapidly dispersed by radiation pressure. We find that black hole seeds with masses between 10(3) and 10(4) could form via this mechanism in less than a few Myr.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available