Astronomy and Astrophysics – Astronomy
Scientific paper
Aug 2007
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2007apj...665..107p&link_type=abstract
The Astrophysical Journal, Volume 665, Issue 1, pp. 107-119.
Astronomy and Astrophysics
Astronomy
44
Cosmology: Theory, Galaxies: Active, Galaxies: Evolution, Galaxies: Formation, Hydrodynamics, Galaxies: Quasars: General
Scientific paper
We investigate the physical conditions for the growth of intermediate-mass seed black holes assumed to have formed from remnants of the first generation of massive stars. We follow the collapse of high σ halos with Tvir>104 K using cosmological, smooth-particle hydrodynamic (SPH) simulations in the standard ΛCDM model. During the collapse of the parent halo, the seed holes are incorporated through mergers into larger systems and accrete mass from the surrounding gas. We include a self-consistent treatment of star formation, black hole accretion, and associated feedback processes. Even under optimistic assumptions for the seed black hole mass and for efficient merger rates, we find that seed holes in halos M<=1010 Msolar never reach the conditions for critical Eddington growth. Most of the black hole growth in this regime is determined by the initial mass and the merger rates. Critical accretion rates are reached, albeit only after a significant delay, at the time of collapse (z~7) for 3-4 σ halos of M~1011 Msolar. Our results imply MBH=5×106 Msolar(Mhalo/1011 Msolar)0.78 at the time of collapse. The required conditions of Eddington growth to explain the buildup of supermassive black holes (~109 Msolar), as implied by Sloan quasars at z>6, are therefore hard to meet in such a scenario. Without a ``jump start,'' these conditions may be only achieved in extremely rare halos with Mhalo>1013 that collapsed before z~6. The sub-Eddington regime in which black holes accrete at early time implies a small contribution to the reionization by miniquasar but still sufficient to cause appreciable heating of the IGM at z<~15-18.
Ciardi Benedetta
Di Matteo Tiziana
Pelupessy Federico I.
No associations
LandOfFree
How Rapidly Do Supermassive Black Hole ``Seeds'' Grow at Early Times? does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with How Rapidly Do Supermassive Black Hole ``Seeds'' Grow at Early Times?, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and How Rapidly Do Supermassive Black Hole ``Seeds'' Grow at Early Times? will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-959173