Accretion onto Intermediate-mass Seed Black Holes in Primordial Galaxies
  The origin of the supermassive black holes that power the most distant
quasars observed is largely unknown. One hypothesis is that they grew rapidly
from intermediate-mass seeds (~100 M_sun) left by the first stars. However,
some previous studies argued that accretion onto these black holes was too low
to build up the mass due to strong suppression by radiative feedback. Here, we
re-exam the accretion process of such a black hole embedded in a primordial gas
cloud, by considering a wide range of physical and numerical parameters not
explored before. We find that, while radiative heating and pressure indeed
suppress accretion effectively, self-gravity of the gas eventually overcomes
the feedback effects and boosts the accretion to the Eddington rate after one
free-fall timescale of the cloud. Moreover, for a given black hole mass, there
exists a critical density above which the accretion can reach Eddington limit.
Furthermore, we find a universal correlation between black hole accretion rate
and ambient gas density, which may serve as a realistic recipe for black hole
growth in simulations.
