Super-Eddington Accretion and Feedback from the First Massive Seed Black
  Holes
  Super-Eddington accretion onto massive black hole seeds may be commonplace in
the early Universe, where the conditions exist for rapid accretion. Direct
collapse black holes are often invoked as a possible solution to the
observation of super massive black holes (SMBHs) in the pre-reionisation
Universe. We investigate here how feedback, mainly in the form of bipolar jets,
from super-Eddington accreting seed black holes will affect their subsequent
growth. We find that, nearly independent of the mass loading of the bipolar
jets, the violent outflows generated by the jets evacuate a region of
approximately 0.1 pc surrounding the black hole seed. However, the jet outflows
are unable to break free of the halo and their impact is limited to the
immediate vicinity of the black hole. The outflows suppress any accretion for
approximately a dynamical time. The gas then cools, recombines and falls back
to the centre where high accretion rates are again observed. The overall effect
is to create an effective accretion rate with values of between 0.1 and 0.5
times the Eddington rate. If this episodic accretion rate is maintained for
order 500 million years then the black hole will increase in mass by a factor
of between 3 and 300 but far short of the factor of $10^4$ required for the
seeds to become the SMBHs observed at $z>6$. Therefore, direct collapse black
holes born into atomic cooling haloes and which experience strong negative
mechanical feedback will require external influences (e.g. rapid major mergers
with other haloes) to promote efficient accretion and reach SMBH masses within
a few hundred million years.
