Super-Eddington Accretion and Feedback from the First Massive Seed Black Holes. (arXiv:1811.04953v1 [astro-ph.GA])
<a href="http://arxiv.org/find/astro-ph/1/au:+Regan_J/0/1/0/all/0/1">John A. Regan</a> (Dublin City University), <a href="http://arxiv.org/find/astro-ph/1/au:+Downes_T/0/1/0/all/0/1">Turlough P. Downes</a> (Dublin City University), <a href="http://arxiv.org/find/astro-ph/1/au:+Volonteri_M/0/1/0/all/0/1">Marta Volonteri</a> (IAP), <a href="http://arxiv.org/find/astro-ph/1/au:+Beckmann_R/0/1/0/all/0/1">Ricarda Beckmann</a> (IAP), <a href="http://arxiv.org/find/astro-ph/1/au:+Lupi_A/0/1/0/all/0/1">Alessandro Lupi</a> (IAP), <a href="http://arxiv.org/find/astro-ph/1/au:+Trebitsch_M/0/1/0/all/0/1">Maxime Trebitsch</a> (IAP), <a href="http://arxiv.org/find/astro-ph/1/au:+Dubois_Y/0/1/0/all/0/1">Yohan Dubois</a> (IAP)
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 a
free-fall time, thereby creating a feedback loop where high accretion rates
generate strong outflows which temporarily suppress further accretion. 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 10,000 required for the seeds to become the SMBHs observed at $z>6$.
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 a
free-fall time, thereby creating a feedback loop where high accretion rates
generate strong outflows which temporarily suppress further accretion. 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 10,000 required for the seeds to become the SMBHs observed at $z>6$.
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