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arXiv · 2412.06888

Conditions for Super-Eddington Accretion onto the First Black Holes

Simone T. Gordon·Britton D. Smith·Sadegh Khochfar·Ricarda S. Beckmann
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Abstract

Observations of supermassive black holes at high redshift challenge our understanding of the evolution of the first generation of black holes (BHs) in proto-galactic environments. One possibility is that they grow much more rapidly than current estimates of feedback and accretion efficiency permit. Following our previous analysis of super-Eddington accretion onto stellar-mass black holes in mini-haloes under no-feedback conditions, we now investigate whether this can be sustained when thermal feedback is included. We use four sets of cosmological simulations at sub-pc resolution with initial black hole masses varying from $1 \times 10^3 - 6 \times 10^4 M_\odot$, exploring a range of feedback efficiencies. We also vary the feedback injection radius to probe the threshold of numerical overcooling. We find that super-Eddington growth sustained on the order of $\sim$$100 \, \rm kyr$ is possible with very weak thermal feedback efficiency in all environments and moderate efficiency for two of the BHs. Trans-Eddington growth is possible for a $3 \times 10^3 - 6 \times 10^3 M_\odot$ BH at moderate feedback efficiencies. We discuss the effectiveness of thermal feedback in heating the gas, suppressing accretion, and driving outflows at these parameter configurations. Our results suggest that super-Eddington growth may be possible in the presence of thermal feedback for black holes formed from the first stars.

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Simone T. Gordon, Britton D. Smith, Sadegh Khochfar, Ricarda S. Beckmann. 2024-12-09. Conditions for Super-Eddington Accretion onto the First Black Holes. https://arxiv.org/abs/2412.06888

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