Supermassive black holes from runaway mergers and accretion in nuclear star clusters

Konstantinos Kritos; Emanuele Berti; Joseph Silk

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arXiv · 2404.11676

Supermassive black holes from runaway mergers and accretion in nuclear star clusters

Konstantinos Kritos·Emanuele Berti·Joseph Silk

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Abstract

Rapid formation of supermassive black holes occurs in dense nuclear star clusters that are initially gas-dominated. Stellar-mass black hole remnants of the most massive cluster sink into the core, where a massive runaway black hole forms as a consequence of combined effects of repeated mergers and Eddington-limited gas accretion. The associated gravitational wave signals of high-redshift extreme mass-ratio inspirals are a unique signature of the nuclear star cluster scenario.

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Konstantinos Kritos, Emanuele Berti, Joseph Silk. 2024-04-17. Supermassive black holes from runaway mergers and accretion in nuclear star clusters. https://arxiv.org/abs/2404.11676

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