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arXiv · 2410.24224

What is the origin of the JWST SMBHs?

John Ellis·Malcolm Fairbairn·Juan Urrutia·Ville Vaskonen
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Abstract

We present a new semi-analytical model for the evolution of galaxies and supermassive black holes (SMBHs) that is based on the extended Press-Schechter formalism and phenomenological modelling of star formation. The model yields BH mass-stellar mass relations that reproduce both the JWST and pre-JWST observations. If the efficiency for BH mergers is high the JWST data prefer light seeds while the pre-JWST data prefers heavy seeds. The fit improves for a smaller merger efficiency, $O(0.1)$, for which both data prefer heavy seeds, while also accommodating the PTA GW background data.

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John Ellis, Malcolm Fairbairn, Juan Urrutia, Ville Vaskonen. 2024-10-31. What is the origin of the JWST SMBHs?. https://doi.org/10.1051/0004-6361%2F202555389

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