Astronomy Seminars

From first stars to supermassive blackholes

by Dr Mahsa Sanati (Chalmers)

Europe/Stockholm
FC61 (AlbaNova Main Building)

FC61

AlbaNova Main Building

Zoom ID: 622 1126 9644; Password : 593083
Description

Evidence supporting the existence of supermassive black holes (SMBHs), which host extremely bright quasars at high redshifts, imposes constraints on the formation and growth of their initial seeds. Recent JWST observations reveal the presence of such SMBHs at even earlier epochs, providing only a few hundred million years for the black hole seeds to accrete gas and grow. The choice of a Eddington limited accretion is a common practice in modelling the growth of SMBH seeds, however, there are numerous uncertainties regarding their accretion during initial stages. We propose a model for the formation of SMBHs from the remnants of a specific class of first stars known as Population III.1 stars, forming within isolated dark matter mini-halos in the early Universe. In this model, SMBHs undergo growth through mergers and gas accretion, with their growth being regulated by AGN feedback. The talk aims to explore the growth and activity of SMBHs forming from Pop III.1 stars in cosmological simulations and the traces of this scenario in the epoch of reionization.