Title: The seeds of the first supermassive black holes

Place: DAA Seminar. Jeroni Muñoz Research Building, fourth floor, in Campus de Burjassot.

Day: Thursday, january 18, 2024.

Time: 15:00

Abstract:

Supermassive black holes of 10^10 solar masses already existed at z~6-7, when the Universe was less than 1 Gyr old. To reach this mass in such a short time they should have started as seed black holes of <10^6 solar masses at higher redshifts. Hundreds of black holes of 1e5-1e6 Msun have now been found actively accreting in local dwarf galaxies, the building blocks of massive galaxies. Whether these black holes are the ungrown seeds of the first supermassive black holes is difficult to prove, since processes such as galaxy mergers and black hole feedback can have a strong impact on black hole growth. The James Webb Space Telescope has however started to detect a population of black holes in low-mass galaxies at z = 4 − 10 and which could represent the transition from black hole seeds to supermassive black holes.