RSN1: Building the Giants: mass assembly, accretion and feedback in high redshift QSOs

Dottorato - Phd Thesis

Area Tematica: RSN 1 - Galassie e cosmologia

Referente: Fabrizio Fiore (This email address is being protected from spambots. You need JavaScript enabled to view it.)
Titolo: Building the Giants: mass assembly, accretion and feedback in high redshift QSOs
Decorrenza: 07.06.2022

Luminous QSOs, powered by accretion onto SMBHs, already exist at the epoch of Reionisation, when the Universe was only 0.5-1 Gyr old. These BH masses are not smaller than those of hyper-luminous QSOs at lower redshift, meaning that BH growth had to be a fast process, and that the process had to stop with a similar high efficiency after the rapid build up. How huge BHs formed and grew-up in such a short time is indeed highly debated, and  it is unknown what slowed down BH growth and when this process occurred, leading towards the symbiotic growth with the host galaxy observed in the local Universe. Candidate processes are inefficient gas accretion and/or feedback through BH winds. At the same time, the host galaxies of high-z QSOs are likely growing rapidly. Therefore, the onset of significant BH feedback hampering BH growth would mark the transition from BH dominance to BH-and-galaxy symbiotic growth phases. We propose a PhD thesis on the subject of the build-up and properties of high redshift QSOs, from the Reionization Epoch (z>6) down to Cosmic Noon (z~2-4). The thesis is observationally-oriented and requires data analysis and interpretation as outlined below.
 
See attached pdf for project details