Black hole evolution: from stellar mass to ultra-massive ones

Observations of bright quasars at high-redshift have revealed that supermassive black holes (SMBHs) with billions solar masses already exist only within one billion year after the Big Bang. The discoveries in recent decades provide a challenging puzzle about the origin of SMBHs. In this talk, I will discuss two physical processes to form such monster BHs. The first one is formation of heavy seed BHs due to direct-collapse of massive metal-poor gas clouds in the first galaxies. The second is rapid BH growth at accretion rates exceeding the standard Eddington value. We find global accretion solutions from galactic scales down to the nuclear region at hyper-Eddington rates, unimpeded by radiation feedback. I will apply our results from radiation-hydrodynamical simulations to the cosmological evolution of BHs, and discuss the observational signatures from such bright systems. 

Dr. Kohei Inayoshi
KIAA-PKU Auditorium
Wednesday, January 17, 2018 - 4:00pm to 5:00pm