Speaker
Description
I will review the evidences in the local universe for star formation caused by jets from accreting black holes (BHs). These BH “positive feedbacks” take place by the interaction of BH-jets with high-density molecular clouds (Dasyra et al. 2022). Because the global gas density in the universe evolves with redshift z as (1+z)^3, it is expected that this star formation mechanism is very important in the early universe, where massive BHs come first and grow faster than stellar populations (e.g.Neeleman et al. 2021).
Recently, has been shown that the SMBHs of 10^9 M⊙ observed in quasars up to z = 7 can result from rapidly growing BH seeds of intermediate masses (IMBHs) of 10^(3-5) M⊙, formed by direct collapse of turbulent cold flows of gas in dark matter haloes at z > 25 (Latif et al. 2022). Growing from z = 30 at Eddington limit with a radiative efficiency of 10%, these IMBH seeds can reach masses of 10^9 M⊙ at z = 7. At z = 30 the global gas density is > 10^4 times the global gas density in the local universe, and under those conditions relativistic jets from those rapidly growing IMBHs would compress the gas triggering the formation of the first massive stars of Pop III.
References:
Dasyra, K. M. et al. 2022, Nature Astronomy 6, 1077-1084
Latif, M.A. et al. 2022, Nature 607, 48–51
Neeleman, M. et al. 2021 ApJ 911, 141
