Abstract Details
| Name: Kanhaiya Lal Pandey Affiliation: Indian Institute of Astrophysics, Bangalore, India. Conference ID: ASI2018_1743 Title : Role of primordial black holes in SMBH formation at high $z$ Authors and Co-Authors : A. Mangalam; IIA, Bangalore. Abstract Type : Contributed Talk Abstract Category : General Relativity and Cosmology Abstract : We explore the possibility of accreting primordial black holes as the source of heating for the collapsing gas in the context of direct collapse black hole scenario for the formation of super-massive black holes (SMBHs) at high redshifts, $z \simeq 6 -- 7$. An essential requirement for the direct collapse model to work is to maintain the temperature of the infalling gas at $10^4$ K to avoid fragmentation and star formation. We show under the existing abundance limits, that the primordial black holes of masses $\geq10^(-2) M_\odot$, can heat the collapsing gas to an extent that the $H_2$ formation is inhibited. In the absence of $H_2$ cooling, the temperature of the collapsing gas stays at $\sim 10^4$ K even as it collapses further, and thus the collapse can go on without fragmentation and lead to a formation of a super massive disk ($10^(4--5) M_\odot$). We also discuss the physics of the collapse of the viscous disk into a massive seed black hole ($10^(4--5) M_\odot$) which can grow into a SMBH in due time through Eddington limited accretion of surrounding gas. |