Dark Matter Accretion into Supermassive Black Holes

Abstract

The relativistic accretion rate of dark matter by a black hole is revisited. Under the assumption that the phase space density indicator, $Q={\rho }_{\infty }/{\sigma }_{\infty }^3$, remains constant during the inflow, the derived accretion rate can be higher up to five orders of magnitude than the classical accretion formula, valid for non-relativistic and non-interacting particles, when typical dark halo conditions are considered. For these typical conditions, the critical point of the flow is located at distances of about 30-150 times the horizon radius. Application of our results to black hole seeds hosted by halos issued from cosmological simulations indicate that dark matter contributes to no more than ~10% of the total accreted mass, confirming that the bolometric quasar luminosity is related to the baryonic accretion history of the black hole.

7 pages, 6 figures. Accepted for publication in Phys.Rev.D

References in corpus (2)

• Critical properties of spherically symmetric black hole accretion in Schwarzschild geometry
• The influence of dark matter halo onto the evolution of a supermassive black hole

Cited by in corpus (1)

• Excised black hole spacetimes: quasi-local horizon formalism applied to the Kerr example