Intermediate mass black holes and dark matter at the Galactic center

TL;DR

This paper explores the possibility that a population of intermediate-mass black holes and dark matter at the Galactic center could explain the observed gamma-ray excess through dark matter annihilations, suggesting a link between black hole formation and dark matter distribution.

Contribution

It proposes that relic intermediate-mass black holes and dark matter density spikes could account for the Fermi gamma-ray excess in the Galactic center.

Findings

Relic IMBHs and dark matter spikes can produce gamma-ray signals consistent with observations.

Survival of dark matter density spikes around IMBHs is plausible.

IMBHs could seed early galaxy and black hole formation.

Abstract

Could there be a large population of intermediate-mass black holes (IMBHs) formed in the early universe? Whether primordial or formed in Population III, these are likely to be very subdominant compared to the dark matter density, but could seed early dwarf galaxy/globular cluster and supermassive black hole formation. Via survival of dark matter density spikes, we show here that a centrally concentrated relic population of IMBHs, along with ambient dark matter, could account for the Fermi gamma-ray "excess" in the Galactic center because of dark matter particle annihilations.