Is There a Relationship between the Density of Primordial Black Holes in a Galaxy and the Rate of Cosmological Gamma-Ray Bursts?

TL;DR

This paper investigates the potential link between primordial black hole density in galaxies and gamma-ray burst rates, concluding that PBH capture mechanisms are unlikely to account for observed bursts, despite possible high densities.

Contribution

It provides a detailed calculation of PBH capture rates and their independence from PBH mass, challenging their role in gamma-ray burst production.

Findings

Capture rate does not depend on PBH mass.

The mechanism cannot significantly contribute to gamma-ray burst rates.

PBH density can reach the dark matter density in galaxies.

Abstract

The rate of accretion of matter from a solar-type star onto a primordial black hole (PBH) that passes through it is calculated. The probability that a PBH is captured into an orbit around a star in a galaxy is found. The mean lifetime of the PBH in such an orbit and the rate of orbital captures of PBHs in the galaxy are calculated. It is shown that this rate does not depend on the mass of the PBH. This mechanism cannot make an appreciable contribution to the rate of observed gamma-ray bursts. The density of PBHs in the galaxy can reach a critical value - the density of the mass of dark matter in the galaxy.