Mergers as a Probe of Particle Dark Matter

TL;DR

This paper proposes a novel mechanism where non-annihilating particle dark matter accumulates in stars, leading to the formation of low mass black holes, which can be tested through cosmic binary merger rate observations.

Contribution

It introduces a new formation pathway for low mass black holes via dark matter accumulation, linking dark matter physics with gravitational wave observations.

Findings

Dark matter can cause stars to collapse into low mass black holes.

The formation mechanism predicts specific signatures in binary merger rates.

Potential observational tests through gravitational wave data.

Abstract

Black holes below Chandrasekhar mass limit (1.4 $M_{\odot}$) can not be produced via any standard stellar evolution. Recently, gravitational wave experiments have also discovered unusually low mass black holes whose origin is yet to be known. We propose a simple yet novel formation mechanism of such low mass black holes. Non-annihilating particle dark matter, owing to their interaction with stellar nuclei, can gradually accumulate inside compact stars, and eventually swallows them to low mass black holes, ordinarily impermissible by the Chandrasekhar limit. We point out several avenues to test this proposal, concentrating on the cosmic evolution of the binary merger rates.