On (Not)-Constraining Heavy Asymmetric Bosonic Dark Matter

TL;DR

This paper challenges previous constraints on heavy bosonic asymmetric dark matter by showing that such particles form small black holes that evaporate quickly, preventing star destruction and invalidating earlier mass-based limits.

Contribution

It demonstrates that constraints on dark matter masses above a few TeV are not valid because collapsing particles form evaporating black holes instead of destroying stars.

Findings

Heavy dark matter forms small black holes that evaporate rapidly.

No star destruction occurs for dark matter masses above a few TeV.

Previous constraints do not apply to heavy bosonic asymmetric dark matter.

Abstract

Recently, constraints on bosonic asymmetric dark matter have been imposed based on the existence of old neutron stars excluding the dark matter masses in the range from $\sim 2$ keV up to several GeV. The constraints are based on the star destruction scenario where the dark matter particles captured by the star collapse forming a black hole that eventually consumes the host star. In addition, there were claims in the literature that similar constraints can be obtained for dark matter masses heavier than a few TeV. Here we argue that it is not possible to extend to these constraints. We show that in the case of heavy dark matter, instead of forming a single large black hole that consumes the star, the collapsing dark matter particles form a series of small black holes that evaporate fast without leading to the destruction of the star. Thus, no constraints arise for bosonic asymmetric dark matter particles with masses of a few TeV or higher.