Dark matter, neutron stars and strange quark matter

TL;DR

This paper explores how neutralino dark matter accretion onto neutron stars could lead to the formation of strange quark matter, potentially converting neutron stars into strange stars, and sets new limits on WIMP mass.

Contribution

It introduces a novel mechanism linking dark matter accretion to strange quark matter formation in neutron stars, providing new constraints on WIMP properties.

Findings

Dark matter accretion can seed strange quark matter in neutron stars.

Conversion to strange stars depends on WIMP mass and strangelet stability.

New limits on WIMP mass are derived based on strangelet formation energy estimates.

Abstract

We show that self-annihilating neutralino WIMP dark matter accreted onto neutron stars may provide a mechanism to seed compact objects with long-lived lumps of strange quark matter, or strangelets, for WIMP masses above a few GeV. This effect may trigger a conversion of most of the star into a strange star. We use an energy estimate for the long-lived strangelet based on the Fermi gas model combined with the MIT bag model to set a new limit on the possible values of the WIMP mass that can be especially relevant for subdominant species of massive neutralinos.