Dark, deep, deconfining: Phase transitions in neutron stars as powerful probes of hidden sectors

TL;DR

This paper explores how interactions with hidden sectors could trigger phase transitions in neutron stars, leading to observable phenomena like black holes or gamma-ray bursts, and uses these to set limits on dark matter properties.

Contribution

It introduces a novel mechanism where hidden sector interactions can induce neutron star phase transitions, providing new astrophysical constraints on dark matter.

Findings

Hidden sector interactions can trigger neutron star phase transitions.

Constraints on dark matter interactions are derived from neutron star observations.

Limits on nucleon decay lifetimes are established at around 10^{64} years.

Abstract

The interiors of neutron stars enjoy ideal conditions for the conversion of hadrons to a strange quark phase, theorized to be the stablest form of matter. Though numerous astrophysical means to prompt such a deconfinement phase transition have been suggested, they may be pre-empted by a large energy barrier for nucleation of quark matter droplets. We will show that interactions of hidden sectors of particles with nucleons may surmount the barrier if it exceeds deca-GeV energies, and spark a phase transition. The neutron star would then, depending on the equation of state of QCD matter, convert to a black hole and/or set off a gamma-ray burst (GRB). Using the observed existence of ancient neutron stars and estimates of the GRB rate, we then set some of the strictest (albeit conditional) limits on dark matter scatters, annihilations, and decays that are tens of orders stronger than those from terrestrial searches. For smaller energy barriers, lower limits on nucleon decay lifetimes of the order of $10^{64}$~yr may be obtained