Stability and Observability of Magnetic Primordial Black Hole-Neutron Star Collisions

TL;DR

This paper explores how magnetically charged primordial black holes colliding with neutron stars can create observable signals like glitches, and may lead to long-term stable systems without destroying the star.

Contribution

It introduces the concept that magnetic primordial black holes can cause detectable neutron star glitches and form stable configurations, differing from previous destructive models.

Findings

Magnetic black holes rapidly stop in neutron stars and can cause glitches.

Stable equilibrium states can form, preventing complete star destruction.

Neutron star surface properties may change, offering observational signatures.

Abstract

The collision of a primordial black hole with a neutron star results in the black hole eventually consuming the entire neutron star. However, if the black hole is magnetically charged, and therefore stable against decay by Hawking radiation, the consequences can be quite different. Upon colliding with a neutron star, a magnetic black hole very rapidly comes to a stop. For large enough magnetic charge, we show that this collision can be detected as a sudden change in the rotation period of the neutron star, a glitch or anti-glitch.We argue that the magnetic primordial black hole, which then settles to the core of the neutron star, does not necessarily devour the entire neutron star; the system can instead reach a long-lived, quasi-stable equilibrium. Because the black hole is microscopic compared to the neutron star, most stellar properties remain unchanged compared to before the collision. However, the neutron star will heat up and its surface magnetic field could potentially change, both effects potentially observable.