Consequences of neutron decay inside neutron stars

TL;DR

This paper investigates how neutron decay into dark matter within neutron stars affects their structure and rotation, suggesting strong dark matter self-interactions are necessary to match observed star masses.

Contribution

It introduces a novel approach to test neutron decay into dark matter using neutron star observations and predicts observable effects like star heating and increased rotation speed.

Findings

Neutron decay into dark matter impacts neutron star properties.

Strong dark matter self-interactions are required for observed star masses.

Neutron stars may experience heating and spin-up due to decay processes.

Abstract

The hypothesis that neutrons might decay into dark matter is explored using neutron stars as a testing ground. It is found that in order to obtain stars with masses at the upper end of those observed, the dark matter must experience a relatively strong self-interaction. Conservation of baryon number and energy then require that the star must undergo some heating, with a decrease in radius, leading to an increase in speed of rotation over a period of days.