Thermalization and Annihilation of Dark Matter in Neutron Stars

Understand

The capture of dark matter, and its subsequent annihilation, can heat old, isolated neutron stars.

• In order for kinetic heating to be achieved, the captured dark matter must undergo sufficient scattering to deposit its kinetic energy in the star.
• We find that this energy deposit typically occurs quickly, for most of the relevant parameter space.
• In order for appreciable annihilation heating to also be achieved, the dark matter must reach a state of capture-annihilation equilibrium in the star.