Constraining Fermionic Dark Matter with Galactic Neutron Stars

TL;DR

This paper explores how massive fermionic dark matter particles interact with neutron stars, considering their motion and self-annihilation, to better constrain dark matter properties using pulsar observations.

Contribution

It extends previous bosonic dark matter studies by analyzing fermionic dark matter in neutron stars, incorporating galactic motion and self-annihilation effects for the first time.

Findings

Constraints on DM mass and scattering cross-section derived from pulsar data.

Impact of neutron star motion on dark matter capture rates.

Effects of DM self-annihilation on accumulation inside neutron stars.

Abstract

Dark matter (DM) remains one of the most significant open questions in modern physics, with its nature and interactions largely unexplored. In this study, we investigate the behavior of massive fermionic DM particles in the context of neutron stars (NSs), extending prior studies which focused on the bosonic DM. By incorporating the motion of NSs in the Galaxy and considering scenarios with and without DM self-annihilation, we demonstrate their impact on the DM capture rate and the accumulation process inside NSs. Observational data from pulsars in the Milky Way are used to place constraints on DM properties, including the mass and the DM-nucleon scattering cross-section, offering a more comprehensive picture in probing DM interactions in astrophysical environments.