Constraining Fermionic Dark Matter with Galactic 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.