  We study how many-body effects alter the dark matter (DM) thermalization time
inside neutron stars. We find that Pauli blocking, kinematic constraints, and
superfluidity and superconductivity in the neutron star significantly affect
the DM thermalization time, in general lengthening it. This could change the
final DM mass and DM-nucleon cross section constraints by considering black
hole formation in neutron stars due to DM accretion. We consider the class of
models in which DM is an asymmetric, complex scalar particle with a mass
between 1 keV and 5 GeV which couples to regular matter via some heavy vector
boson. Interestingly, we find that the discovery of asymmetric, bosonic DM
could motivate the existence of exotic neutron star cores. We apply our results
to the case of mixed sneutrino DM.
