Speaker
Description
Old isolated neutron stars have been gathering attention as targets to probe Dark Matter (DM) through temperature observations. DM will anomalously heat neutron stars through its gravitational capture and annihilation process, which predicts $T_s \simeq (1-3) \times 10^3$ K for $t > 10^{6}$ years. We may put constraints on DM-nucleon scattering cross section by finding even colder neutron stars. This story, however, assumed that there is no relevant heating source for old neutron stars. In this talk, we discuss the creep motion of vortex lines in the neutron superfluid of the inner crust as the heating mechanism. This mechanism is inherent in the structure of neutron stars and is expected to be universal. Therefore, in order to constrain DM physics through temperature observations, this mechanism may cause serious background heating. We evaluate the vortex creep heating by inputting the vortex-nucleon interactions and conclude the significance of DM heating in neutron stars.
