Neutron star as a complementary probe to particle dark matter

Yen-Hsun Lin^1*, Chian-Shu Chen²

¹Department of Physics, National Cheng Kung University, Tainan, Taiwan
²Department of Physics, Tamkang University, New Taipei, Taiwan

* Presenter:Yen-Hsun Lin, email:yenhsun@phys.ncku.edu.tw

Compact stellar objects such as neutron stars (NS) are ideal places for capturing dark matter (DM) particles even the interaction between DM and the visible sector is puny. When a significant amount of DM accumulates in the center of the NS, it triggers annihilation with an appreciated rate. The final annihilation products could be reabsorbed by the surrounding medium and prevents the host NS from inevitable cooling. We are able to constraint the DM-nucleon cross section σ_χn by observing the NS surface temperature. Even DM does not annihilate, the lasting capture of DM particles in the NS can cause them forming a black hole and consumes the entire star. Any NS survives for billions of years can set a bound on DM lifetime τ. Thus, with such features, by searching old NS can act as a complementary probe to DM properties besides the current direct detections and other astrophysical observations.

Keywords: dark matter, neutron star, self-interaction