11-13 November 2019
The University of Tokyo, Kashiwa Campus
Asia/Tokyo timezone

Dark Matter Heating vs. Rotochemical Heating in Old Neutron Stars

12 Nov 2019, 17:20
The University of Tokyo, Kashiwa Campus

The University of Tokyo, Kashiwa Campus

Institute for Cosmic Ray Research, The University of Tokyo, 5-1-5 Kashiwa-no-ha, Kashiwa, Chiba, Japan
Contributed talk DM Astrophysics Young Scientists session


Dr Keisuke Yanagi (University of Tokyo)


WIMP DMs in the Universe accumulate in neutron stars (NSs) through their interactions with nucleons. It has been known that their annihilation inside the NS core causes late-time heating, with which the surface temperature becomes $T_s \simeq (2-3) \times 10^3$ K for the NS age $t > 10^{6-7}$ years. Thus the measurement of NS surface temperature can be used as a new probe of WIMP DMs. Because of the strong gravity of NSs, DM heating has several advantages compared to the direct detection experiments on the earth.

Despite such advantages, the background on the DM heating is rarely discussed in the particle physics community. In particular, the rotochemical heating, internal heating caused by the out-of-equilibrium beta reactions in a NS, should be considered because it does not assume any exotic physics. In fact, if the rotochemical heating operates in a NS, it may conceal the DM heating effects.

In this work, we reevaluate the significance of the DM heating in NSs, including the effect of the rotochemical heating. We show that the signature of DM heating can still be detected in old ordinary pulsars, and discuss what is necessary to confirm the evidence for the DM heating.


University of Tokyo

Primary authors

Prof. Koichi Hamaguchi (University of Tokyo) Dr Natsumi Nagata (University of Tokyo) Dr Keisuke Yanagi (University of Tokyo)

Presentation Materials