Dark Matter Search

¡¡¡¡A popular DM candidate is the so-called weakly interacting massive particle(WIMP). In general, there are three kinds of detection experiments for WIMP, namely collider detection, direct detection, and indirect detection. The indirect detection searches for the DM annihilation or decay products in high energy cosmic-rays (CRs). The future observations of HERD will be able to detect the possible DM signals in high energy CR electrons/positrons and gamma-rays spectra.

¡¡¡¡Positron excess, compared with the ordinary expectation of the CR physics, in the CR flux have been reported by PAMELA and very precisely measured by AMS-02 in an extended energy range up to TeV. A variety of theoretical studies focusing on the DM interpretation of this excess have been performed in the literature, however the origin of these high energy positrons remain debatable.

¡¡¡¡In order to distinguish the origin of the high energy electrons/positrons, either from DM annihilation or from astrophysical sources, the observed electron-positron spectrum at higher precision and higher energy scales is very important. The Chinese satellite experiment DAMPE has measured the electron spectrum and has shown some interesting spectral features at ¡«TeV. Compared with DAMPE, the HERD experiment has a larger acceptance, and can measure the electron-positron spectrum with higher precision and at higher energy. Therefore, the future HERD measurement of CR electrons/positrons will be important for high energy astrophysics and DM studies