Ge Shao-Feng, Liu Jianglai, Yuan Qiang, Zhou Ning
Tsung-Dao Lee Institute, Shanghai Jiao Tong University, Shanghai 200240, China.
School of Physics and Astronomy, Shanghai Jiao Tong University, Key Laboratory for Particle Astrophysics and Cosmology (MOE) and Shanghai Key Laboratory for Particle Physics and Cosmology, Shanghai 200240, China.
Phys Rev Lett. 2021 Mar 5;126(9):091804. doi: 10.1103/PhysRevLett.126.091804.
We point out a new type of diurnal effect for the cosmic ray boosted dark matter (DM). The DM-nucleon interactions not only allow the direct detection of DM with nuclear recoils but also allow cosmic rays to scatter with and boost the nonrelativistic DM to higher energies. If the DM-nuclei scattering cross sections are sufficiently large, the DM flux is attenuated as it propagates through the Earth, leading to a strong diurnal modulation. This diurnal modulation provides another prominent signature for the direct detection of boosted sub-GeV DM, in addition to signals with higher recoil energy.
我们指出了宇宙射线增强暗物质（DM）的一种新型日效应。暗物质与核子的相互作用不仅允许通过核反冲直接探测暗物质，还允许宇宙射线与之散射并将非相对论性暗物质提升到更高能量。如果暗物质与原子核的散射截面足够大，暗物质通量在穿过地球传播时会衰减，从而导致强烈的日调制。这种日调制为直接探测增强的亚GeV暗物质提供了另一个显著特征，这是除了具有更高反冲能量的信号之外的。
