"Physical Review Letters" published the latest scientific research progress of dark matter detection by PandaX experimental group with "Editor's recommendation"

Recently, Liu Jianglai, Zhou Ning, Cui Xiangyi, members of the PandaX cooperation group led by Shanghai Jiao Tong University, together with Li Zhengdao scholar Ge Shaofeng and Zijinshan Observatory researcher Yuan Qiang, published PandaX-II II in Physical Review Letters as an "Editor's Recommendation" paper.

Figure 1: The light dark matter (DM: dark matter) accelerated by cosmic rays (CR: cosmic ray) mainly comes from the direction of the center of the Milky Way, and the stellar diurnal periodic modulation characteristics caused by the Earth's rotation and shielding effect

The signal probe used in this study was proposed by theorists Ge Shaofeng, Yuan Qiang and experimental team members Zhou Ning and Liu Jianglai in another collaborative article: Light dark matter accelerated by cosmic rays from the Milky Way is caused by the Earth's rotation and shielding effect Characteristics of periodic modulation of sidereal days [PRL 126, 091804 (2021)]

Aiming at this new type of sidereal day modulation signal, the PandaX experimental team performed a detailed Monte Carlo simulation of the process of dark matter passing through rocks and entering the Jinping underground laboratory, fully including the effects of nuclear shape factor and angular deflection, and considering elasticity The scope of application of the scattering process, and finally a reliable earth shielding effect is obtained

Figure 2: Sidereal time distribution and deposition energy distribution of 25 events in the nuclear recoil signal region

Thanks to the low radioactive background and large exposure of the PandaX experiment, the experimental group gave strict restrictions on light dark matter

Figure 3: PandaX-II experimental data using sky-modulated new probes for tight confinement of low-mass dark matter

The first author of the experimental article is Cui Xiangyi, a postdoctoral fellow at the Li Zhengdao Institute.

Experimental article link: https://doi.

Link to theoretical article: https://doi.