Search for Light Dark Matter from the Atmosphere in PandaX-4T
Xuyang Ning, Abdusalam Abdukerim, Zihao Bo, Wei Chen, Xun Chen, Chen Cheng, Zhaokan Cheng, Xiangyi Cui, Yingjie Fan, Deqing Fang, Changbo Fu, Mengting Fu, Li‐Sheng Geng, Karl Giboni, Linhui Gu, Xuyuan Guo, Chencheng Han, K. Han, Changda He, Jinrong He, Di Huang, Yanlin Huang, J. Huang, Zhou Huang, Ruquan Hou, Yu Hou, Xiangdong Ji, Yonglin Ju, Chenxiang Li, Jiafu Li, Mingchuan Li, Shuaijie Li, Tao Li, Q. Lin, Jianglai Liu, Congcong Lu, Xiaoying Lu, Lingyin Luo, Yunyang Luo, Wenbo Ma, Y. G., Yajun Mao, Yue Meng, Ningchun Qi, Zhicheng Qian, Xiangxiang Ren, Nasir Shaheed, Xiaofeng Shang, Xiyuan Shao, Guofang Shen, Lin Si, Wenliang Sun, Andi Tan, Yi Tao, Anqing Wang, Meng Wang, Qiuhong Wang, Shaobo Wang, Siguang Wang, Wei Wang, Xiuli Wang, Zhou Wang, Yuehuan Wei, Mengmeng Wu, Weihao Wu, Jingkai Xia, M. Xiao, Xiang Xiao, Pengwei Xie, Binbin Yan, Xiyu Yan, Jijun Yang, Yong Yang, Yukun Yao, Chunxu Yu, Ying Yuan, Zhe Yuan, Xinning Zeng, Dan Zhang, Minzhen Zhang, Peng Zhang, Shibo Zhang, Shu Zhang, Tao Zhang, Wei Zhang, Yang Zhang, Yingxin Zhang, Yuanyuan Zhang, Li Zhao, Qibin Zheng, Jifang Zhou, N. Zhou, Xiaopeng Zhou, Yong Zhou, Yubo Zhou, Liangliang Su, Lei Wu
Abstract
We report a search for light dark matter produced through the cascading decay of $\ensuremath{\eta}$ mesons, which are created as a result of inelastic collisions between cosmic rays and Earth's atmosphere. We introduce a new and general framework, publicly accessible, designed to address boosted dark matter specifically, with which a full and dedicated simulation including both elastic and quasielastic processes of Earth attenuation effect on the dark matter particles arriving at the detector is performed. In the PandaX-4T commissioning data of $0.63\text{ }\text{ }\mathrm{tonne}\ifmmode\cdot\else\textperiodcentered\fi{}\mathrm{year}$ exposure, no significant excess over background is observed. The first constraints on the interaction between light dark matter generated in the atmosphere and nucleus through a light scalar mediator are obtained. The lowest excluded cross section is set at $5.9\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}37}\text{ }\text{ }{\mathrm{cm}}^{2}$ for a dark matter mass of $0.1\text{ }\text{ }\mathrm{MeV}/{c}^{2}$ and mediator mass of $300\text{ }\text{ }\mathrm{MeV}/{c}^{2}$. The lowest upper limit of $\ensuremath{\eta}$ to the dark matter decay branching ratio is $1.6\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}7}$.