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arXiv · 1708.06917

Dark Matter Results From 54-Ton-Day Exposure of PandaX-II Experiment

II Collaboration·Xiangyi Cui·Abdusalam Abdukerim·Wei Chen·Xun Chen·Yunhua Chen·Binbin Dong·Deqing Fang·Changbo Fu·Karl Giboni·Franco Giuliani·Linhui Gu·Yikun Gu·Xuyuan Guo·Zhifan Guo·Ke Han·Changda He·Di Huang·Shengming He·Xingtao Huang·Zhou Huang·Xiangdong Ji·Yonglin Ju·Shaoli Li·Yao Li·Heng Lin·Huaxuan Liu·Jianglai Liu·Yugang Ma·Yajun Mao·Kaixiang Ni·Jinhua Ning·Xiangxiang Ren·Fang Shi·Andi Tan·Cheng Wang·Hongwei Wang·Meng Wang·Qiuhong Wang·Siguang Wang·Xiuli Wang·Xuming Wang·Qinyu Wu·Shiyong Wu·Mengjiao Xiao·Pengwei Xie·Binbin Yan·Yong Yang·Jianfeng Yue·Dan Zhang·Hongguang Zhang·Tao Zhang·Tianqi Zhang·Li Zhao·Jifang Zhou·Ning Zhou·Xiaopeng Zhou
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Abstract

We report a new search of weakly interacting massive particles (WIMPs) using the combined low background data sets in 2016 and 2017 from the PandaX-II experiment in China. The latest data set contains a new exposure of 77.1 live day, with the background reduced to a level of 0.8$\times10^{-3}$ evt/kg/day, improved by a factor of 2.5 in comparison to the previous run in 2016. No excess events were found above the expected background. With a total exposure of 5.4$\times10^4$ kg day, the most stringent upper limit on spin-independent WIMP-nucleon cross section was set for a WIMP with mass larger than 100 GeV/c$^2$, with the lowest exclusion at 8.6$\times10^{-47}$ cm$^2$ at 40 GeV/c$^2$.

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II Collaboration, Xiangyi Cui, Abdusalam Abdukerim, Wei Chen, Xun Chen, Yunhua Chen, Binbin Dong, Deqing Fang, Changbo Fu, Karl Giboni, Franco Giuliani, Linhui Gu, Yikun Gu, Xuyuan Guo, Zhifan Guo, Ke Han, Changda He, Di Huang, Shengming He, Xingtao Huang, Zhou Huang, Xiangdong Ji, Yonglin Ju, Shaoli Li, Yao Li, Heng Lin, Huaxuan Liu, Jianglai Liu, Yugang Ma, Yajun Mao, Kaixiang Ni, Jinhua Ning, Xiangxiang Ren, Fang Shi, Andi Tan, Cheng Wang, Hongwei Wang, Meng Wang, Qiuhong Wang, Siguang Wang, Xiuli Wang, Xuming Wang, Qinyu Wu, Shiyong Wu, Mengjiao Xiao, Pengwei Xie, Binbin Yan, Yong Yang, Jianfeng Yue, Dan Zhang, Hongguang Zhang, Tao Zhang, Tianqi Zhang, Li Zhao, Jifang Zhou, Ning Zhou, Xiaopeng Zhou. 2017-08-23. Dark Matter Results From 54-Ton-Day Exposure of PandaX-II Experiment. https://doi.org/10.1103/physrevlett.119.181302

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