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arXiv · 1402.4591

Study of the material photon and electron background and the liquid argon detector veto efficiency of the CDEX-10 experiment

Abstract

The China Dark Matter Experiment (CDEX) is located at the China Jinping underground laboratory (CJPL) and aims to directly detect the WIMP flux with high sensitivity in the low mass region. Here we present a study of the predicted photon and electron backgrounds including the background contribution of the structure materials of the germanium detector, the passive shielding materials, and the intrinsic radioactivity of the liquid argon that serves as an anti-Compton active shielding detector. A detailed geometry is modeled and the background contribution has been simulated based on the measured radioactivities of all possible components within the GEANT4 program. Then the photon and electron background level in the energy region of interest (<10^-2 events kg-1 day-1 keV-1 (cpkkd)) is predicted based on Monte Carlo simulations. The simulated result is consistent with the design goal of CDEX-10 experiment, 0.1 cpkkd, which shows that the active and passive shield design of CDEX-10 is effective and feasible.

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Jian Su, Zhi Zeng, Hao MA, Qian Yue, Jian-Ping Cheng, Jian-Ping Chang, Nan Chen, Ning Chen, Qing-Hao Chen, Yun-Hua Chen, Yo-Chun Chuang, Zhi Deng, Qiang Du, Hui Gong, Xi-Qing Hao, Qing-Ju He, Han-Xiong Huang, Teng-Rui Huang, Hao Jiang, Ke-Jun Kang, Hau-Bin Li, Jian-Min Li, Jin Li, Jun Li, Xia Li, Xin-Ying Li, Xue-Qian Li, Yu-Lan Li, Yuan-Jing Li, Heng-Yi Liao, Fong-Kay Lin, Shin-Ted Lin, Shu-Kui Liu, Lan-Chun Lü, Shao-Ji Mao, Jian-Qiang Qin, Jie Ren, Jing Ren, Xi-Chao Ruan, Man-Bin Shen, Lakhwinder Singh, Manoj Kumar Singh, Arun Kumar Soma, Chang-Jian Tang, Chao-Hsiung Tseng, Ji-Min Wang, Li Wang, Qing Wang, Henry Tsz-King Wong, Shi-Yong Wu, Yu-Cheng Wu, Hao-Yang Xing, Yin Xu, Tao Xue, Li-Tao Yang, Song-Wei Yang, Nan Yi, Chun-Xu Yu, Hao Yu, Xun-Zhen Yu, Xiong-Hui Zeng, Lan Zhang, Yun-Hua Zhang, Ming-Gang Zhao, Wei Zhao, Zu-Ying Zhou, Jing-Jun Zhu, Wei-Bin Zhu, Xue-Zhou Zhu, Zhong-Hua Zhu. 2014-02-19. Study of the material photon and electron background and the liquid argon detector veto efficiency of the CDEX-10 experiment. https://doi.org/10.1088/1674-1137/39/3/036001

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