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arXiv · 1305.0401

The CDEX-1 1 kg Point-Contact Germanium Detector for Low Mass Dark Matter Searches

Abstract

The CDEX Collaboration has been established for direct detection of light dark matter particles, using ultra-low energy threshold p-type point-contact germanium detectors, in China JinPing underground Laboratory (CJPL). The first 1 kg point-contact germanium detector with a sub-keV energy threshold has been tested in a passive shielding system located in CJPL. The outputs from both the point-contact p+ electrode and the outside n+ electrode make it possible to scan the lower energy range of less than 1 keV and at the same time to detect the higher energy range up to 3 MeV. The outputs from both p+ and n+ electrode may also provide a more powerful method for signal discrimination for dark matter experiment. Some key parameters, including energy resolution, dead time, decay times of internal X-rays, and system stability, have been tested and measured. The results show that the 1 kg point-contact germanium detector, together with its shielding system and electronics, can run smoothly with good performances. This detector system will be deployed for dark matter search experiments.

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Ke-Jun Kang, Qian Yue, Yu-Cheng Wu, Jian-Ping Cheng, Yuan-Jing Li, Yang Bai, Yong Bi, Jian-Ping Chang, Nan Chen, Ning Chen, Qing-Hao Chen, Yun-Hua Chen, You-Chun Chuang, Zhi Dend, Qiang Du, Hui Gong, Xi-Qing Hao, Qing-Ju He, Xin-Hui Hu, Han-Xiong Huang, Teng-Rui Huang, Hao Jiang, Hau-Bin Li, Jian-Min Li, Jin Li, Jun Li, Xia Li, Xin-Ying Li, Xue-Qian Li, Yu-Lan Li, Heng-Ye Liao, Fong-Kay Lin, Shin-Ted Lin, Shu-Kui Liu, Lan-Chun Lv, Hao Ma, Shao-Ji Mao, Jian-Qiang Qin, Jie Ren, Jing Ren, Xi-Chao Ruan, Man-Bin Shen, Lakhwinder Singh, Manoj Kumar Singh, Arun Kumar Soma, Jian Su, Chang-Jian Tang, Chao-Hsiung Tseng, Ji-Min Wang, Li Wang, Qing Wang, Tsz-King Henry Wong, Shi-Yong Wu, Wei 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, Zhi Zeng, Lan Zhang, Yun-Hua Zhang, Ming-Gang Zhao, Wei Zhao, Su-Ning Zhong, Zu-Ying Zhou, Jing-Jun Zhu, Wei-Bin Zhu, Xue-Zhou Zhu, Zhong-Hua Zhu. 2013-05-02. The CDEX-1 1 kg Point-Contact Germanium Detector for Low Mass Dark Matter Searches. https://doi.org/10.1088/1674-1137/37/12/126002

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