Study on cosmogenic activation in germanium detectors for future tonne-scale CDEX experiment  

作　　者：JingLu Ma Qian Yue ShinTed Lin Henry Tsz-King Wong JinWei Hu LiPing Jia Hao Jiang Jin Li ShuKui Liu ZhongZhi Liu Hao Ma WeiYou Tang Yang Tian Li Wang Qing Wang Yi Wang LiTao Yang Zhi Zeng 

机构地区：[1]Key Laboratory of Particle and Radiation Imaging (Ministry of Education) and Department of Engineering Physics, Tsinghua University [2]Department of Physics, Tsinghua University [3]College of Physical Science and Technology, Sichuan University [4]Institute of Physics,Academia Sinica [5]Department of Physics, Beijing Normal University [6]Center for High Energy Physics, Tsinghua University [7]Collaborative Innovation Center of Quantum Matter

出　　处：《Science China(Physics,Mechanics & Astronomy)》2019年第1期32-41,共10页中国科学：物理学、力学、天文学（英文版）

基　　金：supported by the National Key Research and Development Program of China(Grant Nos.2017YFA0402200,and 2017YFA0402201);the National Science Fund for Distinguished Young Scholars(Grant No.11725522);the National Natural Science Foundation of China(Grant Nos.11475092,11475099,and 11675088);the National Basic Research Program of China(Grant No.2010CB833006);the Tsinghua University Initiative Scientific Research Program(Grant No.20151080354)

摘　　要：A study on cosmogenic activation in germanium was carried out to evaluate the cosmogenic background level of natural and ^(70)Ge depleted germanium detectors. The production rates of long-lived radionuclides were calculated with Geant4 and CRY.Results were validated by comparing the simulated and experimental spectra of CDEX-1B detector. Based on the validated codes, the cosmogenic background level was predicted for further tonne-scale CDEX experiment. The suppression of cosmogenic background level could be achieved by underground germanium crystal growth and high-purity germanium detector fabrication to reach the sensitivity requirement for direct detection of dark matter. With the low cosmogenic background, new physics channels,such as solar neutrino research and neutrinoless double-beta decay experiments, were opened and the corresponding simulations and evaluations were carried out.A study on cosmogenic activation in germanium was carried out to evaluate the cosmogenic background level of natural and ^(70)Ge depleted germanium detectors. The production rates of long-lived radionuclides were calculated with Geant4 and CRY.Results were validated by comparing the simulated and experimental spectra of CDEX-1B detector. Based on the validated codes, the cosmogenic background level was predicted for further tonne-scale CDEX experiment. The suppression of cosmogenic background level could be achieved by underground germanium crystal growth and high-purity germanium detector fabrication to reach the sensitivity requirement for direct detection of dark matter. With the low cosmogenic background, new physics channels,such as solar neutrino research and neutrinoless double-beta decay experiments, were opened and the corresponding simulations and evaluations were carried out.

关 键 词：COSMOGENIC ACTIVATION production rate GERMANIUM detectors BACKGROUND level DARK MATTER 

分 类 号：N[自然科学总论]