A Monte Carlo study for the shielding of γ backgrounds induced by radionuclides for CDEX  

作　　者：李磊 岳骞 唐昌建 程建平 康克军 李荐民 李金 李玉兰 李元景 马豪 王子敬 薛涛 曾志 

机构地区：[1]Department of Applied Physics, Sichuan University [2]Department of Engineering Physics,Tsinghua University [3]Institute of Physics,Academia Sinica

出　　处：《Chinese Physics C》2011年第3期282-287,共6页中国物理C（英文版）

基　　金：Supported by National Natural Science Foundation of China (10935005,10945002)

摘　　要：The CDEX （China Dark matter EXperiment） Collaboration will carry out a direct search for WIMPs （Weakly Interacting Massive Particles） using an Ultra-Low Energy Threshold High Purity Germanium （ULE-HPGe） detector at the CJPL （China JinPing deep underground Laboratory）. A complex shielding system was designed to reduce backgrounds and a detailed GEANT4 Monte Carlo simulation was performed to study the achievable reduction of γ rays induced by radionuclides and neutron backgrounds by D（γ,n）p reaction. Furthermore, the upper level of allowed radiopurity of shielding materials was estimated under the constraint of the expected goal. Compared with the radiopurity reported by other low-background rare-event experiments, it indicates that the shielding used in the CDEX can be made out of materials with obtainable radiopurity.The CDEX （China Dark matter EXperiment） Collaboration will carry out a direct search for WIMPs （Weakly Interacting Massive Particles） using an Ultra-Low Energy Threshold High Purity Germanium （ULE-HPGe） detector at the CJPL （China JinPing deep underground Laboratory）. A complex shielding system was designed to reduce backgrounds and a detailed GEANT4 Monte Carlo simulation was performed to study the achievable reduction of γ rays induced by radionuclides and neutron backgrounds by D（γ,n）p reaction. Furthermore, the upper level of allowed radiopurity of shielding materials was estimated under the constraint of the expected goal. Compared with the radiopurity reported by other low-background rare-event experiments, it indicates that the shielding used in the CDEX can be made out of materials with obtainable radiopurity.

关 键 词：Monte Carlo simulation dark matter underground experiment radionuclides 

分 类 号：O572.21[理学—粒子物理与原子核物理]