Measurement of intrinsic radioactive backgrounds from the ^(137)Cs and U/Th chains in CsI(Tl) crystals  

作　　者：刘书魁 岳骞 林兴德 李元景 唐昌建 王子敬 幸浩洋 杨朝文 赵伟 朱敬军 

机构地区：[1]College of Physical Science and Technology, Sichuan University [2]Key Laboratory of Particle and Radiation Imaging (Ministry of Education) and Department of Engineering Physics, Tsinghua University [3]Institute of Physics, Academia Sinica

出　　处：《Chinese Physics C》2015年第4期55-62,共8页中国物理C（英文版）

基　　金：Supported by National Natural Science Foundation of China(11275107,11175099)

摘　　要：The inorganic CsI（Tl） crystal scintillator is a candidate anti-compton detector for the China Dark matter Experiment. Studying the intrinsic radiopurity of the CsI（Tl） crystal is an issue of major importance. The timing, energy and spatial correlations, as well as the capability of pulse shape discrimination provide powerful methods for the measurement of intrinsic radiopurities. The experimental design, detector performance and event-selection algorithms are described. A total of 359×3 kg-days data from three prototypes of CsI（Tl） crystals were taken at China Jinping Underground Laboratory （CJPL）, which offers a good shielding environment. The contamination levels of internal isotopes from 137Cs, 232Th and 238U series, as well as the upper bounds of 235U series are reported. Identification of the whole α peaks from U/Th decay chains and derivation of those corresponding quenching factors are achieved.The inorganic CsI（Tl） crystal scintillator is a candidate anti-compton detector for the China Dark matter Experiment. Studying the intrinsic radiopurity of the CsI（Tl） crystal is an issue of major importance. The timing, energy and spatial correlations, as well as the capability of pulse shape discrimination provide powerful methods for the measurement of intrinsic radiopurities. The experimental design, detector performance and event-selection algorithms are described. A total of 359×3 kg-days data from three prototypes of CsI（Tl） crystals were taken at China Jinping Underground Laboratory （CJPL）, which offers a good shielding environment. The contamination levels of internal isotopes from 137Cs, 232Th and 238U series, as well as the upper bounds of 235U series are reported. Identification of the whole α peaks from U/Th decay chains and derivation of those corresponding quenching factors are achieved.

关 键 词：scintillation detector CsI（T1） crystal intrinsic radiopurity alpha 

分 类 号：O73[理学—晶体学]