基于三NaI(Tl)晶体探测器的放射源定位研究  

Radiation-source localization based on three NaI(Tl) crystal detectors

作　　者：周杨 赵越[1] 张振朝[1] 姚鑫森 左国平[1] ZHOU Yang;ZHAO Yue;ZHANG Zhenchao;YAO Xinsen;ZUO Guoping(School of Nuclear Science and Technology, University of South China, Hengyang 421001, China)

机构地区：[1]南华大学核科学技术学院

出　　处：《核技术》2019年第8期50-55,共6页Nuclear Techniques

基　　金：湖南省自然科学基金(No.2016JJ2106);南华大学研究生科学基金项目(No.2018KYY031)资助~~

摘　　要：设计了一种三NaI(Tl)晶体组成的γ射线源定位探测器系统,并通过模拟仿真及实验研究了三NaI(Tl)晶体探测器在137Cs辐射场中全能峰占比计数随距离及入射粒子方向变化的关系。结果表明:在远距离探测情况下,采用全能峰占比法可以有效消除源与探测器间距对角度分辨的影响。对于探测距离约为2.58m的1.36×10^6Bq的^137Cs源,测量的最大角度偏差≤1.72°,定位位置相对偏差为3.71%。[Background] With the wide application of radioactive sources and radioactive materials, the probability of losing radioactive source accidents is increasing.[Purpose] This study aims to locate lost radioactive sources by using three gamma ray directional detectors.[Methods] A gamma ray detection system consisting of three NaI(Tl) crystals was designed. The relationship between the full-energy peak ratio of the three NaI (Tl) detectors in the ^137Cs radiation field as a function of distance and incident particle direction was studied by simulation and experiment.[Results] The results show that in the case of long-range detection, the full-energy peak ratio method can effectively eliminate the influence of the source-detector spacing on the angular resolution. For the 1.36×10^6 Bq ^137Cs source at the distance of about 2.58 m, maximum angular deviation of measurement is 1.72° or less, and the relative positional deviation is 3.71%.[Conclusions] The designed three NaI(Tl) crystal detector has stable angular resolution in a certain range and can distinguish the incident direction of rays.

关 键 词：放射源定位 三NaI(Tl)晶体探测器 全能峰占比法 

分 类 号：TL99[核科学技术—核技术及应用]