【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2.58 m的1.36×106Bq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%。更多还原

【Abstract】 [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 the137 Cs 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 1.36×106 Bq137 Cs 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.更多还原