蒙特卡罗方法调整探测器死层厚度和冷指尺寸的研究  

Research on the Adjustment of Detector's Dead- layer Thickness and Cold finger Size with Monte Carlo Simulation.

作　　者：徐翠华[1] 王思广[2] 周强[1] 张庆[1] 任天山[1] 耿秀生[1] 

机构地区：[1]中国疾病预防控制中心辐射防护与核安全医学所,北京100088 [2]中国原子能科学研究院,北京102413

出　　处：《中国辐射卫生》2003年第4期203-204,共2页Chinese Journal of Radiological Health

基　　金：国防科技预研项目(56.1.4)

摘　　要：目的 用蒙特卡罗(MC)方法计算效率和实测效率的比较,调整HPGe探测器死层厚度和冷指尺寸,提高MC方法计算HPGe探测器γ射线探测效率的准确度。方法 在理论分析探测器死层厚度和冷指尺寸对γ射线探测效率影响的基础上,用^(137)Cs刻度源在不同距离处实际测量HPGe探测器的效率,并将探测器死层厚度和冷指尺寸调节前、后计算效率与实测效率进行比较。结果 探测器死层厚度和冷指尺寸调节前与调节后相比,理论计算与实测效率相对偏差的平均值由5.301％提高到3.937％。结论 相对偏差的明显改善,不仅增强了MC软件的模拟计算功能,也提高了放射性测量结果的准确度。Objective For improving the accuracy in radioactive measurement, to adjust HPGe detector's dead - layer thickness and cold -finger size in Monte Carlo simulation calculation through comparing the efficiencies calculated with the measured. Methods The adjusting method is described first, and then, the calculated results befofe and after adjusted are compared with measured efficiencies, which is made by putting a137 Cs standard source at different distances from the detector. Results It is proved that the average relative differences calculated and actual- measured before and after being adjusted have been increased from 5.301% to 3.937% .Conclusion Both the calculating function of MC simulation program and the accuracy of radioactive measurements have been surely improved.

关 键 词：蒙特卡罗方法 死层厚度 冷指尺寸 高纯锗探测器 Γ射线 

分 类 号：TH774[机械工程—仪器科学与技术]