航空γ能谱探测人工放射性核素检测限研究  

Study of the detection limit of manmade radionuclide detected by airborne gamma ray spectrometry

作　　者：倪卫冲[1] 蔡文军[1] 高国林[1] NI Weichong;CAI Wenjun;GAO Guolin(Airborne Survey and Remote Sensing Center of Nuclear Industry,China National Airborne Monitoring Technical Support Center for Nuclear Emergency,China National Airborne Monitoring Center for Nuclear Emergency,China National Airborne Radiation Monitoring Team Jbr Nuclear Emergency Rescue,CNNC Key Laboratory of Uranium Resource Geophysical Exploration Technology,Shijiazhuang 050002,China)

机构地区：[1]核工业航测遥感中心国家核应急航空监测技术支持中心国家核应急航空监测中心国家核应急救援航空辐射监测分队中核集团铀资源地球物理勘查技术中心(重点实验室),石家庄050002

出　　处：《核技术》2018年第10期20-25,共6页Nuclear Techniques

基　　金：国家自然科学基金面上项目(No.41474107);国家重点专项(No.2017YFC0602105)资助~~

摘　　要：核与辐射航空监测中人工放射性核素探测下限是衡量核与辐射航空监测能力的一个重要指标。基于大体积NaI(Tl)探测器核与辐射航空监测系统、固定翼飞机(Y-12和Y-5飞机)在全国数个不同辐射背景地区不同飞行高度的测量数据,研究航空γ能谱探测人工放射性核素137Cs和60Co探测下限的影响因素。结果表明:随航测高度和航测飞行速度的降低,人工放射性核素的探测下限相应地降低;在同一个航测高度上,探测下限随辐射背景水平而增大;水域上对人工放射性核素的探测下限最低;随人工放射性核素γ射线能量的降低,探测下限反而增大。本次研究为核与辐射航空监测中有效控制影响因素降低人工放射性核素探测下限提供了重要依据。[Background] The detection limit of manmade radionuclide in airborne monitoring is an important specification to measure detectable ability of airborne monitoring for nuclear and/or radiation. [Purpose] This study aims to find effect factors of detection limits of manmade radionuclide in airborne monitoring. [Methods] Based on the airborne monitoring data for the airborne monitoring system with NaI（Tl） detectors of the large volume（downward-looking for 50 341 cm3/upward-looking for 12 585 cm3）, Y-12 and Y-5 model wing-fixed aircraft, different altitude, and areas with the different radiation background levels, research diversification of detection limit of manmade radionuclide 137 Cs and 60 Co. [Results] Detection limits of manmade radionuclides decrease with the reducing of airborne altitude and flight speed. On the same airborne altitude, detection limits are corresponding to largen with the raise of radiation background level. Detection limits of manmade radionuclides are of the minimum on the waters. Detection limits are opposite to largen with the reducing of gamma-ray energy of manmade radionuclides. [Conclusion] Research provides important basis on how to control factors effectively and reduce detection limits of manmade radionuclides.

关 键 词：核与辐射航空监测 NAI(TL)探测器 航空γ能谱仪 137Cs 60Co 探测下限 

分 类 号：TL751[核科学技术—辐射防护及环境保护] TL817.2