就地NaI谱仪对面源的刻度研究  

Study on Efficiency Calibration of in-situ NaI Spectrometer for Planar Sources

作　　者：严亦泽 宋卫杰[1] 陈凌[1] 李玥珺 YAN Yi-ze;SONG Wei-jie;CHEN Ling;LI Yue-jun(China Institute of Atomic Energy,Beijing 102413,China)

机构地区：[1]中国原子能科学研究院,北京102413

出　　处：《价值工程》2024年第14期112-114,共3页Value Engineering

摘　　要：核事故应急时,亟需快速确定放射性污染核素种类、污染程度和范围。由于核事故条件下地表沉降的放射性核素近似均匀面源分布,因此问题简化为快速、准确地获取均匀面源的活度浓度。对一台就地碘化钠谱仪建立了蒙特卡罗模型,得到距离地面1m处的谱仪对不同位置点源的探测效率,并通过积分的方式,计算得到谱仪对面源的探测效率。最后建立实验系统,通过实验验证就地碘化钠谱仪数值模拟模型的准确性以及刻度方法的合理性。结果表明,模拟与实验的探测效率偏差在12%以内,通过该刻度方法获得碘化钠谱仪的探测效率可靠。During nuclear emergencies,it is urgent to quickly determine the extent and scope of radioactive contamination.Due to the approximate planar distribution of radioactive nuclides under nuclear accident conditions,the problem is simplified to quickly and accurately obtain the activity concentration of a planar source.This article establishes a Monte Carlo model for an in-situ NaI spectrometer and obtains the efficiency of the spectrometer at 1 m from the ground for point sources at different positions.Efficiency of the spectrometer for planar sources is obtained through integration.The accuracy of the spectrometer model and the rationality of the calibration method were verified through experiments.The results show that the deviation between the detection efficiency of the simulation and the experiment is within 12%.The efficiency of the NaI spectrometer obtained by this calibrate method is reliable.

关 键 词：就地碘化钠谱仪 面源 探测效率 应急监测 蒙特卡罗模拟 

分 类 号：TL817[核科学技术—核技术及应用]