移动式放射性气体监测仪能量响应的优化设计  

Optimization design for energy response of the mobile radioactive gas monitor

作　　者：周雪梅[1,2] 刘桂民[1,2] 陈永忠[1,2] 

机构地区：[1]中国科学院上海应用物理研究所嘉定园区,上海201800 [2]中国科学院钍基熔盐核能系统研究中心,上海201800

出　　处：《核技术》2018年第3期44-48,共5页Nuclear Techniques

基　　金：中国科学院战略性科技先导专项(No.XD02001003)资助~~

摘　　要：移动式放射性惰性气体监测仪对不同能量的γ射线存在不同的能量响应,为了提高其测量γ射线的准确性,需要对该监测仪进行能量响应补偿。利用MCNP(Monte Carlo N Particle Transport Code)软件模拟监测仪中的Na I(Tl)晶体在不同铅孔模型下的能量响应,通过比较不同模型下的标准偏差,选出屏蔽铅孔的最佳尺寸。模拟得出补偿铅孔的半径为3.0 cm、厚度为0.5 cm时,该监测仪的能量响应得到较好补偿。[Background] The mobile radioactive gas monitor responses differently to gamma rays at different energies. [Purpose] This study aims to accurately measure the dose of gamma radiation monitor by means of compensation for energy response. [Methods] Energy responses of Na I（Tl） crystals in the monitor in different lead-hole models were simulated using Monte Carlo N Particle Transport Code（MCNP） software. Various sizes of shielding lead hole were selected to compare the standard deviations of different models, and the optimum size of shielding lead hole was obtained. [Results ＆ Conclusion] The simulation result shows that the energy response of monitor is best compensated when the radius of hole is 3.0 cm and thickness of shielding lead is 0.5 cm.

关 键 词：移动式放射性气体监测仪 MCNP 能量响应补偿 铅屏蔽 

分 类 号：TL812.1[核科学技术—核技术及应用]