涂硼正比计数管慢化体对中子探测效率影响研究  

Study on the effect of moderator of the proportional Boron-lined counter on the neutron detection efficiency

作　　者：陈学勇[1] 廖燕飞[1] 祝庆军[1,2] 宋逢泉[1,2] 宋钢[1,2] FDS团队 

机构地区：[1]中国科学院核能安全技术研究所,安徽合肥230031 [2]中国科学技术大学,安徽合肥230026

出　　处：《核科学与工程》2013年第1期55-59,共5页Nuclear Science and Engineering

基　　金：国家自然科学基金重大研究计划项目(91026004);中国科学院战略性先导科技专项(XDA03040000)

摘　　要：涂硼正比计数管是一种常用的反应堆源量程探测器,对热中子测量有很高的探测效率,对于快中子反应堆则需要增加合适的慢化体,提高中子探测效率。本文利用蒙特卡罗程序MCNP,模拟计算涂硼正比计数管在不同慢化体厚度的情况下,对各能量单能中子的相对探测效率和绝对探测效率,得到在不同慢化体厚度下,计数管的相对探测效率和绝对探测效率与中子能量的关系。最后针对快中子反应堆的典型中子能谱,模拟计算涂硼正比计数管在不同的慢化体设计时的探测效率,得出了一种优化的慢化体设计方案,对快中子反应堆核测量系统设计具有一定指导意义。The proportional boron-lined counter as a common source-range detector is widely used in reactor monitoring, which has high detection efficiency for thermal neutron. The detection efficiency of the proportional boron-lined counter for fast reactor monitoring can be improved by using proper moderator. The relative detection efficiency and absolute detection efficiency of the proportional boron-lined counter in different thickness of the moderator for mono-energy neutrons of different energy were simulated by using MCNP, the tend-line of the relative detection efficiency andabsolute detection efficiency were obtained. Also the detection efficiency of selected proportional boron-lined counter to the typical neutron spectrum of the fast reactor was simulated, and then the optimized moderator was designed. It would have some degree of guiding significance to design the nuclear measurement system of the fast reactor.

关 键 词：中子 涂硼正比计数管 探测效率 慢化体 

分 类 号：TL81[核科学技术—核技术及应用]