^(252)Cf裂变中子源实时测量瞬发中子的衰减常数  

Real-time measurement of the prompt neutron decay constant based on ^(252)Cf source

作　　者：米德伶[1] 唐跃林[1] 魏彪[1] 任勇[2] 冯鹏[1] 金晶[1] 

机构地区：[1]重庆大学光电技术及系统教育部重点实验室,重庆400044 [2]重庆大学通信工程学院,重庆400044

出　　处：《重庆大学学报（自然科学版）》2010年第12期84-87,共4页Journal of Chongqing University

基　　金：重庆市科委攻关项目(CSTC2009AC3048);中央高校基本科研业务费联合资助(CDJZR11120006)

摘　　要：瞬发中子衰减常数是衡量中子链式反应一个不可或缺的参量。针对核裂变系统对瞬发中子衰减常数测量的实时性要求,研究了一种基于252Cf裂变中子源、利用PC平台中子脉冲序列高速实时频谱分析系统的实时瞬发中子衰减常数测量方法。该方法以252Cf源信号作为随机脉冲源和起始信号,利用其中一路探测器通道在高达1GHz采样率下采集获得中子脉冲序列并按多道时间分析器的原理实时进行多道数据转换,得到核裂变系统的瞬发中子衰减图谱,再进行指数的最小二乘曲线拟合得到瞬发中子衰减常数。实验结果表明,利用系统测得的瞬发中子衰减图谱进行单指数最小二乘曲线拟合,获得了瞬发中子衰减常数为1.033μs-1,这为实时测量核裂变系统的瞬发中子衰减常数提供了一种新的途径。Prompt neutron decay constant is a key parameter in neutron action. Due to the real-time measurement demand for prompt neutron decay constant,a measurement method for prompt neutron decay constant is developed based on 252Cf Source and neutron pulse frequency spectrum measurement system. Triggered and initiated by 252Cf random neutron source,the pulse from detector is acquired and real-time converted to multi-channel data up to 1 GHz sample rate. The prompt decay constant can be acquired by utilize least squares of single exponential fitting to prompt decay curve based on prompt decay spectrum. The experimental result shows that prompt decay constant is 1.033μs-1 and the proposed method is a novel method for real-time measurement of prompt neutron decay constant.

关 键 词：252Cf 中子脉冲频谱分析 中子链式反应 瞬发中子衰减常数 实时测量 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]