塑料闪烁体探测器中子/伽马甄别能力研究  

Study on Neutron/gamma Discrimination of Plastic Scintillator Detector

作　　者：秦茜 李玮[1] 焦听雨 李晓博 肖凯歌 李世垚 刘毅娜[1] 王志强[1] 刘蕴韬[1] QIN Xi;LI Wei;JIAO Ting-yu;LI Xiao-bo;XIAO Kai-ge;LI Shi-yao;LIU Yi-na;WANG Zhi-qiang;LIU Yun-tao(National Key Laboratory for Metrology and Calibration Techniques,China Institute of Atomic Energy,Beijing 102413,China)

机构地区：[1]中国原子能科学研究院计量与校准技术重点实验室,北京102413

出　　处：《宇航计测技术》2021年第3期91-96,共6页Journal of Astronautic Metrology and Measurement

摘　　要：利用塑料闪烁体探测器开展了两种中子/伽马(n/γ)甄别方法研究。塑料闪烁体的尺寸为直径2英寸、长2英寸。以241Am-Be源作为中子伽马混合源,分别用线性延迟法和长短积分时间窗的方法对塑料闪烁体探测器进行n/γ甄别性能研究。利用PSD(脉冲形状甄别)图及计算得出的FOM(品质因子),比较了这两种方法的n/γ甄别效果。结果表明:线性延迟法的甄别效果较差,长短积分时间窗的方法甄别效果较好,当积分时间窗的长门为400ns,短门为60ns时,塑料闪烁体探测器EJ276的n/γ甄别效果最好且n/γ甄别的误判率最低。Research of two discrimination methods on neutron and gamma ray has been carried out using a plastic scintillator detector EJ276 with 2 inches in diameter and 2 inches in length.In the mixed radiation field of neutron and gamma,which is generated by ^(241)Am-Be,neutron/gamma discrimination performance of the plastic scintillator detector was studied by the linear delay method and the long and short integral time window method,respectively.The neutron/gamma discrimination effect between these two methods was compared via PSD(Pulse Shape Discrimination)diagram and FOM(Figure of Merit).The result shows that the method of charge comparison on neutron/gamma discrimination is better than the method of linear delay.And when it's of 400 ns long gate and 60 ns short gate in the charge comparison,EJ276 has the best discrimination on neutron/gamma with lowest misjudgment ratio.

关 键 词：n/γ甄别 脉冲形状甄别 塑料闪烁体探测器 线性延迟法 长短积分时间窗法 品质因子 

分 类 号：O571.53[理学—粒子物理与原子核物理]