作者：林业¹, 方方¹, 陈伟¹, 何剑锋², 张君宝¹, 任家富¹

作者单位：1. 成都理工大学核技术与自动化工程学院, 四川 成都 610059;
2. 东华理工大学软件学院, 江西 南昌 330013

关键词：塑料闪烁体;能量窗口算法;天然放射性材料;人工放射源

摘要：

基于塑料闪烁体与射线的特殊作用,该文开展能量窗口法用于塑料闪烁体人工核素鉴别技术的研究。首先搭建基于塑料闪烁体的快速鉴别测量系统,使用人工放射性核素137Cs,60Co,241Am和天然放射性核素232Th 4种标准源对系统能量窗口进行刻度和计数分布实验,研究塑料闪烁体与射线作用时的脉冲分布和鉴别算法。在实验的基础上,使用总计数算法和能量窗口软件算法设计探测系统。测试结果表明:采用该算法的测量系统可以快速准确地从本底和天然放射性核素中鉴别出人工放射源。

γ radioactive man-made isotopes verification based on plastic scintillator

LIN Ye¹, FANG Fang¹, CHEN Wei¹, HE Jianfeng², ZHANG Junbao¹, REN Jiafu¹

1. College of Nuclear Technology & Automation Engineering, Chengdu University of Technology, Chengdu 610059, China;
2. College of Software Engineering, East China University of Technology, Nanchang 330013, China

Abstract: Plastic scintillators are mostly used as gammacounters because of their poor energy resolution. However, an energy windowing(EW) algorithm can perform rough nuclide identification with the spectral occupied from it.This paper has described the setup of a plastic scintillator-based measurement system to verify γ radioactive man-made isotopes using the EW algorithm. Discriminators are calibrated with standard sources ¹³⁷Cs, ⁶⁰Co,²⁴¹Am and naturalradioactive nuclides ²³²Th. Experiments are conducted to study the scale and count rate distribution of the EW window. After that,the count rate algorithm and the EW algorithm software are designed and used in PC. The results show that this system can quickly and accurately distinguish man-made radiation sources from background and naturally occurring radioactive materials.

Keywords: plastic scintillator;energy windowing algorithm;natural radioactive materials;man-made radiation source

2016, 42(4): 70-74  收稿日期: 2015-10-25;收到修改稿日期: 2015-11-22

基金项目: 国家自然科学基金项目(11365001)

作者简介: 林业(1988-),男,博士研究生,研究方向为核测控技术。

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