“裂变-电子收集”中子探测技术研究

项目名称： “裂变-电子收集”中子探测技术研究

项目编号： No.11205141

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 物理学II

项目作者： 王栋

作者单位： 中国工程物理研究院核物理与化学研究所

项目金额： 28万元

中文摘要： 裂变法是中子测量的常用方法之一，主要是通过探测离开靶物质表面的裂变碎片来获得测量信号，本课题拟对一种新型的中子探测技术进行研究，这里称之为"裂变-电子收集"技术，与传统技术的不同之处在于，该技术通过收集裂变碎片在裂变材料内产生的次级电子获取信号。通过优化结构材料和布局设计，可使采用该技术的探测系统具备体积小、能量响应平坦、时间响应快、n/γ甄别能力强和动态范围大的优点。课题研究采用蒙卡模拟的方法，编制基于Geant4工具包的模拟软件，完整模拟从中子入射到电子收集的探测过程，减少物理建模中的简化和假设，掌握探测器参数与性能之间的规律关系，随后进行探测系统的物理设计和机械设计，试制探测器并针对探测器性能进行实验研究，对设计方案进行验证和完善，获取最佳的性能参数。基于该技术的探测系统可应用于多种高通量辐射场中子测量，具有广泛的应用前景。

中文关键词： “裂变-电子收集”；中子测量；能量响应；时间响应；灵敏度

英文摘要： Fission method is one of neutron measuring methods in common use, and usually it gets signals from fission fragments which leave from target material. The subject want to make a research on a novel neutron measuring technique, here we call it "fission electron-collection" technique. The difference from traditional techniques is that the new technique gets signals from the secondary electrons produced by the fission fragments in the fission material. Through optimizing the structure design and material choice, the detection system which employ this new technique have characteristics of little volume, flat energy response, fast time response, strong n/γ discrimination and wide dynamic range. Through developing simulation software based on Geant4 Monte Carlo toolkits, the research can make a simulation of full process from neutron incidence to electron collection, the simplifications and hypotheses can be reduced in physical model building. After mastering of the rules between the detector parameters and performance, the physical and mechanical design can be implemented, and the design scheme can be examined and optimized through the neutron and gamma irradiation experiment, then get the best parameters. The detection system based on this technique could be used in neutron measurement of many high flux radiation fi

英文关键词： “fission electron-collection”；neutron measurement；energy response；time response；sensitivity