提高GdI3晶体中子探测效率的研究

项目名称： 提高GdI3晶体中子探测效率的研究

项目编号： No.11305247

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 数理科学和化学

项目作者： 黄跃峰

作者单位： 中国科学院上海应用物理研究所

项目金额： 30万元

中文摘要： 近年来，随着中子探测在核能利用、核物理研究和环境监测等领域应用的日益广泛，对中子探测器的研究越来越受到材料学和物理学者的重视。稀土元素钆（Gd）的热中子反应截面为十万量级，是其他常用核素如氦3、硼10、锂7 的20倍以上，是非常理想的中子探测、吸收材料。利用钆的这一特性进行中子探测研究，特别是基于Gd的中子闪烁体探测器越来越受到人们的广泛关注。GdI3:Ce晶体以中子响应截面大、光输出高、衰减时间短等优异的特性成为新型无机中子探测器中的佼佼者。但是，Gd与热中子的反应产物成份复杂，包括内转换电子、γ射线等，且γ射线的能量范围很宽，导致GdI3:Ce晶体离商业应用尚远。本项目创造性地依据内转换电子与本底γ射线在GdI3:Ce晶体内产生荧光的位置差异，通过解决这些次级粒子在晶体内荧光产生的机制、运输到高效收集所面临的关键科学问题，从而达到甄别γ射线，并有效提高热中子探测效率的研究目标。

中文关键词： 碘化钆；闪烁体；坩埚下降法；中子探测；探测效率

英文摘要： Duo to the widespread applications of neutron detection in the fields of nuclear power plant, nuclear physics research and environmental monitoring,etc,in recent years, research on the neutron detector receives more and more attention in material science and physics. Rare-earth element gadolinium (Gd) has very large cross-section to thermal neutrons (of the order of 100000 barn) which is more than 20 times greater than other usual converters,like 3He,10B and 7Li, makes it ideal to use for theromal neutron detection and absorbing material theoretically. Increasing attention has beening paid to the research of neutron detection by using the property of gadolinium, especially neutron scintillator detector based on Gd. With excellent properties such as large cross section,high light output,short decay time and so on,GdI3: Ce crystals becomes a leading candidate of new inorganic neutron detector. However,the reaction product ingredients between Gd and thermal neutron are very complicated, including internal conversion electron, γ-rays, etc., and the gamma ray energy range is very wide, resulting in GdI3: Ce crystals are still far away from commercial application. This research will innovatively foucs on the differences of location producing fluorescence in GdI3:Ce crystal between internal conversion electrons and the

英文关键词： GdI3；Scintillator；Bridgman technique；neutron detection；detection efficiency