固体反冲质子辐射转换体THGEM快中子探测器特性模拟研究

摘要

使用Geant4模拟研究了基于聚乙烯辐射转换材料的THGEM快中子探测器的辐射转换特性。结果表明，探测器响应具有一定阈特性，其灵敏度、响应阈值随辐射体厚度、吸收层厚度、中子入射角度、辐射体面积变化而改变。中子垂直入射，聚乙烯辐射体厚度50μm、铝吸收层厚度10μm时，探测器阈上响应具有较好的坪特性，阈值为2．2 MeV，灵敏度为1．0×10-4 cm2。%Response characteristic of the THGEM fast neutron detector based on HDPE recoil proton radiation material is simulated by Geant4 toolkit.Results show that the detector has a threshold response, the detection sensitivity and the threshold are related to the thickness of the radiator and of the absorber,the injection direc-tion of neutrons,and the radiator's areas.The response threshold to the neutrons from vertical direction is about 2.2 MeV and the detection sensitivity is 1.0 ×10 -4 cps˙cm2˙s while the radiator is 50 μm thick and the absorber is 10μm thick as the response curve presents a flat shape.