摘要
In recent years,gas electron multiplier(GEM)neutron detectors have been developing towards high spatial resolution and high dynamic counting range.We propose a novel concept of an Al stopping layer to enable the detector to achieve sub-millimeter(sub-mm)spatial resolution.The neutron conversion layer is coated with the Al stopping layer to limit the emission angle of ions into the drift region.The short track projection of ions is obtained on the signal readout board,and the detector would get good spatial resolution.The spatial resolutions of the GEM neutron detector with the Al stopping layer are simulated and optimized based on Geant4 Garfield Interface.The spatial resolution of the detector is 0.76 mm and the thermal neutron detection efficiency is about 0.01%when the Al stopping layer is 3.0μm thick,the drift region is 2 mm thick,the strip pitch is 600μm,and the digital readout is employed.Thus,the GEM neutron detector with a simple detector structure and a fast readout mode is developed to obtain a high spatial resolution and high dynamic counting range.It could be used for the direct measurement of a high-flux neutron beam,such as Bragg transmission imaging,very small-angle scattering neutron detection and neutron beam diagnostic.
作者
周建晋
周健荣
周晓娟
朱林
杨建清
杨桂安
张毅
丁宝卫
胡碧涛
孙志嘉
段利敏
陈元柏
Jianjin Zhou;Jianrong Zhou;Xiaojuan Zhou;Lin Zhu;Jianqing Yang;Guian Yang;Yi Zhang;Baowei Ding;Bitao Hu;Zhijia Sun;Limin Duan;Yuanbo Chen(School of Nuclear Science and Technology,Lanzhou University,Lanzhou 730000,China;Spallation Neutron Source Science Center,Dongguan 523803,China;State Key Laboratory of Particle Detection and Electronics,Institute of High Energy Physics,Chinese Academy of Sciences,Beijing 100049,China;University of Chinese Academy of Sciences,Beijing 100049,China;Institute of Modern Physics,Chinese Academy of Sciences,Lanzhou 730000,China)
基金
supported by the National Key R&D Program of China(Grant No.2017YFA0403702)
the National Natural Science Foundation of China(Grant Nos.11574123,11775243,12175254,and U2032166)
Youth Innovation Promotion Association CAS and Guangdong Basic and Applied Basic Research Foundation(Grant No.2019A1515110217)
the Xie Jialin Foundation,China(Grant No.E1546FU2)。