Dual-sided Trench Shaped Neutron Detector Using 6LiF/α-Al2O3:C Based on Optically Stimulated Luminescence
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摘要: 中子个人剂量监测对核电厂、核动力装置、研究堆和高能加速器等核设施工作人员具有重要意义。光释光技术具有读出速度快和多次重复读取等优点,是中子个人剂量监测的重要发展方向。本文设计了一种双面沟槽型6LiF/α-Al2O3:C光释光中子探测器(DS-TSOSLND),采用蒙特卡罗程序Geant4计算分析了不同沟槽宽度、深度和沟槽比对探测器性能的影响规律,探索其中子探测机理。基于Geant4模拟计算结果,结合目前α-Al2O3:C晶体微结构加工工艺条件,成功制备了DS-TSOSLND。137Cs源和重水慢化252Cf中子源测试结果表明,新研制的DS-TSOSLND中子探测阈为10.3 μSv,0.05~20 mSv内其中子剂量响应呈线性关系,在中子个人剂量监测领域具有广阔的应用前景。Abstract: Personal neutron dosimetry is of great significance to the staff of nuclear facilities such as nuclear power plants, nuclear power units, research reactors and high-energy accelerators. Optically stimulated luminescence (OSL) technique has the advantages of fast reading speed and repeated reading many times, and is an important development direction of neutron personal dose monitoring. In this paper, a dual-sided trench shaped optically stimulated luminescence neutron detector (DS-TSOSLND) using 6LiF/α-Al2O3:C is designed, and the Monte Carlo code Geant4 is used to calculate and analyze the influences of different trench width, depth and trench ratio on the detector performance, so as to explore its neutron detection mechanism. Based on the simulation results of Geant4, DS-TSOSLND was successfully developed by combining the current processing conditions of α-Al2O3:C crystal microstructure. The test results of 137Cs source and heavy water moderated 252Cf neutron source show that the neutron detection threshold of the newly developed DS-TSOSLND is 10.3 μSv, and the neutron dose response is linear in the range of 0.05~20 mSv, which has broad application prospects in the field of personal neutron dosimetry.
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表 1 Geant4模拟计算参数
Table 1. Parameters for Geant4 Simulation
参数 数值 α-Al2O3:C衬底厚度/μm 500 H/μm 10~200 T/μm 10~50 沟槽比(T/Wcell) 0.1~0.9 中子能量/eV 0.025 -
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