基于CLYC闪烁体的中子能谱测量及反演方法

空间中子是影响航天器和航天员安全的重要辐射要素之一。优化中子探测器，提高测量效率，提升反演精度是中子测量的难点。中国空间站将搭载一种基于新型中子探测材料Cs2LiYCl6:Ce（CLYC）闪烁体的中子探测器，该探测器具有同时测量热中子和快中子，以及探测效率高等特点。针对该新型探测器的中子能谱反演，分析了不同能量中子在该探测器中的响应特点，分析了中子反演常用的概率迭代法和非负最小二乘（NNLS）法的优缺点，考虑到这2种方法在CLYC探测器反演应用中的不足，提出了基于增广矩阵的非负最小二乘（AM-NNLS）法。数值实验结果表明:AM-NNLS法具有反演运算效率高和反演相对误差小的特点，验证了所提方法的有效性。 

Neutron measurement and inversion based on CLYC scintillator

Neutron is one of the important radiation factors that affect the safety of spacecraft and astronauts. It is difficult for neutron measurement to optimize the neutron detector, improve the measurement efficiency, and improve the inversion accuracy. A neutron detector based on a new type of neutron detection material Cs2LiYCl6:Ce (CLYC) scintillator will be installed on the space station in China. This detector has the characteristics of measuring thermal neutrons and fast neutrons simultaneously, and has high detection efficiency, etc. For the neutron spectrum inversion of this detector, the response characteristics of different energy neutrons in the detetor are analyzed, and the advantages and disadvantages of the probabilistic iterative method and Non-Negative Least Square (NNLS) method commonly used in neutron spectrum inversion are analyzed, considering the disadvantages of these two methods in the inversion application of CLYC detector, a Non-Negative Least Square method based on the Augmented Matrix (AM-NNLS) is proposed. The numerical experiment results show that the AM-NNLS method has the characteristics of high inversion operation efficiency and small inversion relative error, which verifies the effectiveness of the method.