多毛细管中子聚焦透镜仿真模拟及实验研究  

Theoretical simulation and experimental study of the polycapillary neutron focusing lens

作　　者：崔靖朵 刘志国[1,2,3] 温今甫 潘秋丽 CUI Jingduo;LIU Zhiguo;WEN Jinfu;PAN Qiuli(Key Laboratory of Beam Technology of the Ministry of Education,College of Nuclear Science and Technology,Beijing Normal University,Beijing,China;Applied Optics Beijing Area Laboratory,Department of Physics,Beijing Normal University,Beijing,China;Institute of Radiation Technology,Beijing Academy of Science and Technology,Beijing,China)

机构地区：[1]北京师范大学核科学与技术学院射线束技术教育部重点实验室,北京 [2]北京师范大学物理学系应用光学北京市重点实验室,北京 [3]北京市科学技术研究院辐射技术研究所,北京

出　　处：《北京师范大学学报（自然科学版）》2024年第2期176-182,共7页Journal of Beijing Normal University(Natural Science)

基　　金：国家自然科学基金资助项目(210110027)。

摘　　要：为了分析中子波长,透镜几何参数对透镜聚焦性能的影响,利用MATLAB进行仿真建模和编程,根据射线追迹法模拟中子束在透镜中的传输;利用中国散裂中子源提供的0.10~1.18 nm波段多色中子束测试透镜聚焦性能.结果表明,透镜对所测宽波段中子束调控所得焦斑的模拟值562.0μm和实测值549.0μm非常接近,验证了仿真模型和程序的正确性.对实测焦斑数据进行分析得出:该透镜适用于0.20~1.18 nm波段;在适用波段内,焦斑尺寸与波长呈正相关,增益整体呈现先增大后降低的趋势.对通道内径变量系列仿真发现,在保证内外径比为0.8的前提下,降低微通道内径有利于获得具有高倍增益的小焦斑.To analyze the influence of neutron wavelengths and lens geometric parameters on the focusing performance of a polycapillary neutron focusing lens,the simulation model of the lens was established and the neutron beam transmission in the lens was simulated by the ray tracing method using MATLAB software.Moreover,the focusing performance of the lens was tested by using a polychromatic neutron beam in the wavelength range of 0.10~1.18 nm at China Spallation Neutron Source.The simulated focal spot size of 562.0μm and the measured value of 549.0μm are very consistent,which verifies the correctness of the simulation model and program.According to the data analysis of the measured focal spot,the applicable range of the lens is 0.20~1.18 nm.In this range,the focal spot size is positively correlated with the neutron wavelength,and the gain increases first and then decreases.In addition,the relationship between the focusing performance of the lens and the channel diameter was simulated.The results show that reducing the inner diameter of the microchannels is beneficial to obtain small focal spots with high gain when the inner diameter to outer diameter ratio is 0.8.

关 键 词：反射与折射 中子聚焦器件 聚焦性能 中子波长 微通道内径 

分 类 号：O435.1[机械工程—光学工程]