基于天然μ子散射特征评估铀板内水平狭缝宽度的方法

摘要

Background:Muon tomography based on multiple Coulomb scattering (MCS) has been widely used in structural detection of nuclear objects. However, for some particular objects, the tomographic method would be thwarted by failing to imaging them.Purpose:In view of the technical difficulties in structural detection of those objects, a novel method named "Forward Comparison Method (FCM)" was proposed.Methods:Both the deformation and its scale were identified effectively by directly evaluating the evolution of muon scattering properties with respect to the object. This method, instead of the traditional inverse one, showed a methodological superiority in detection of nuclear objects with prior knowledge of the original structure.Results:Preliminary results based on a computational simulation demonstrated that FCM could be used to identify the horizontal slit in a uranium slab and evaluate its width on the magnitude of sub-millimeters, on condition that the muon flux was reasonable.Conclusion:The FCM method can be effectively applied in structural detection of particular nuclear objects of hollow structure on a satisfactory timescale.%针对经典 μ 子成像方法用于特殊对象结构探测的技术难点,提出了一种通过直接比较对象发生结构变化前后 μ 子散射特征的差异来进行形变类型和尺度判定的新思路,称为正向参比法.相比于经典的逆向反演法,该方法在原理上对于初始结构已知的特殊核对象的结构变化探测更有优势.从初步模拟结果来看,在合理的天然μ子通量下,该方法可实现铀板内亚毫米尺度水平狭缝的存在及其尺度的准确判定.