In recent years, monitoring of spent nuclear fuel inside dry cask storage has become an important area of national security. Muon tomography is a useful method for monitoring spent nuclear fuel because it uses high energy muons that penetrate deep into the target material and provides a 3-D structure of the inner materials.

We designed a muon tomography system consisting of four 2-D position sensitive detector and characterized and optimized the system parameters. Each detector, measuring 200 × 200 cm², consists of a plastic scintillator, wavelength shifting (WLS) fibers and, SiPMs. The reconstructed image is obtained by extracting the intersection of the incoming and outgoing muon tracks using a Point-of-Closest-Approach (PoCA) algorithm.

The Geant4 simulation was used to evaluate the performance of the muon tomography system and to optimize the design parameters including the pixel size of the muon detector, the field of view (FOV), and the distance between detectors. Based on the optimized design parameters, the spent fuel assemblies were modeled and the line profile was analyzed to conduct a feasibility study. Line profile analysis confirmed that muon tomography system can monitor nuclear spent fuel in dry storage container.

近年来，对干式储罐内乏核燃料的监测已成为国家安全的重要领域。介子断层扫描是监测乏核燃料的一种有用方法，因为它使用高能介子深入目标材料并提供内部材料的 3-D 结构。

我们设计了一个由四个二维位置敏感探测器组成的μ子层析成像系统，并对系统参数进行了表征和优化。每个检测器的尺寸为 200 × 200 cm ²，由塑料闪烁体、波长偏移 (WLS) 光纤和 SiPM 组成。重建图像是通过使用最近点 (PoCA) 算法提取传入和传出 μ 子轨道的交点来获得的。

Geant4 仿真用于评估 μ 子层析成像系统的性能并优化设计参数，包括 μ 子探测器的像素大小、视场 (FOV) 和探测器之间的距离。基于优化的设计参数，对乏燃料组件进行建模并分析线路剖面以进行可行性研究。线剖面分析证实，μ子层析成像系统可以监测干式储存容器中的核乏燃料。