Abstract The detection of smuggled nuclear/radiological materials or weapons in commercial cargo remains a severe technical challenge due to the complexity of the global cargo network, sources of normally occurring radiation, and the broad nature of the threat. This article presents an analysis of the physical constraints on the nature and detectability of nuclear and radiological threats, using 122,500 radiography images from a containerized cargo stream. This analysis suggests that existing radiography systems, in conjunction with passive monitoring, may offer stronger detection capabilities than previously realized and presents data on the distribution of material in stream-of-commerce cargo to inform the development of future technologies.

中文翻译：

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商业货物中类似核/放射威胁的物体的频率和可探测性分析

摘要 由于全球货运网络的复杂性、正常发生的辐射源以及威胁的广泛性质，在商业货物中检测走私核/放射性材料或武器仍然是一项严峻的技术挑战。本文使用来自集装箱货物流的 122,500 幅射线照相图像，分析了对核威胁和放射性威胁的性质和可探测性的物理限制。该分析表明，现有的射线照相系统与被动监测相结合，可以提供比以前实现的更强的检测能力，并提供有关物流货物中材料分布的数据，为未来技术的发展提供信息。