ABSTRACT This article examines challenges in international nuclear safeguards pertaining to the timely detection of highly enriched uranium production at large-scale gas centrifuge enrichment plants. To establish where present gas centrifuge enrichment plant safeguards measures and approaches could be strengthened, we have created a discrete time model for simulating hypothetical misuse scenarios, both through transient phases and at steady-state. We find that timely detection of misuse at modern large-scale facilities presents a challenge for international safeguards. A toolbox of unattended measurement systems, along with remote monitoring, however, could be used to improve detection timeliness, enabling the initiation of follow-up activities, potentially on a rapid time scale. These measures, which would need very low false alarm rates, should be implemented in a graded approach, depending on the characteristics of each enrichment plant and an analysis of plausible acquisition paths for the State in which it is situated. Some of these technologies could provide significant benefit to plant operators.

中文翻译：

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大型气体离心浓缩厂的及时验证

摘要 本文探讨了与及时检测大型气体离心浓缩厂的高浓缩铀生产有关的国际核保障中的挑战。为了确定可以加强现有气体离心浓缩厂保障措施和方法的位置，我们创建了一个离散时间模型，用于模拟假设的误用场景，包括瞬态阶段和稳态。我们发现，及时发现现代大型设施的滥用对国际保障措施构成了挑战。然而，无人值守测量系统的工具箱以及远程监控可用于提高检测的及时性，从而可能在快速的时间范围内启动后续活动。这些措施需要非常低的误报率，应以分级方式实施，这取决于每个浓缩厂的特点以及对其所在国的合理获取途径的分析。其中一些技术可以为工厂运营商带来显着的好处。