Abstract As the IAEA has applied integrated safeguards and a state level approach to member states, the importance of national inspection has increased. However, the requirements for national inspection for some member states are different from the IAEA safeguards. In particular, the national inspection for the ROK requires on-site U concentration analysis due to a domestic notification. This research proposes an on-site U concentration analysis (OUCA) method for UO2 pellets using gamma spectroscopy to satisfy the domestic notification requirement. The OUCA method calculates the U concentration of UO2 pellets using the measured net X-ray counts and declared 235U enrichment. This research demonstrates the feasibility of the OUCA method using both MCNP simulation and experiment. It simulated and measured the net X-ray counts of different UO2 pellets with different U concentrations and 235U enrichments. The simulated and measured net X-ray counts were fitted to polynomials as a function of U concentration and 235U enrichment. The goodness-of-fit results of both simulation and experiment demonstrated the feasibility of the OUCA method.

中文翻译：

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使用伽马能谱研究 UO2 球团的新型现场 U 浓度分析方法

摘要 随着 IAEA 对成员国实施综合保障监督和国家级方法，国家检查的重要性增加了。但是，一些成员国的国家检查要求与IAEA的保障措施不同。尤其是韩国的国检，由于国内通报，需要进行现场U浓度分析。本研究提出了一种使用伽马光谱对 UO2 球团进行现场 U 浓度分析 (OUCA) 的方法，以满足国内的通报要求。OUCA 方法使用测量的净 X 射线计数和声明的 235U 富集来计算 UO2 颗粒的 U 浓度。本研究使用 MCNP 模拟和实验证明了 OUCA 方法的可行性。它模拟并测量了具有不同 U 浓度和 235U 富集度的不同 UO2 颗粒的净 X 射线计数。模拟和测量的净 X 射线计数被拟合为多项式，作为 U 浓度和 235U 富集的函数。模拟和实验的拟合优度结果证明了 OUCA 方法的可行性。