LAUSR

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.