Nuclear nonproliferation measurements performed on mixed-oxide fuel pins at the Idaho National Laboratory

New results are presented on the passive measurement of mixed-oxide fuel pin assemblies. A fast and robust methodology for the characterization of mixed-oxide fuel pins is discussed. Four EJ-309 liquid scintillation detectors coupled with an accurate pulse timing and digital, offline, optimized pulse-shape discrimination method were used. Measurement analysis including pulse-height distributions and time-dependent cross-correlation functions were performed. The use of Monte Carlo particle transport codes, specifically MCNP-PoliMi, is discussed in conjunction with the anticipated measurements.