Utilizing PUNITA experiments to evaluate fundamental delayed gamma-ray spectroscopy interrogation requirements for nuclear safeguards

Rodriguez, D. ; Koizumi, Mitsuo ; Rossi, F. ; Seya, Michio; Takahashi, Tone; Bogucarska, T.*; Crochemore, J.-M.*; Pedersen, B.*; Takamine, Jun 

Present safeguards verification methods of high-radioactivity nuclear material use destructive analysis techniques since passive nondestructive techniques are incapable of determining the nuclear material content. To improve this verification process, the JAEA and EC-JRC Ispra, Italy have been collaborating to develop delayed gamma-ray spectroscopy for composition analysis of the fissile nuclides as an aspect of the MEXT subsidy for improving nuclear security and the like. Multiple experiments were performed over three years using PUNITA to interrogate U and Pu samples to determine the signature from the short-lived fission products. We observed many gamma rays useful to determine the composition of a mixed nuclear material sample. Presented here are the results of these measurements with correlations to the interrogation, mass, volume, and sample homogeneity.