JAEA-JRC Collaborative Development of Delayed Gamma-ray
Spectroscopy for Nuclear Safeguards Nuclear Material Accountancy

The Integrated Support Center for Nuclear Nonproliferation and Nuclear Security (ISCN) of the Japan Atomic Energy Agency (JAEA) initiated a project to develop Delayed Gammaray Spectroscopy (DGS) in 2015. Concurrently, the Joint Research Centre of the European Commission (EC/JRC) joined the JAEA/ISCN in collaborative experimentation. The primary goal of the DGS collaboration is to enhance analytical capabilities and instrumentation to improve the material accountancy of mixed nuclear materials. Preliminary research focused on experimental evaluation to observe differences in standard U and Pu samples. Subsequent efforts focused on understanding the correlated instrumentation to obtain viable signatures to distinguish the fissile nuclide composition. Our current efforts are to finalize the instrumentation and associated analysis required to efficiently determine the mass content in irradiated fuel. This work will describe the efforts made in this JAEA/ISCN-EC/JRC collaboration to enable DGS to become a viable non-destructive assay method for safeguards capabilities. Specifically, we will describe the lessons learned used for the final JAEA/ISCN instrument design from experiments performed in EC/JRC Ispra, analytical verification and model design validation experiments performed jointly in EC/JRC Geel, and spectral evaluations performed in both EC/JRC and JAEA/ISCN laboratories.