Development of a prototype hybrid L-edge/L-XRF densitometer for nuclear fuel assay.

The hybrid L-edge/L-XRF densitometer (HLED) was developed for on-site nuclear fuel assays intended for safeguards purpose. The HLED can simultaneously measure both X-ray photon transmissions and characteristic X-ray emissions, which characterizes the elemental composition of samples of interest to determine the concentration of actinide-bearing materials, such as plutonium and uranium, in a nuclear fuel. A prototype of the HLED equipment was fabricated and tested to study the feasibility of nuclear material assays using a surrogate material (lead) to avoid radiation effects from nuclear materials. The uncertainty of the L-edge and L-XRF characteristics of the sample material are discussed in the article.