Education and Training Series #84: Characterization of U-233 for Thorium Fuel Cycle Safeguards

These webinars, organised by the GIF Education and Training Working Group are streamed live monthly. The recordings and slide decks are accessible after the webinar on this website. These webinars cover a very broad range of technical and policy related topics. At the end of 2023 they have been viewed by more than 15000 people (approximately half of the views during the live streams and the other half views being of the archives on the public GIF website). In total, the GIF webinars have reached Generation IV enthusiasts, scientists, and engineers in more than 80 countries.

These webinars are organised and hosted by the GIF Education and Training Working Group (ETWG). 

Renewed international interest in thorium-fueled advanced reactors has challenged the safeguards community to address future proliferation concerns. Thorium-based technology presents many benefits but does not eliminate the proliferation risks associated with producing and processing fissile material. A byproduct of thorium-fueled reactors is uranium-233, which is classified as a direct-use material. As a result, the development of new or improved methods to characterize and measure materials containing 233U must mirror the pace of development of reactors and facilities that produce such material. Research is underway to assess, develop, and test approaches for safeguarding nuclear materials within the thorium fuel cycle. Neutron signatures from the nondestructive assay (NDA) of materials containing 233U and 235U are being quantified to inform the potential characterization of these materials. Using a traditional neutron coincidence counter and a series of well-documented 233U oxide samples, initial measurements have been made to assess the feasibility of 233U characterization and discrimination from other uranium isotopes, primarily 235U, using a combination of measurement techniques and analysis methods. Data acquisition is performed in list mode, allowing for a variety of analyses to be performed on the raw data that is not available using traditional shift register technology. Measurements were performed with an Active Well Coincidence Counter (AWCC) in passive and active configurations to quantify the strength of signals and validate simulations to demonstrate feasibility of a novel characterization technique.