Nuclear forensics on uranium fuel pellets

摘要

Nuclear forensic analysis of uranium oxide fuel pellets and the respective data interpretation have proven to be important elements of the investigative process when such material is found out of regulatory control. Uranium oxide fuel pellets are produced at industrial scale and have to meet tight technical specifications. Variations in the production process of different manufacturers or fuel fabrication facilities offer an additional source of information. The compilation of such information in a nuclear materials database has proven to be a highly valuable resource. In consequence, measureable material properties (referred to as “signatures”) such as the isotopic composition, the physical dimensions, the chemical impurities, the products of the radioactive decay of uranium and the microstructure allow establishing the processing history of the material. To this end, dedicated analytical methods have to be developed and suitable methods for data evaluation and interpretation need to be utilised. The successful application of these nuclear forensic tools is illustrated with two case studies on real incidents of illicit nuclear trafficking of uranium oxide fuel pellets.