Discrimination of spent nuclear fuels in nuclear forensics through isotopic fingerprinting

• Discrimination of spent fuel with forensic importance.
• Isotopic fingerprinting method on the basis of U and/or Pu isotopic compositions.
• Compositions from the OECD/NEA SFCOMPO databank with commercial nuclear reactors.
• Method sensitive enough to resolve spent fuels from different reactors.
• Dependence of discrimination on core position of fuel.

Isotopic fingerprinting in nuclear forensics, developed through a simulation study to resolve spent nuclear fuels from different reactors, has been applied on real samples from fuels irradiated in nuclear reactors. The U and Pu isotopics of the real samples, used as fingerprints, have been retrieved from the OECD/NEA SFCOMPO databank comprising compositions of spent nuclear fuels from their Post-Irradiation Examination at the End of their Irradiation (EOI). The method has grouped together nuclear spent fuels from the same reactor, resolving distinctly those with similar 235U enrichment. Furthermore, spent fuel pins of the same enrichment, from different positions within a reactor core, are resolved. Differentiating of the spent fuels has been achieved, whether (U, Pu) or Pu are used as fingerprints.