Quality control tools for age dating in nuclear safeguards and forensics

Abstract

Nuclear safeguards conclusions are based to a large extent on comparison of measurement results between operator and safeguards laboratories. Nuclear forensics deals with consistency of information, coherence between materials or samples, conformity of findings with declared processes and comparison of external and internal data. Representative samples are measured by respective networks of laboratories. For nuclear safeguards these are the Euratom safeguards and the IAEA Network of Analytical laboratories (IAEA-NWAL). For nuclear forensics, the laboratories are mainly members of the Nuclear Forensics International Technical Working Group (ITWG). Metrological quality control tools are a means to establish accurate, traceable and comparable measurement results. The European Commission-Joint Research Centre (EC-JRC) has therefore put effort into the development of certified reference materials and the provision of conformity assessment tools, particularly for "age-dating" of uranium and plutonium samples, which is of importance to both communities. In this context the new IRMM-1000a and IRMM-1000b, certified for the production date based on the 230Th/234U radiochronometer, will be presented, and the results from the Regular European Inter-laboratory Measurement Evaluation Programme (REIMEP-22) on 'U Age Dating' will be discussed. Furthermore the status of the on-going development of a 243Am spike reference material in the frame of the recently signed collaboration agreement between the EC-JRC and the CEA/DEN will be presented. This spike is intended for use in the determination of the last separation date of plutonium samples by Isotope Dilution Mass Spectrometry (IDMS) using the 241Pu/241Am radiochronometer.JRC.G.2-Standards for Nuclear Safety, Security and Safeguar