ASSESSMENT OF THE PERFORMANCE OF GAMMA/X-RAY/WEIGHING METHODS FOR THE QUANTITATIVE ASSAY OF NUCLEAR MATERIALS

The possibilities to determine simultaneously, from the same Gamma/X-ray spectrum, the isotopic vector and the mass fraction would represent for NDA (and for the entire Safeguards domain) an important step forward allowing the mass assay of both U and Pu bearing materials more easily, reliably and accurately than the existing NDA methods. The availability of a complete NDA assay onsite would strongly reduce the necessity for shipment and further expensive analyses of samples, improve the timeliness of measurements and reduce the cost of safeguards sample analyses. The spectra used for analyses came from different laboratories (IAEA, JRC, LANL) and have been analyzed with the algorithms and codes provided by IAEA, where they have been developed and are under test use. The task of assessing the possibilities of the new approach has been given to the Università “La Sapienza” of Rome by JRC-Ispra, in the frame of the Support Program to IAEA.