Validation of MA nuclear data by sample irradiation experiments with the fast reactor JOYO

This paper presents validation work on MA nuclear data by PIE analyses in the framework of fast-reactor cycle system development. The PIE analyses are in progress on MA samples (Np-237, (241)AM, Am-243, (CM)-C-244) irradiated at the experimental fast reactor "JOYO." The preliminary analysis results showed that the isomeric ratio for Am-241 capture reaction lies at around 0.85 (g/(g+m)) in the fast-neutron spectra, which suggested the necessity of re-evaluation of the data both in ENDF/B-VI and in JENDL-3.3. From the results on curium isotopes, overestimations could be pointed out for the capture cross section of (CM)-C-244 in ENDF/B-VI and that of (CM)-C-241 in JENDL-3.3.