Validation of MCNP6 and FISPACT-II calculations to predict the activation of selected beta emitters produced in the Budapest Research Reactor

Activation calculations were completed on the production of emerging beta-emitting radionuclides in the Budapest Research Reactor (BRR) for medical applications. MCNP6 was utilized to characterize the neutron field at the irradiation positions, while FISPACT-II software was used to predict the activities of the produced radionuclides. Target materials with natural isotopic compositions were irradiated in three different vertical channels of the BRR, and the specific activities of the radionuclides 161 Tb, 111 Ag, 199 Au and 177 Lu were determined using gamma-ray spectrometry. The validation has been successfully completed using ENDF/B-VIII.0 and TENDL-2017 nuclear data libraries. A few discrepant cases were identified which require further investigation. • MCNP6 and FISPACT-II software were used jointly to predict the activation of 161 Tb, 111 Ag, 199 Au, 177 Lu and the methodology was validated with real experiments. • The highest production rates were achieved in the water trap irradiation channel. • Upscaling experiments confirmed the importance of using enriched target materials, especially in case of 161 Tb production.