A screening and prioritisation framework for medical radionuclide production in medium-power research reactors

The increasing demand for medical radionuclides highlights the need for more diversified and resilient production strategies. This work presents a systematic methodology for prioritising medical radionuclides for production in medium-power research reactors under constrained neutron-flux conditions. An integrated multi-criteria assessment methodology is presented, combining neutron transport and activation calculations with activity-demand considerations, decay losses, radionuclidic impurity evolution, achievable molar activity, target availability, reactor-operational constraints, and radiochemical processing requirements. The methodology is applied to the ENEA TRIGA RC-1 research reactor, currently the highest-power nuclear research facility operating in Italy, as a representative medium-flux research reactor. The robustness of the methodology is evaluated through Monte Carlo sensitivity analyses performed over different weighting configurations and three reference activity-demand scenarios. The results show that only a limited subset of radionuclides remains consistently favourable for production when neutron-physics, operational and processing-related constraints are considered simultaneously, while the overall prioritisation remains largely insensitive to weighting assumptions and reference activity scenarios. Rather than assessing competitiveness with established large-scale production infrastructures, the proposed approach provides a systematic decision-support framework for identifying those radionuclides that warrant subsequent experimental, radiochemical and techno-economic investigations in medium-power research reactors.