Theoretical study for a 117mSn production experiment with a 30 MeV α-beam cyclotron

Metastable Sn-117m is a promising theranostic radionuclide, suitable for SPECT diagnostic imaging and conversion electron therapy. Its production is based mainly on nuclear reactors, but there is increasing interest in alternative routes with cyclotrons. Theoretical studies are essential to identify the irradiation parameters and conditions to maximize its production, while minimizing the impact of the contaminants. The goal of this study is to investigate the production of Sn-117m with a 30MeV a beam on Cd-nat and In-nat targets, as provided by the HIL-UW (Heavy Ion Laboratory - University of Warsaw) U-200P cyclotron. We performed a theoretical analysis of cross section, yield and purity by means of two nuclear reaction codes: Talys (v.1.9), based on a combination of models, and Fluka (v.2018.2.dev), based on Monte Carlo simulations. We compared the theoretical calculations with both experimental data already known in the literature and preliminary results obtained at HIL. A statistical treatment of the models suggests a comparable production of Sn-117m for both targets, but a higher radionuclidic purity was found in the case of the In-nat target.