Energy dependent production and radionuclidic purity of \(\:{\:}^{47}\mathbf{S}\mathbf{c}\:\)from \(\:{\:}^{48}\mathbf{C}\mathbf{a}(\varvec{p},\varvec{x}\varvec{n})\:\)reactions: a combined theoretical and data from EXFOR library using the EMPIRE code

Abstract

Background

The production of Scandium-47, a promising radionuclide for targeted radionuclide therapy, was investigated via proton-induced reactions on enriched Ca-48 using the EMPIRE nuclear reaction code. A comparative analysis between EMPIRE simulations and experimental data extracted from EXFOR was performed for Sc-48, Sc-47, and Sc-46 production channels, showing good overall agreement, as indicated by low MAPE values and correlation coefficients close to unity. Excitation functions for the ⁴⁸Ca(p, n)⁴⁸Sc, ⁴⁸Ca(p,2n)⁴⁷Sc, and ⁴⁸Ca(p,3n)⁴⁶Sc reactions were calculated over a wide proton energy range, and thick-target yields were evaluated using stopping power data. The RNP of ⁴⁷Sc was determined as a function of incident proton energy.

Results

The results show that radionuclide production strongly depends on proton energy. At low energies (0–12 MeV), the ⁴⁸Ca(p, n) reaction dominates, leading to significant ⁴⁸Sc formation and low RNP (~ 9%). In the intermediate energy range (12–28 MeV), the yield of ⁴⁷Sc increases substantially while maintaining relatively high purity. A more detailed analysis identifies the 16.5–21.5 MeV window as optimal, providing high yield with an RNP of approximately 94%. At higher energies (28–50 MeV), the increasing contribution of the ⁴⁸Ca(p,3n) reaction results in significant formation of long-lived ⁴⁶Sc, reducing radionuclidic purity.

Conclusion

These findings demonstrate that careful selection of the proton energy window is essential for optimizing both production yield and RNP, providing practical guidance for cyclotron-based production of ⁴⁷Sc for medical applications.