Cerium-139 radionuclide production from proton-induced nuclear reaction on Lanthanum-139 target for diagnostic applications

As a monoenergetic gamma-ray emitter with a half-life of 137.63 days, Cerium-139 (Ce-139 or 139Ce) has been proposed as a diagnostic agent in nuclear medicine using Single Photon Emission Computed Tomography (SPECT). A large amount of Ce-139 is traditionally obtained from the fission products of uranium, but it is concerned with the presence of highly radioactive nuclear waste products. In this simulation study, Ce-139 is proposed to be produced by the bombardment of proton beams ranging from 5 to 30 MeV on a rare earth element, Lanthanum-139 (La-139 or 139La) target via 139La(p,n)139Ce nuclear reaction. The La-139 target was presumably a solid foil target with variable thicknesses ranging from 0.2 to 3 mm. The Ce-139 radioactivity yield was calculated analytically using the available nuclear cross-section data derived from the Talys Evaluated Nuclear Data 2021 (TENDL 2021). Based on the calculated results, a significant yield of 37 kBq/µAh begins to be expectedly detected when proton energy was 7 MeV. The yield increases further with increasing proton energy with a maximum yield of 1.073 MBq/µAh for a proton energy of 30 MeV. Significant radioactive impurities such as Ce-138 and La-138 were predicted to present during the Ce-139 radioisotope production.