Exploiting alpha particle induced reaction to produce terbium theranostic radioisotopes: cross-section determination up to 70 MeV

Most of the radionuclides used in nuclear medicine are produced via reactions induced by neutrons in nuclear reactors or by light charged particles (p or d). The use of α particles only finds limited applications due to two principal drawbacks: a lower production yield because of their short range in the target, and the limited availability of α particles beams accelerators. However, their use brings advantages including the easier radiochemical separation of the product, the atomic number of which can be two units higher than the target material. This is particularly true for radiolanthanides, the radiochemical separation of which is difficult. In this work we discuss the possibility to produce the theranostic terbium radioisotopes using alpha particle induced reactions on natural gadolinium targets and natural europium (III) oxide targets. The cross-sections have been determined using the stacked-foils technique and compared with theoretical simulations and with previous studies, when available. The energetic range up to 70 MeV allows to produce the Tb radioisotopes that are farther from the valley of stability in the nuclide chart, like 149Tb and 152Tb.