Cross Sections for Production of 43Sc, 44Sc, and 46Sc Isotopes in the 45Sc

Reactions Sc-45(He-3, an) Sc-43, Sc-45(He-3, a) Sc-44, and Sc-45(He-3, 2p)Sc-46, resulting from the irradiation of scandium targets with a beam of He-3 ions with energy from 5 to 24 MeV, are investigated in experiments on the U120M cyclotron of the Nuclear Physics Institute (Rez, Czech Republic). The activation technique is used to find the yield of the produced Sc isotopes. The induced. activity in the targets is measured using a high-resolution HPGe detector. Despite the low binding energy of He-3 and positive reaction Q values, which leads to formation of the Sc-44 and Sc-46 isotopes, the behavior of the excitation functions for the formation of these isotopes differs from the behavior of the excitation function for deuterons. Scandium-44 formation cross sections reach their maximum at the reaction Coulomb barrier. This is because not only Sc-44 but also a stable He-4 nucleus is formed in the reaction.