Measurement of Cross Sections for Reactions Th(He, )Pa, Th(He, )Pa, Th(He, )Pa, and Th(He, )U Induced by the Irradiation of ThO Targets with He

At present, the radioisotope U is considered as one of the most promising -emitters for application in immunotherapy. In order to refine nuclear data and to evaluate the efficiency of U production, the cross sections for the reactions Th( He, ) U and Th( He, ) U, as well as the cross sections for the accompanying reactions Th( He, ) Pa and Th( He, ) Pa, were measured for the first time in the range of energies of He nuclei between 30 and 62 MeV. The activation technique was used to measure the reaction cross sections. The experimental cross sections were compared with data from the TENDL-2021 library. The results give grounds to conclude that the reactions Th( He, ) U and Th( He, ) U cannot ensure efficient production of U at the U-150 cyclotron of National Research Center Kurchatov Institute. Therefore, they cannot be viewed as an alternative to proton- and deuteron-induced reactions producing U.