PRODUCTION CROSS SECTIONS OF Pa AND Th VIA 20.9 MeV PROTON IRRADIATION OF Th

This study presents the production cross sections of Pa resulting from proton irradiation of Th at an energy of 20.9 MeV. In addition, the excitation functions of Pa and Th produced via proton-induced reactions on Th in the energy range from 0.02 to 1.6 GeV are analyzed, with consideration of the possible contribution of secondary neutrons to their formation. The production cross sections for all reaction products were measured using direct gamma-ray spectrometry without chemical separation. The obtained experimental data are compared with results reported by other authors, as well as with calculated excitation functions generated using the PHITS-3.31 code (INCL4.6/GEM, JAM, and Bertini models) and the TENDL-2023 nuclear data library.