New experimental data on excitation functions of He 3 -induced nuclear reactions on Ta up to 27 MeV

Excitation functions of He-3-induced nuclear reactions on Ta-nat were measured utilizing the MGC-20E cyclotron, stacked-foils activation technique, and high-resolution gamma-ray spectrometry. From their threshold , energies up to 27 MeV, cross sections for( nat)Ta(He-3, xn) Re-182(m) Re-182(g), Re-181, and Ta-nat (He-3, alpha xn) Ta-178(A), Ta-180(g) reactions were measured. The half-life of the radionuclide 181 Re was checked experimentally. The intensity of the energy line 360.7 keV, in the radionuclide Re-181 decay scheme, was revised experimentally. The new experimental intensity represents about half the reported value in the different nuclear structure databases. The nuclear reaction codes TALYS-1.9 and EMPIRE-3.2.3 were used to predict the formation of these products. The isomeric cross-section ratio for the Re-182(m,g) was also calculated. The ratio indicates that the pre-equilibrium mechanism is dominant at energies over 19 MeV. Various combinations of the models' parameters implemented in EMPIRE such as nuclear level density models, optical model, and pre-equilibrium parameters were used to reproduce the experimental excitation functions. For TALYS calculations, the TENDL-2019 nuclear data library based on TALYS-1.9 was used. The present data were compared to theoretical results and the available experimental data. Integral yields for the produced radioisotopes were determined.