New cross section measurements on tungsten isotopes around 14 MeV neutrons and their excitation functions * *Supported by the National Natural ScienceFoundation of China (11575090)

Abstract

New cross sections of the 183W(n,α)180mHf, 186W(n,d*)185Ta, 182W(n,p)182Ta, 184W(n,p)184Ta, 182W(n,2n)181W, 184W(n,α)181Hf, and 186W(n,α)183Hf reactions were measured in the neutron energy range of 13.5-14.8 MeV via the activation technique to improve the database and resolve discrepancies. Monoenergetic neutrons in this energy range were produced via the T(d,n)4He reaction on a solid Ti-T target. The activities of the irradiated monitor foils and samples were measured using a well-calibrated high-resolution HPGe detector. Theoretical calculations of the excitation functions of the seven nuclear reactions mentioned above in the neutron energies from the threshold to 20 MeV were performed using the nuclear theoretical model program TALYS-1.9 to aid new evaluations of cross sections on tungsten isotopes. The experimental data obtained were analyzed and compared with that of previous experiments conducted by other researchers, and with the evaluated data available in the five major evaluated nuclear data libraries of IAEA (namely ENDF/B-VIII.0 or ENDF/B-VII.0, JEFF-3.3, JENDL-4.0u+, CENDL-3.2, and BROND-3.1 or ROSFOND-2010), and the theoretical values acquired using TALYS-1.9 nuclear-reaction modeling tools. The new cross section measurements agree with those of some recent experiments and theoretical excitation curves at the corresponding energies. The consistency of the theoretical excitation curves based on TALYS-1.9 with these experimental data is better than that of the evaluated curves available in the five major nuclear data libraries of IAEA.