Activation cross section measurements and estimation of photon and neutron induced nuclear reactions for ytterbium isotopes with covariance analysis

The cross sections of the Yb-168(n,2n)Yb-167, Yb-174(n,p)Tm-174, Yb-173(n,p)Tm-173, Yb-174(n,alpha)Er-171, Yb-170 (n,2n)Yb-169 and Yb-176(n,2n)Yb-175 nuclear reactions at 14.77 MeV neutron energy and the flux weighted average cross sections of the Yb-168(gamma,n)Yb-167, Yb-170(gamma,n)Yb-169 and( 176)Yb(gamma,n)Yb-175 nuclear reactions at 10 and 15 MeV bremsstrahlung endpoint energies are measured using offline gamma spectroscopy. The bremsstrahlung photon-induced reactions are reported for the first time at these energies. The results are compared with the evaluated nuclear data from the ENDF/B.-VIII.0, JEFF-3.3 and TENDL-2019 libraries. The theoretical model calculations are performed with the TALYS-1.95 nuclear code with parameters tuned to reproduce the measured data. The measured cross sections are in good agreement with the literature and evaluated data. The results are significant for the experimental nuclear database and reactor technology development.

Automated summary

This study measured the cross sections of multiple nuclear reactions at different energies using offline gamma spectroscopy and compared the results with evaluated nuclear data. The measured results are in good agreement with the literature and evaluated data, and are significant for the development of experimental nuclear databases and reactor technology.