Neutron-Induced Partial Gamma-Ray Cross-Section Measurements on Uranium Using a Monoenergetic and Pulsed Beam at TUNL

An experimental program is being carried out at TUNL to study (n,2n) excitation functions on actinide nuclei using monoenergetic neutrons with the goal of improving the partial cross-section data for the NNSA Stockpile Stewardship Program. Measurements have been performed on $^{235,238}$U targets in the TUNL shielded neutron source area using a pulsed neutron beam with incident neutron energies between 5 and 18 MeV. The resultant emitted gamma rays are measured using different types of HPGe detectors. More than thirty (n,n') and (n,2n) partial cross-sections have been measured in this energy range, and experimental results will be compared with the Hauser-Feshbach model. A more in-depth explanation of the experimental techniques and analysis will be presented.