Cross Sections, Transition Schemes, and Branching Ratios for ²³²Th from the 232Th(n,n 'γ) Reaction

Neutron inelastic scattering from ²³²Th has been studied for states above 700 keV in excitation using the (n,n'γ) technique at incident energies in the 0.77- to 2.10-MeV range. The gamma-ray measurements employing a high-resolution Ge(Li) spectrometer show 74 transitions from 46 levels above the first excited state. Gamma-ray branching ratios and production cross sections have been determined. Inferred level cross sections are compared to compound-nucleus statistical model calculations, which generally represent the measurements fairly well at lower incident energies but become increasingly discrepant at higher bombarding energies, and to the ENDF/B-V evaluation.