Neutron scattering in Ce-140,Ce-142 and strengths of neutrons and protons in collective levels of Ce-140 - art. no. 014606

Differential cross sections for 7.5 MeV neutron scattering from Ce-140,Ce-1 42 have been measured and analyzed in conjunction with previously known tot al cross sections between 0.5 and 10 MeV and scattering properties in the v ery low-energy or resonance region. The differential elastic scattering cro ss sections, total cross sections, and resonance-region properties enable u s to fix the mean scattering fields, so that the scattering amplitudes at t he nuclear surface are given with confidence. The inelastic scattering cros s sections are then analyzed to extract the excitation strengths of a few c ollective levels. The level-excitation strengths found in this neutron scat tering analysis provide insight into the 4(1)(+) level's configuration, and also have been compared to strengths observed in electron scattering and C oulomb excitation to separate the roles of protons and neutrons in 2(+), 3( -), and 4(+) levels excited in Ce-140.