Energy dependence of neutron scattering fromPb208in the energy range 7—50 MeV

Elastic neutron scattering from ${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}$ has been measured at 22.0 and 24.0 MeV and remeasured at 7.0 and 20.0 MeV with greatly improved precision. The present results and other neutron data in the energy range 7—50 MeV are analyzed in terms of a conventional, local optical model potential with the aim of studying energy dependence of the potential well depths. We find that the very detailed measurements of the present work made unusual demands on the geometrical parameters of the model. Improvements, if any, resulting from extension of the optical model parametrization to include a real surface term and imaginary spin-orbit term are tested. Concurrently with the elastic scattering experiments, inelastic scattering to the $3^{-}$ state at 2.615 MeV was measured at 7.0, 20.0, and 22.0 MeV. A distorted-wave Born approximation analysis is made of these data to extract octupole deformation parameters.