Dirac optical potentials for nucleon scattering byPb208at intermediate energies

We perform a global analysis of intermediate energy nucleon plus ${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}$ scattering data using the Dirac phenomenology. Proton elastic differential cross sections, analyzing powers, spin rotation functions, and total reaction cross sections, together with neutron total cross sections, spanning an incident energy range of 80–800 MeV, are used in the determination of a Dirac scalar-vector global potential. Two of six energy dependencies studied are selected to construct best-fit nucleon-nucleus potentials for the reduced incident-energy interval of 95–300 MeV. These potentials reproduce the experimental data uniformly within the reduced energy interval. Explicit values for the isovector strengths of the nucleon-nucleus potential are given. The correlations and ambiguities among the parameters of the potentials are studied. Predictions are made for the elastic differential cross section and spin observables for neutron plus ${}_{}{}^{208}{}_{}{}^{}\mathrm{Pb}$ scattering.