Mass-number and isotope dependence of local microscopic optical potentials for polarized proton scattering

We derive local microscopic optical potentials U systematically for polarized proton scattering at 65 MeV using the local-potential version of the Melbourne g-matrix folding model. As target nuclei, we take 6He and neutron-rich Ne isotopes in addition to stable nuclei of mass number A=4-208 in order to clarify mass-number and isotope dependence of U. The local potentials reproduce the experimental data systematically and have geometries similar to the phenomenological optical potentials for stable targets. The target density is broadened by the weak-binding nature and/or deformation of unstable nuclei. For the real spin-orbit part of U the density broadening weakens the strength and enlarges the radius, whereas for the central part it enlarges both of the strength and the radius. The density-broadening effect is conspicuous for halo nuclei such as 6He and 31Ne. Similar discussions are made briefly for proton scattering at 200 MeV. We briefly investigate how the isovector and the nonspherical components of U affect proton scattering.