IN-MEDIUM FULL-FOLDING OPTICAL-MODEL FOR NUCLEON-NUCLEUS ELASTIC-SCATTERING

We develop an approach for incorporating both medium and off-shell eff ects in the calculation of full-folding nucleon-nucleus optical potent ials for elastic scattering. The approach is based on a flexible schem e for calculating the nucleon-nucleon effective interaction in the nuc lear medium. Using this scheme, we calculate a fully off-shell, energy -dependent effective force which includes effects arising from Pauli b locking and the nuclear mean field via an interacting nuclear matter m odel. Calculations of the elastic scattering observables for p+Ca-40 a nd for p+Pb-208 at energies between 30 and 400 MeV are presented and d iscussed. We also study total cross sections for neutron scattering of f Ca-40, Zr-90, and Pb-208 in the 5 - 400 MeV energy range. The theory gives a reasonable overall description of the data in the energy rang e under study.