Symmetry dependence of the phenomenological optical model for neutron-nucleus scattering

We have determined the symmetry dependence of the central parr of the pheno menological optical model potential for neutron-nucleus scattering from abo ut 15 to 65 MeV. In contrast to the case for incident protons, we find evid ence that the symmetry dependence of the surface imaginary potential is neg ligible. When extended to higher energies, predictions of the model are in good agreement with measured neutron total cross sections for spherical nuc lei over a wide range of A and incident energy with no adjustment of parame ters.