ANGULAR DISTRIBUTION OF 5.45 Mev PROTONS SCATTERED ELASTICALLY BY NICKEL, COPPER AND COBALT ISOTOPES

Angular distributions of protons elastically scattered by Co/sup 59/, Ni/ sup 58/, Ni/sup 60/, Ni/sup 62/, Ni, and Cu/sup 65/ at 5.45 Mev, which is about 1.5 Mev below potential level, were measured. The variable results for sub- barrier energy protons elastic scattering on even-even and odd-odd isotopes indicate specific nucleon-nuclei interaction for each nuclide. Consequently the optical model, even with supplementary spinorbit sign in the interaction potential, cannot satisfactorily describe nucleon-nucleus interactions. (R.V.J.)