The global phase of the nucleon-nucleon amplitudes and proton-nucleus scattering

Evidence for a global phase variation of the nucleon-nucleon amplitudes has been investigated at intermediate energies in the elastic scattering of protons, deuterons, 3He and 4He. Extending previous works, we study the influence of this phase variation on the proton-nucleus scattering for heavier systems. As a specific example, calculations have been performed for p-12C elastic and inelastic scattering at 0.8 GeV. The present work being exploratory in nature, we simply used the Kerman, McManus and Thaler approximation to the optical potential. (Author)