Phase Variation Effect on Proton - Nucleus Elastic Scattering

Abstract

Proton–deuteron elastic scattering at intermediate and high energies illustrates the importance of the phase variation of the nucleon–nucleon elastic scattering amplitude as in previous work. Two kinds of phase variation are examined. The first is the usual one which is related to free nucleon-free nucleon collisions as suggested by Franco. The second is assumed to be related to the time ordering of multi-scattering processes. The two kinds play similar roles in improving the results. The contributions of both kinds lead to a good fit to the experimental data at the energies considered. The value of the phase variation parameter in each kind (where they are considered together), which gives a good fit to the experimental data, are approximately the same and of order 4 (GeV / c)‾ 2. Also, with relatively small values of the phase variation parameter, the phase variation effect improves the agreement with the experimental data for the p–4He elastic scattering differential cross section at the minimum region in the energy range 97–393 GeV.