Phase variation of the nucleon-nucleon amplitudes and non-eikonal propagation

Previous authors have shown that introducing a phase variation of the nucleon-nucleon amplitude with momentum transfer greatly improves Glauber calculations of elastic scattering differential cross sections among light nuclei. The improvement is particularly striking at high momentum transfer. This phase variation being undetectable at the nucleon-nucleon level, its origin as a many-body effect is a challenging problem. In the present work we study its possible connection to non-eikonal propagation. (author)