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Sensitivity of nucleon-nucleus scattering to the off-shell behavior of on-shell equivalent NN potentials

H. F. Arellano·F. A. Brieva·M. Sander·H. V. von Geramb
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Abstract

The sensitivity of nucleon-nucleus elastic scattering to the off-shell behavior of realistic nucleon-nucleon interactions is investigated when on-shell equivalent nucleon-nucleon potentials are used. The study is based on applications of the full-folding optical model potential for an explicit treatment of the off-shell behavior of the nucleon-nucleon effective interaction. Applications were made at beam energies between 40 and 500 MeV for proton scattering from 40Ca and 208Pb. We use the momentum-dependent Paris potential and its local on-shell equivalent as obtained with the Gelfand-Levitan and Marchenko inversion formalism for the two nucleon Schroedinger equation. Full-folding calculations for nucleon-nucleus scattering show small fluctuations in the corresponding observables. This implies that off-shell features of the NN interaction cannot be unambiguously identified with these processes. Inversion potentials were also constructed directly from NN phase-shift data (SM94) in the 0-1.3 GeV energy range. Their use in proton-nucleus scattering above 200 MeV provide a superior description of the observables relative to those obtained from current realistic NN potentials. Limitations and scope of our findings are presented and discussed.

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H. F. Arellano, F. A. Brieva, M. Sander, H. V. von Geramb. 1996-05-07. Sensitivity of nucleon-nucleus scattering to the off-shell behavior of on-shell equivalent NN potentials. https://doi.org/10.1103/physrevc.54.2570

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