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Off-Shell Structures of Nucleon-Nucleon t-matrices and their Influence on Nucleon-Nucleus Elastic Scattering Observables

S. P. Weppner·Ch. Elster·D. Hueber
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Abstract

The sensitivity of nucleon-nucleus elastic scattering observables to the off-shell structure of nucleon-nucleon t-matrices, derived from realistic NN potentials, is investigated within the context of a full-folding model based on the impulse approximation. Our study uses recently developed NN potential models, which describe a subset of the NN data base with a $χ^2$ per datum $\sim$1, which means that the NN t-matrices are essentially on-shell equivalent. We calculate proton-nucleus elastic scattering observables for $^{16}$O, $^{40}$Ca, and $^{208}$Pb between 100 and 200 MeV laboratory energy. We find that the elastic scattering observables are insensitive to off-shell differences of the employed NN t-matrices. A more detailed investigation of the scattering equation and the optical potential as given in a factorized approximation reveals that the elastic scattering observables do not sample the NN t-matrices very far off-shell where they exhibit differences.

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S. P. Weppner, Ch. Elster, D. Hueber. 1997-11-29. Off-Shell Structures of Nucleon-Nucleon t-matrices and their Influence on Nucleon-Nucleus Elastic Scattering Observables. https://doi.org/10.1103/physrevc.57.1378

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