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Sidewise dispersion relations and the structure of the nucleon vertex

R. M. Davidson·G. I. Poulis
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Abstract

We revisit sidewise dispersion relations as a method to relate the nucleon off-shell form factor to observable quantities, namely the meson-nucleon scattering phase shifts. It is shown how for meson-nucleon scattering a redefinition of the intermediate fields leaves the scattering amplitude invariant, but changes the behavior of the off-shell form factor as expressed through dispersion relations, thus showing representation dependence. We also employ a coupled-channel unitary model to test the validity of approximations concerning the influence of inelastic channels in the sidewise dispersion relation method.

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R. M. Davidson, G. I. Poulis. 1996-03-21. Sidewise dispersion relations and the structure of the nucleon vertex. https://doi.org/10.1103/physrevd.54.2228

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