Abstract
Information on the non perturbative content of the proton state, in particular on the non valence contribution, could be extracted from the analysis of the ratio between the electric and magnetic form factors of the proton, given the highly accurate data from JLAB, obtained in the past and available in the very close future. This possibility is illustrated within our approach based on an Ansatz for the Bethe-Salpeter amplitude describing the quark-nucleon vertex and a Vector Meson Dominance model for the quark-photon one. After presenting a short review of our approach, able to predict the presence of a zero in the above ratio with only four free parameters fixed by three spacelike nucleon form factors, we give preliminary results for the nucleon timelike polarizations, that are quite sensitive to the Vector meson spectra.
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Salmè, G., Frederico, T. & Pace, E. Does \({\mu_p G^p_E/ G^p_M}\) Open a New Window on the Proton Non Valence Sector?. Few-Body Syst 56, 303–309 (2015). https://doi.org/10.1007/s00601-015-1002-z
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DOI: https://doi.org/10.1007/s00601-015-1002-z