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Electromagnetic form factors of the nucleon in spacelike and timelike regions

J. P. B. C. de Melo·T. Frederico·E. Pace·S. Pisano·G. Salme`
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Abstract

An approach for a unified description of the nucleon electromagnetic form factors in spacelike and timelike regions is presented. The main ingredients of our model are: $i)$ a Mandelstam formula for the matrix elements of the nucleon electromagnetic current; $ii)$ a 3-dimensional reduction of the problem on the Light-Front performed within the so-called {\tt Propagator Pole Approximation} ({\bf PPA}), which consists in disregarding the analytical structure of the Bethe-Salpeter amplitudes and of the quark-photon vertex function in the integration over the minus components of the quark momenta; $iii)$ a dressed photon vertex in the $q\bar{q}$ channel, where the photon is described by its spin-1, hadronic component.

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J. P. B. C. de Melo, T. Frederico, E. Pace, S. Pisano, G. Salme`. 2006-12-13. Electromagnetic form factors of the nucleon in spacelike and timelike regions. https://doi.org/10.1142/9789812708793_0026

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