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arXiv · 1810.06035

Electromagnetic currents of the pion-nucleon system

T. Skawronski·B. Blankleider·A. N. Kvinikhidze
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Abstract

Pion photoproduction amplitudes are calculated from a set of equations that have been derived by coupling an external photon to all places in a dressed pion-nucleon vertex. The calculation is consistent with gauge invariance, charge conservation, unitarity and covariance. To provide input to the photoproduction amplitude, a photon-nucleon vertex is calculated from a set of equations derived by complete attachment of photons to a dressed nucleon propagator. We check the accuracy of this vertex by extracting its nucleon electromagnetic form factors.

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T. Skawronski, B. Blankleider, A. N. Kvinikhidze. 2018-10-14. Electromagnetic currents of the pion-nucleon system. https://doi.org/10.1103/physrevc.99.034001

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