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Electromagnetic form factors of the nucleon in chiral perturbation theory including vector mesons

Matthias R. Schindler·Jambul Gegelia·Stefan Scherer
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Abstract

We calculate the electromagnetic form factors of the nucleon up to fourth order in manifestly Lorentz-invariant chiral perturbation theory with vector mesons as explicit degrees of freedom. A systematic power counting for the renormalized diagrams is implemented using both the extended on-mass-shell renormalization scheme and the reformulated version of infrared regularization. We analyze the electric and magnetic Sachs form factors, $G_E$ and $G_M$, and compare our results with the existing data. The inclusion of vector mesons results in a considerably improved description of the form factors. We observe that the most dominant contributions come from tree-level diagrams, while loop corrections with internal vector meson lines are small.

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Matthias R. Schindler, Jambul Gegelia, Stefan Scherer. 2005-09-01. Electromagnetic form factors of the nucleon in chiral perturbation theory including vector mesons. https://doi.org/10.1140/epja%2Fi2005-10145-8

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