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arXiv · hep-ph/0204178

Nucleon form factors from a covariant quark core: limits in their description

M. Oettel·R. Alkofer
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Abstract

In treating the relativistic three-quark problem, a dressed-quark propagator parameterization is used which is compatible with recent lattice data and pion observables. Furthermore two-quark correlations are modeled as a series of quark loops in the scalar and axialvector channel. The resulting reduced Faddeev equations are solved for nucleon and delta. Nucleon electromagnetic form factors are calculated in a fully covariant and gauge--invariant scheme. Whereas the proton electric form factor $G_E$ and the nucleon magnetic moments are described correctly, the neutron electric form factor and the ratio $G_E/G_M$ for the proton appear to be quenched. The influence of vector mesons on the form factors is investigated which amounts to a 25 percent modification of the electromagnetic proton radii within this framework.

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M. Oettel, R. Alkofer. 2002-04-16. Nucleon form factors from a covariant quark core: limits in their description. https://doi.org/10.1140/epja%2Fi2002-10070-4

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