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arXiv · 1510.05521

The pion-cloud contribution to the electromagnetic nucleon structure

D. Kupelwieser·W. Schweiger
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Abstract

The present contribution continues and extends foregoing work on the calculation of electroweak form factors of hadrons using the point-form of relativistic quantum mechanics. Here we are particularly interested in studying pionic effects on the electromagnetic structure of the nucleon. To this aim we employ a hybrid constituent-quark model that comprises, in addition to the $3q$ valence component, also a $3q$+$π$ non-valence component. With a simple wave function for the $3q$ component we get reasonable results for the nucleon form factors. In accordance with other authors we find that the pionic effect is significant only below $Q^2\lesssim 0.5$~GeV$^2$.

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D. Kupelwieser, W. Schweiger. 2015-10-19. The pion-cloud contribution to the electromagnetic nucleon structure. https://arxiv.org/abs/1510.05521

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