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arXiv · 1701.01662

Up- and down-quark contributions to the nucleon electromagnetic form factors at low $Q^2$

I. A. Qattan·J. Arrington
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Abstract

The spatial distribution of charge and magnetization within the nucleon (proton and neutron) is encoded in the elastic electromagnetic form factors $G_E^{(p,n)}$ and $G_M^{(p,n)}$. These form factors have been precisely measured utilizing elastic electron scattering, and the combination of proton and neutron form factors allows for the separation of the up- and down-quark contributions to the nucleon form factors. We expand on our original analyses and extract the up- and down-quark contributions to the nucleon electromagnetic form factors from worldwide data with an emphasis on precise new data covering the low-momentum region, which is sensitive to the large-scale structure of the nucleon. From these, we construct the flavor-separated Dirac and Pauli form factors and their ratios, and compare the results to recent extractions and theoretical calculations and models.

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I. A. Qattan, J. Arrington. 2017-01-05. Up- and down-quark contributions to the nucleon electromagnetic form factors at low $Q^2$. https://doi.org/10.1088/1742-6596/869/1/012053

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