Nucleon Spin Content from Elastic Form Factor Data
نویسنده
چکیده
I use the formalism of skewed parton distributions (SPD) to describe elastic form factors of the nucleon. The results are consistent with approximate dipole behavior of GMp(Q ) and recent JLab data for the ratio of the proton form factors GEp/GMp at Q 2 ≤ 3.5 GeV. Using the Angular Momentum Sum Rule, I obtain a numerical estimate for the valence quark contributions to the nucleon spin at the level of 50%, with their orbital angular momentum included. When combined with polarized DIS measurements, this result indicated that the orbital angular momentum of quarks contributes about 25% to the nucleon spin.
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