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arXiv · hep-ph/9809255

Valence Quark Spin Distribution Functions

Nathan Isgur
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Abstract

The hyperfine interactions of the constituent quark model provide a natural explanation for many nucleon properties, including the Delta-N splitting, the charge radius of the neutron, and the observation that the proton's quark distribution function ratio d(x)/u(x)->0 as x->1. The hyperfine-perturbed quark model also makes predictions for the nucleon spin-dependent distribution functions. Precision measurements of the resulting asymmetries A_1^p(x) and A_1^n(x) in the valence region can test this model and thereby the hypothesis that the valence quark spin distributions are "normal".

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Nathan Isgur. 1998-09-03. Valence Quark Spin Distribution Functions. https://doi.org/10.1103/physrevd.59.034013

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