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arXiv · hep-ph/9804436

Isovector unpolarized quark distribution in the nucleon in the large-N_c limit

P. V. Pobylitsa·M. V. Polyakov·K. Goeke·T. Watabe·C. Weiss
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Abstract

We calculate the isovector (flavor-nonsinglet) unpolarized quark- and antiquark distributions in the nucleon at a low normalization point in the large-N_c limit. The nucleon is described as a soliton of the effective chiral theory. The isovector distribution appears in the next-to-leading order of the 1/N_c-expansion. Numerical results for the quark- and antiquark distributions compare well with the parametrizations of the data at a low normalization point. This large-N_c approach gives a flavor asymmetry of the antiquark distribution (violation of the Gottfried sum rule) in good agreement with the measurements.

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P. V. Pobylitsa, M. V. Polyakov, K. Goeke, T. Watabe, C. Weiss. 1998-04-28. Isovector unpolarized quark distribution in the nucleon in the large-N_c limit. https://doi.org/10.1103/physrevd.59.034024

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