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arXiv · hep-ph/9809487

Flavor asymmetry of polarized and unpolarized sea quark distributions in the large-N_c limit

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

We summarize recent attempts to calculate the flavor asymmetry of the nucleon's sea quark distributions in the large-$N_c$ limit, where the nucleon can be described as a soliton of an effective chiral theory. We discuss the leading-twist longitudinally polarized and transversity antiquark distributions, $Δ\bar u (x) - Δ\bar d (x)$ and $δ\bar u (x) - δ\bar d (x)$, as well as the unpolarized one, $\bar u (x) - \bar d (x)$, which appears only in the next-to-leading order of the $1/N_c$-expansion. Results for $\bar u (x) - \bar d (x)$ are in good agreement with the recent Drell-Yan data from the FNAL E866 experiment. The longitudinally polarized antiquark asymmetry, $Δ\bar u (x) - Δ\bar d (x)$, is found to be larger than the unpolarized one.

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B. Dressler, K. Goeke, P. V. Pobylitsa, M. V. Polyakov, T. Watabe, C. Weiss. 1998-09-22. Flavor asymmetry of polarized and unpolarized sea quark distributions in the large-N_c limit. https://arxiv.org/abs/hep-ph/9809487

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