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arXiv · 1401.1705

On the Momentum Dependence of the Flavor Structure of the Nucleon Sea

Jen-Chieh Peng·Wen-Chen Chang·Hai-Yang Cheng·Tie-Jiun Hou·Keh-Fei Liu·Jian-Wei Qiu
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Abstract

Difference between the $\bar u$ and $\bar d$ sea quark distributions in the proton was first observed in the violation of the Gottfried sum rule in deep-inelastic scattering (DIS) experiments. The parton momentum fraction $x$ dependence of this difference has been measured over the region $0.02 < x < 0.35$ from Drell-Yan and semi-inclusive DIS experiments. The Drell-Yan data suggested a possible sign-change for $\bar d(x)-\bar u(x)$ near $x \sim 0.3$, which has not yet been explained by existing theoretical models. We present an independent evidence for the $\bar d(x)-\bar u(x)$ sign-change at $x \sim 0.3$ from an analysis of the DIS data. We further discuss the $x$-dependence of $\bar d(x)-\bar u(x)$ in the context of meson cloud model and the lattice QCD formulation.

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Jen-Chieh Peng, Wen-Chen Chang, Hai-Yang Cheng, Tie-Jiun Hou, Keh-Fei Liu, Jian-Wei Qiu. 2014-07-28. On the Momentum Dependence of the Flavor Structure of the Nucleon Sea. https://doi.org/10.1016/j.physletb.2014.07.050

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