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arXiv · hep-ph/0110097

Polarized light-antiquark distributions in a meson-cloud model

S. Kumano·M. Miyama
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Abstract

Flavor asymmetry is investigated in polarized light-antiquark distributions by a meson-cloud model. In particular, rho meson contributions to Delta u-bar - Delta d-bar are calculated. We point out that the g_2 part of rho contributes to the structure function g_1 of the proton in addition to the ordinary longitudinally polarized distributions in rho. This kind of contribution becomes important at medium x (>0.2) with small Q^2 (~1 GeV^2). Including N->rho N and N->rho Delta splitting processes, we obtain the polarized rho effects on the light-antiquark flavor asymmetry in the proton. The results show Delta d-bar excess over Delta u-bar, which is very different from some theoretical predictions. Our model could be tested by experiments in the near future.

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S. Kumano, M. Miyama. 2001-10-06. Polarized light-antiquark distributions in a meson-cloud model. https://doi.org/10.1103/physrevd.65.034012

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