Polarized rho mesons and the asymmetry between Delta d^bar(x) and Delta u^bar(x) in the sea of the nucleon

Abstract

We present a calculation of the polarized rho meson cloud in a nucleon using time-ordered perturbation theory in two different variants advocated in the literature. We calculate the induced difference between the distributions Delta d^bar(x) and Delta u^bar(x). We use a recent lattice calculation to motivate an ansatz for the polarized valence quark distribution of the rho meson. Our calculations show that the two theoretical approaches give vastly different results. We conclude that Delta d^bar(x) - Delta u^bar(x) can be of relevant size with important consequences for the combined fits of polarized distribution functions.

14 pages LaTeX, 8 figures; v3: some minor changes; this preprint supports the version to appear in Phys. Lett. B with an additional appendix

References in corpus (4)

• Flavor Asymmetry of Antiquark Distributions in the Nucleon
• Pion and Rho Structure Functions from Lattice QCD
• Unpolarized and polarized quark distributions in the large-Nc limit
• The Skyrme Model piNN Form Factor and the Sea Quark Distribution of the Nucleon

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