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Radiatively Generated Isospin Violations in the Nucleon

M. Glück·P. Jimenez-Delgado·E. Reya
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Abstract

Isospin violating valence and sea distributions are evaluated due to QED leading ${\cal{O}}{(α)}$ corrections to the standard QCD evolution equations. Unique perturbative predictions are obtained within the radiative parton model, and confirm earlier results. Nonperturbative contributions have been estimated and depend on a single free parameter chosen to be the current quark mass.The relevance of our predictions for extracting $\sin^2 θ_W$ from DIS $ν(\barν)N$ data (`NuTeV anomaly') is discussed as well.

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M. Glück, P. Jimenez-Delgado, E. Reya. 2005-02-17. Radiatively Generated Isospin Violations in the Nucleon. https://arxiv.org/abs/hep-ph/0501169

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