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arXiv · hep-ph/0407364

Strange quark asymmetry in the nucleon and the NuTeV anomaly

Johan Alwall·Gunnar Ingelman
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Abstract

The NuTeV anomaly of a non-universal value of the fundamental parameter sin^2θ_W in the electroweak theory has been interpreted as an indication for new physics beyond the Standard Model. However, the observed quantity depends on a possible asymmetry in the momentum distributions of strange quarks and antiquarks in the nucleon. This asymmetry occurs naturally in a phenomenologically successful physical model for such parton distributions, which reduces the NuTeV result to only about two standard deviations from the Standard Model.

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Johan Alwall, Gunnar Ingelman. 2004-12-15. Strange quark asymmetry in the nucleon and the NuTeV anomaly. https://doi.org/10.1103/physrevd.70.111505

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