Strange quark asymmetry in the nucleon and the NuTeV anomaly

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.

4 pages, 5 figures, RevTex4. Updated with new references and extended discussion. v.3: Minor corrections made