Effect of asymmetric strange–antistrange sea to the NuTeV anomaly

Abstract

We calculate the strange quark and antiquark distributions of the nucleon by using the effective chiral quark model, and find that the strange–antistrange asymmetry can bring a contribution of about 60–100% to the NuTeV deviation of sin2θw from the standard value measured in other electroweak processes. The results are insensitive to different inputs. The light-flavor quark asymmetry of d¯–u¯ is also investigated and found to be consistent with the experimental measurements. Therefore the chiral quark model provides a successful picture to understand the NuTeV anomaly, as well as the light-flavor quark asymmetry and the proton spin problem in previous studies.