Constraints On The sbar-s Asymmetry Of The Proton In Chiral Effective Theory

Abstract

We investigate the s −s asymmetry in the proton in chiral effective theory. Unlike previous meson cloud model calculations, which accounted for kaon loop contributions with on-shell intermediate states alone, this work includes off-shell terms and contact interactions, which impact the shape of the s −s difference. We use the hyperon production data and the latest results from global PDF fits to constrain the parameters within Pauli-Villars regularization procedure, which preserves chiral symmetry and Lorentz invariance. We also extract the correction to the NuTeV anomaly from strange asymmetry effect.