Strange sea asymmetry in nucleons

Abstract

We evaluate the medium effects in nucleon which can induce an asymmetry of the strange sea. The short-distance effects determined by the weak interaction can give rise to $δm\equiv Δm_s-Δm_{\bar s}$ where $Δm_{s(\bar s)}$ is the medium-induced mass of strange quark by a few KeV at most, but the long-distance effects by strong interaction could be sizable.