Strange and Anti-strange Sea Distributions from Neutrino-Nucleon Deep Inelastic Scattering

We perform QCD fit of the nucleon strange and anti-strange sea distributions to the neutrino and anti-neutrino dimuon data by the CCFR and NuTeV collaborations, supplemented by the inclusive charged lepton-nucleon Deep Inelastic Scattering (DIS) and Drell-Yan data. The effective semi-leptonic charmed-hadron branching ratio is constrained from the inclusive charmed hadron measurements performed by the FNAL-E531 and CHORUS neutrino emulsion experiments as $B_{\mu }=(8.8\pm 0.5)$. We obtain a strange sea suppression factor {$\kappa (20{\mathrm{G}\mathrm{e}\mathrm{V}}^2)=0.62\pm 0.04(\mathrm{e}\mathrm{x}\mathrm{p}\mathrm{.})\pm 0.03(\mathrm{Q}\mathrm{C}\mathrm{D})$}. An $x$-distribution of total strange sea obtained in the fit is slightly softer than the non-strange sea, and an asymmetry between strange and anti-strange quark distributions is consistent with zero (integrated over $x$ it is equal to {$0.0013\pm 0.0009(\mathrm{e}\mathrm{x}\mathrm{p}\mathrm{.})\pm 0.0002(\mathrm{Q}\mathrm{C}\mathrm{D})$ at the scale of $20 {\rm GeV^2}$}).