Measurement of interference betweenWandZexchange in electron-neutrino electron scattering

Abstract

A measurement of the reaction ${\nu }_{\mathit{e}}$+${\mathit{e}}^{\mathrm{-}}$→${\nu }_{\mathit{e}}$+${\mathit{e}}^{\mathrm{-}}$ was performed using a beam-stop source of ${\nu }_{\mathit{e}}$. Based upon 234±35 events, we obtain a cross section of σ(${\nu }_{\mathit{e}}$e)=[9.9±1.5(stat)±1.0(syst)]×${10}^{\mathrm{-}42}$ ${\mathrm{cm}}^2$ ×[${\mathit{E}}_{\nu }$ (GeV)]. This reaction is mediated by the exchange of W and Z bosons and is thus sensitive to the interference between them. This interference is measured to be -1.07±0.17(stat)±0.11(syst), consistent with the destructive interference (-1.08) predicted by the standard model.