Neutral Current Coupling-constants From Neutrino-electron Scattering

We are reporting on a determination of neutral current coupling constants from a study of differential cross sections of muon-(anti)neutrino electron scattering. The results were obtained with the CHARM-II detector which was exposed to the CERN wide band neutrino beam in the years 1987 to 1991. A total of about 3000 ve and 3000 v e scattering events were observed. We present a preliminary value of sin2φw determined with the ratio of neutrino and antineutrino electron scattering cross-sections, based on the full data sample, and we give a determination of the effective vector and axial-vector neutral current coupling constants and the first measurement of the shape of the y-distributions based on 80% of the total statistics.