The relative absence of ν${\mathrm{¯}}_{\mathrm{\mu }}$-induced charged current events with respect to ${\nu }_{\mathrm{\mu }}$-induced events at large (>0.45) and large y (>0.70) enables us to limit the right handed coupling of the weak current. Our data restrict ‖η${\mathrm{\Vert }}^2$=‖${\mathit{g}}_{\mathit{R}}$/${\mathit{g}}_{\mathit{L}}$${\mathrm{\Vert }}^2$<0.0 015 with 90% C.L. Within the framework of left-right symmetric models, this measurement imposes a limit upon the mixing angle of the left and right handed bosons. Unlike the limits imposed by the μ-decay and nuclear β-decay experiments, our limit is valid irrespective of the mass of the right handed neutrino.

• Received 2 December 1991

DOI:https://doi.org/10.1103/PhysRevLett.68.3499