Study of high-energy neutrino neutral-current interactions

From an exposure of the Fermilab 15-foot bubble chamber to the Tevatron quadrupole triplet neutrino beam, we have determined the ratio of neutral-current (NC) to charged-current (CC) interactions to be 0.288{plus minus}0.032 for events with visible hadron momentum above 10 GeV/{ital c}. The mean {nu}({bar {nu}}) event energy is 150 (110) GeV, which is higher than that for any previous beam. This result agrees with those from previous experiments at lower energies. The NC/CC ratio is derived for a combined sample of {nu} and {bar {nu}} events. A value of 0.274{plus minus}0.038 is obtained for the dominant {nu} component assuming {bar {nu}} NC/CC=0.39{plus minus}0.08. For events with visible hadron momentum above 25 GeV/{ital c}, where the neutral hadron contamination remaining in the NC sample is assumed to be negligible, the combined NC/CC is 0.323{plus minus}0.025 and the {ital K}{sup 0} production rates are 0.375{plus minus}0.064 per CC and 0.322{plus minus}0.073 per NC event. The corresponding {Lambda} rates are 0.161{plus minus}0.030 per CC and 0.113{plus minus}0.030 per NC event. The {ital K}{sup 0} and {Lambda} distributions of the fractional hadron energy variable {ital z} in NC events are consistent with those in CC events.