STUDY OF HIGH-ENERGY NEUTRINO NEUTRAL-CURRENT INTERACTIONS

From an exposure of the Fermilab 15-foot bubble chamber to the Tevatro n quadrupole triplet neutrino beam, we have determined the ratio of ne utral-current (NC) to charged-current (CC) interactions to be 0.288 +/ - 0.032 for events with visible hadron momentum above 10 GeV/c. The me an nu (nuBAR) event energy is 150 (110) GeV, which is higher than that for any previous beam. This result agrees with those from previous ex periments at lower energies. The NC/CC ratio is derived for a combined sample of nu and nuBAR events. A value of 0.274 +/- 0.038 is obtained for the dominant nu-component assuming nuBAR NC/CC = 0.39 +/- 0.08. F or events with visible hadron momentum above 25 GeV/c, where the neutr al hadron contamination remaining in the NC sample is assumed to be ne gligible, the combined NC/CC is 0.323 +/- 0.025 and the K0 production rates are 0.375 +/- 0.064 per CC and 0.322 +/- 0.073 per NC event. The corresponding LAMBDA-rates are 0.161 +/- 0.030 per CC and 0.113 +/- 0 .030 per NC event. The K0 and LAMBDA-distributions of the fractional h adron energy variable z in NC events are consistent with those in CC e vents.