Dimuon Production by 0-600 GeV Neutrinos in the Fermilab 15ft. Bubble Chamber

Abstract

Neutrino (and anti-neutr1no) induced events with multi-muons in the final state are studied using the Femilab 15 Ft. Bubble Chamber. The neutrino beam is made by 800 GeV protons incident on a Beryllium target, and the secondaries are focused by a quadrupole triplet train tuned to 300 GeV/c. The bubble chamber, filled w1th a 74% molar Ne-H2 mix, has been equipped w1th a new External Muon Ident1fier/Internal Picket Fence system. 44 $\mu^-\mu^+$ (neutrino Induced), 8 $\mu^+\mu^-$ (anti- neutrino Induced), 11 $\mu^-\mu^-$, 1 $\mu^+\mu^+$, and O tri-muons are observed. After subtracting background and correcting for detection losses, the opposite sign rate (per charged current event) 1s 0.62 ± 0.13%, for $P_{\mu}$ ~ 4 GeV/c, the 11ke s1gn events are cons1stent w1th background, and the 90% conf1dence level upper 1imit for $\mu^-\mu^-/\mu^-$ is 1.1 * $10^{-3}$• Eight neutral strange particles are observed 1n the opposite sign sample, lead1ng to a corrected rate for $\mu\mu V^0 X/\mu\mu X$ of 0.50 ± 0.21. One neutral strange part1cle is observed in the 1ike-sign sample, and the raw neutral strange particle rate per 1ike-sign event is consistent with the raw rate in charged current events. We present kinematic distributions of the event samples, where the opposite s1gn sample is compared w1th the pred1ct1ons of a charm Monte Carlo and background pred1ct1ons, and the 1ike-sign event sample 1s compared w1th the pred1ct1ons of a background calculat1on.