Trimuon events observed in high-energy antineutrino interactions

Abstract Eight μ + μ + μ − events have been observed in the CDHS detector during the 330 GeV and 350 GeV antineutrino wide-band beam exposures at CERN. The corresponding average trimuon rate relative to the single-muon rate is (1.8 ± 0.6) × 10 −5 for visible energy ⩾ 30 GeV and muon momenta ⩾ 4.5 GeV c . Some characteristics of these antineutrino trimuon events are compared with μ − μ − μ + events produced by neutrinos.