Indication of Electron Neutrino Appearance from an Accelerator-produced Off-axis Muon Neutrino Beam

7月 21, 2011

The T2K experiment observes indications of νμ → νe appearance in data accumulated with 1.43×1020 protons on target. Six events pass all selection criteria at the far detector. In a three-flavor neutrino oscillation scenario with Δm223 = 2.4×10-3 eV2, sin2(2θ23) = 1 and sin2(2θ13) = 0, the expected number of such events is 1.5±0.3(syst.).