PT Journal
AU T2K Collaboration (Abe, Kea
   Cervera-Villanueva, A
   Escudero, L
   Gomez-Cadenas, JJ
   Hansen, C
   Monfregola, L
   Sorel, M
   Stamoulis, P
TI Indication of Electron Neutrino Appearance from an Accelerator-Produced Off-Axis Muon Neutrino Beam
SO Physical Review Letters
JI Phys. Rev. Lett.
PY 2011
BP 041801
EP 8pp
VL 107
IS 4
DI 10.1103/PhysRevLett.107.041801
LA English
AB The T2K experiment observes indications of nu(mu) -> nu(mu) e appearance in data accumulated with 1.43 x 10(20) protons on target. Six events pass all selection criteria at the far detector. In a three-flavor neutrino oscillation scenario with |Delta m(23)(2)| = 2.4 x 10(-3) eV(2), sin(2)2 theta(23) = 1 and sin(2)2 theta(13) = 0, the expected number of such events is 1.5 +/- 0.3(syst). Under this hypothesis, the probability to observe six or more candidate events is 7 x 10(-3), equivalent to 2.5 sigma significance. At 90% C.L., the data are consistent with 0.03(0.04) < sin(2)2 theta(13) < 0.28(0.34) for delta(CP) = 0 and a normal (inverted) hierarchy.
ER