1. Evidence of electron neutrino appearance in a muon neutrino beam
- Author
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Abe, K, Abgrall, N, Aihara, H, Akiri, T, Albert, JB, Andreopoulos, C, Aoki, S, Ariga, A, Ariga, T, Assylbekov, S, Autiero, D, Barbi, M, Barker, GJ, Barr, G, Bass, M, Batkiewicz, M, Bay, F, Bentham, SW, Berardi, V, Berger, BE, Berkman, S, Bertram, I, Beznosko, D, Bhadra, S, Blaszczyk, FDM, Blondel, A, Bojechko, C, Boyd, S, Brailsford, D, Bravar, A, Bronner, C, Brook-Roberge, DG, Buchanan, N, Calland, RG, Caravaca Rodríguez, J, Cartwright, SL, Castillo, R, Catanesi, MG, Cervera, A, Cherdack, D, Christodoulou, G, Clifton, A, Coleman, J, Coleman, SJ, Collazuol, G, Connolly, K, Cremonesi, L, Curioni, A, Dabrowska, A, Danko, I, Das, R, Davis, S, Day, M, De André, JPAM, De Perio, P, De Rosa, G, Dealtry, T, Dennis, S, Densham, C, Di Lodovico, F, Di Luise, S, Dobson, J, Drapier, O, Duboyski, T, Dufour, F, Dumarchez, J, Dytman, S, Dziewiecki, M, Dziomba, M, Emery, S, Ereditato, A, Escudero, L, Finch, AJ, Frank, E, Friend, M, Fujii, Y, Fukuda, Y, Furmanski, A, Galymov, V, Gaudin, A, Giffin, S, Giganti, C, Gilje, K, Golan, T, Gomez-Cadenas, JJ, Gonin, M, Grant, N, Gudin, D, Hadley, DR, Haesler, A, Haigh, MD, Hamilton, P, Hansen, D, Hara, T, Hartz, M, Hasegawa, T, Hastings, NC, Hayato, Y, Hearty, C, and Helmer, RL
- Subjects
hep-ex ,Nuclear & Particles Physics ,Astronomical and Space Sciences ,Atomic ,Molecular ,Nuclear ,Particle and Plasma Physics ,Quantum Physics ,Atomic ,Molecular ,Nuclear ,Particle and Plasma Physics - Abstract
The T2K Collaboration reports evidence for electron neutrino appearance at the atmospheric mass splitting, |Δm322|≈2.4×10-3 eV2. An excess of electron neutrino interactions over background is observed from a muon neutrino beam with a peak energy of 0.6 GeV at the Super-Kamiokande (SK) detector 295 km from the beam's origin. Signal and background predictions are constrained by data from near detectors located 280 m from the neutrino production target. We observe 11 electron neutrino candidate events at the SK detector when a background of 3.3±0.4(syst) events is expected. The background-only hypothesis is rejected with a p value of 0.0009 (3.1σ), and a fit assuming νμ→νe oscillations with sinâ¡22θ23=1, δCP=0 and |Δm322|=2.4×10-3 eV2 yields sinâ¡22θ13=0.088-0.039+0. 049(stat+syst). © 2013 American Physical Society.
- Published
- 2013