Document Type
Article
Publication Date
8-5-2013
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.
Publication Source (Journal or Book title)
Physical Review D - Particles, Fields, Gravitation and Cosmology
Recommended Citation
Abe, K., Abgrall, N., Aihara, H., Akiri, T., Albert, J., Andreopoulos, C., Aoki, S., Ariga, A., Ariga, T., Assylbekov, S., Autiero, D., Barbi, M., Barker, G., Barr, G., Bass, M., Batkiewicz, M., Bay, F., Bentham, S., Berardi, V., Berger, B., Berkman, S., Bertram, I., Beznosko, D., Bhadra, S., Blaszczyk, F., Blondel, A., Bojechko, C., & Boyd, S. (2013). Evidence of electron neutrino appearance in a muon neutrino beam. Physical Review D - Particles, Fields, Gravitation and Cosmology, 88 (3) https://doi.org/10.1103/PhysRevD.88.032002