Measurement of neutrino and antineutrino oscillations by the T2K experiment including a new additional sample of ve interactions at the far detector

Authors

K. Abe, The University of Tokyo
J. Amey, Imperial College London
C. Andreopoulos, University of Liverpool
M. Antonova, Institute for Nuclear Research of the Russian Academy of Sciences
S. Aoki, Kobe University
A. Ariga, University of Bern
Y. Ashida, Kyoto University
S. Ban, Kyoto University
M. Barbi, University of Regina
G. J. Barker, University of Warwick
G. Barr, University of Oxford
C. Barry, University of Liverpool
M. Batkiewicz, Henryk Niewodniczanski Institute of Nuclear Physics of the Polish Academy of Sciences
V. Berardi, Politecnico di Bari
S. Berkman, The University of British Columbia
S. Bhadra, York University
S. Bienstock, Université de Paris
A. Blondel, Université de Genève
S. Bolognesi, Institut de Recherche sur les Lois Fondamentales de l'Univers
S. Bordoni, Institut de Física d'Altes Energies, Bellaterra
S. B. Boyd, University of Warwick
D. Brailsford, Lancaster University
A. Bravar, Université de Genève
C. Bronner, The University of Tokyo
M. Buizza Avanzini, Laboratoire Leprince-Ringuet
R. G. Calland, The University of Tokyo
T. Campbell, Colorado State University
S. Cao, High Energy Accelerator Research Organization, Tsukuba

Document Type

Article

Publication Date

11-1-2017

Abstract

The T2K experiment reports an updated analysis of neutrino and antineutrino oscillations in appearance and disappearance channels. Asample of electron neutrino candidates at Super-Kamiokande in which a pion decay has been tagged is added to the four single-ring samples used in previous T2K oscillation analyses. Through combined analyses of these five samples, simultaneous measurements of four oscillation parameters, j?m2 32j, sin2 ?23, sin2 ?13, and dCP and of the mass ordering are made. A set of studies of simulated data indicates that the sensitivity to the oscillation parameters is not limited by neutrino interaction model uncertainty. Multiple oscillation analyses are performed, and frequentist and Bayesian intervals are presented for combinations of the oscillation parameters with and without the inclusion of reactor constraints on sin2 ?13.When combined with reactor measurements, the hypothesis of CP conservation (dCP 0 or p) is excluded at 90% confidence level. The 90% confidence region for dCP is -2.95;-0.44(-1.47;-1.27) for normal (inverted) ordering. The central values and 68% confidence intervals for the other oscillation parameters for normal (inverted) ordering are ?m2 32 2.540.082.510.08 10-3 eV2=c4 and sin2?23 0.55+0.05 -0.09 (0.55+0.05 -0.08 ), compatible with maximal mixing. In the Bayesian analysis, the data weakly prefer normal ordering (Bayes factor 3.7) and the upper octant for sin2 ?23 (Bayes factor 2.4).

Publication Source (Journal or Book title)

Physical Review D

Recommended Citation

Abe, K., Amey, J., Andreopoulos, C., Antonova, M., Aoki, S., Ariga, A., Ashida, Y., Ban, S., Barbi, M., Barker, G., Barr, G., Barry, C., Batkiewicz, M., Berardi, V., Berkman, S., Bhadra, S., Bienstock, S., Blondel, A., Bolognesi, S., Bordoni, S., Boyd, S., Brailsford, D., Bravar, A., Bronner, C., Buizza Avanzini, M., Calland, R., Campbell, T., & Cao, S. (2017). Measurement of neutrino and antineutrino oscillations by the T2K experiment including a new additional sample of ve interactions at the far detector. Physical Review D, 96 (9) https://doi.org/10.1103/PhysRevD.96.092006