Measurement of the Neutrino Mixing Angle θ_{23} in NOvA

• Published in: Physical review letters Vol. 118; no. 15; p. 151802
• Main Authors: Adamson, P, Aliaga, L, Ambrose, D, Anfimov, N, Antoshkin, A, Arrieta-Diaz, E, Augsten, K, Aurisano, A, Backhouse, C, Baird, M, Bambah, B A, Bays, K, Behera, B, Bending, S, Bernstein, R, Bhatnagar, V, Bhuyan, B, Bian, J, Blackburn, T, Bolshakova, A, Bromberg, C, Brown, J, Brunetti, G, Buchanan, N, Butkevich, A, Bychkov, V, Campbell, M, Catano-Mur, E, Childress, S, Choudhary, B C, Chowdhury, B, Coan, T E, Coelho, J A B, Colo, M, Cooper, J, Corwin, L, Cremonesi, L, Cronin-Hennessy, D, Davies, G S, Davies, J P, Derwent, P F, Desai, S, Dharmapalan, R, Ding, P, Djurcic, Z, Dukes, E C, Duyang, H, Edayath, S, Ehrlich, R, Feldman, G J, Frank, M J, Gabrielyan, M, Gallagher, H R, Germani, S, Ghosh, T, Giri, A, Gomes, R A, Goodman, M C, Grichine, V, Group, R, Grover, D, Guo, B, Habig, A, Hartnell, J, Hatcher, R, Hatzikoutelis, A, Heller, K, Himmel, A, Holin, A, Hylen, J, Jediny, F, Judah, M, Kafka, G K, Kalra, D, Kasahara, S M S, Kasetti, S, Keloth, R, Kolupaeva, L, Kotelnikov, S, Kourbanis, I, Kreymer, A, Kumar, A, Kurbanov, S, Lang, K, Lee, W M, Lin, S, Liu, J, Lokajicek, M, Lozier, J, Luchuk, S, Maan, K, Magill, S, Mann, W A, Marshak, M L, Matera, K, Matveev, V, Méndez, D P, Messier, M D, Meyer, H, Miao, T
• Format: Journal Article
• Language: English
• Published: United States 14.04.2017
• ISSN: 1079-7114
• DOI: 10.1103/PhysRevLett.118.151802

This Letter reports new results on muon neutrino disappearance from NOvA, using a 14 kton detector equivalent exposure of 6.05×10^{20} protons on target from the NuMI beam at the Fermi National Accelerator Laboratory. The measurement probes the muon-tau symmetry hypothesis that requires maximal θ_{23} mixing (θ_{23}=π/4). Assuming the normal mass hierarchy, we find Δm_{32}^{2}=(2.67±0.11)×10^{-3}  eV^{2} and sin^{2}θ_{23} at the two statistically degenerate values 0.404_{-0.022}^{+0.030} and 0.624_{-0.030}^{+0.022}, both at the 68% confidence level. Our data disfavor the maximal mixing scenario with 2.6σ significance.