Measurement of the Neutrino Mixing Angle theta(23) in NOvA

作者：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

来源：Physical Review Letters, 2017, 118(15): 151802.

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 x 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 theta(23) mixing (theta(23) = pi/4). Assuming the normal mass hierarchy, we find Delta m(32)(2) = (2.67 +/- 0.11) x 10(-3) eV(2) and sin(2) theta(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 2.6 sigma significance.

• 出版日期2017-4-10