Updated three-neutrino oscillation parameters from global fits

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1 Updated three-neutrino oscillation parameters from fits (Based on arxiv:14.74) Mariam Tórtola IFIC, Universitat de València/CSIC 37th International Conference on High Energy Physics 3th July 214, Valencia.

2 3-neutrino oscillation formalism Neutrino mixing is described by 3 mixing angles and 1 Dirac (+2 Majorana) CP phase: two possible mass orderings: neutrino oscillation probability

reactor: KamLAND, Double Chooz, RENO, Daya Bay -

3 Experimental data and methodology Data included - solar: Homestake, Gallex/GNO, SAGE, Borexino, SNO, Super-K - reactor: KamLAND, Double Chooz, RENO, Daya Bay - atmospheric: Super-K Parameter sensitivity - LBL: K2K, MINOS, T2K Methodology

4 Solar and atmospheric parameters m 2 21 [ - ev 2 ] ,99% CL KamLAND solar m 2 31 [ -3 ev 2 ] ,99% CL MINOS T2K ,99% CL MINOS T2K sin 2 θ 12 - θ 12 determined by solar data - Δm 2 21 dominated by KamLAND. - mismatch between Δm 2 21 from solar and KamLAND - θ 23 best constrained by T2K - Δm 2 31 dominated by MINOS - SK-atm data in agreement with LBL * T2K prefers maximal θ 23 * MINOS prefers non-maximal θ 23

5 Reactor mixing angle 3 DBay DBay 2 RENO RENO LBL.2.4 DCHOOZ LBL DCHOOZ The determination of θ 13 is totally dominated by Daya Bay

6 The octant of the atmospheric angle LBL + sol + KamLAND + SBL reactors + SK-atmosph.6 = 1,4,9 - Appearance probability at LBL:.4.2 P µe sin 2 (2θ 13 ) degeneracy in θ 13 -θ 23 plane reactor data fix θ 13 and break the degeneracy moving θ 23 to the 2nd octant. - SK-atm data do not change this tendency and θ 23 remains in the 2nd octant in fit

7 Sensitivity to the CP phase δ / π LBL glob LBL LBL mismatch between θ 13 value measured by reactors and preferred LBL-value for certain values of δ. significant rejection for values of δ.π emerges from the fit: disfavoured at 1.8σ (2.σ) for (). δ / π 1 glob best fit values:. = 1,4,9 LBL δ =( )π () δ =( )π ()

8 Update after Neutrino-214 Conference Double Chooz: days [arxiv: ] rate + shape analysis: sin 2 2θ 13 = % precision (36%) RENO: 8 days [talk by Seon-Hee Seo] rate-only analysis: sin 2 2θ 13 =.1 ±.8(stat) ±.(syst) 13% uncert. (18%) Daya Bay: 621 days of data (6AD + 8AD) [Talk by Chao Zhang] rate + shape analysis: sin 2 2θ 13 =.84 ±. 6% precision (9%) lower best fit value new reactor component at MeV observed in RENO (3.6σ) and Double Chooz (3.σ), correlated with reactor thermal power. origin of the excess? not very relevant for θ 13 measurement, based on Far/Near comparison

9 Impact of new data over the fit Before ν-214 θ 13 After ν-214 (arxiv:14.74) (this update) : =.23 ±.2 : =.24 ±.2 : = % -.9 % : = new Daya Bay data favour lower value of θ 13 and increase precision

10 Impact of new data over the fit θ 23 octant Before ν-214 After ν-214 (arxiv:14.74) (this update) : local minimum at 1st octant with Δχ 2 =.28 : 1st octant values allowed with Δχ 2 > 1. : local minimum at 1st octant with Δχ 2 =.71 : 1st octant values allowed with Δχ 2 > 2. lower θ 13 value favours slightly larger values of θ 23 (2nd octant)

11 Impact of new data over the fit δ phase Before ν-214 After ν-214 (arxiv:14.74) (this update) δ/π Best fit: δ 1.π for and : δ.π disfavoured at 1.8σ : δ.π disfavoured at 2.σ δ/π Best fit: δ 1.π for and : δ.π disfavoured at 2.2σ : δ.π disfavoured at 2.8σ lower θ 13 value increases the tension with LBL data, enhancing the rejection against δ.π

12 Updated fit summary 2.3% 2.4% sin 2 θ % 7.3% 6.8%.4%.2% m 2 21 [- ev 2 ] 2 2. m 2 31 [-3 ev 2 ] δ/π No indication for correct mass ordering: ( ) =.6

13 Summary Recent T2K data provide the most sensitive measurement of θ 23 Our fit shows a preference for θ 23 >π/4, although for a local minimum appears in =.47 with Δχ 2 =.71. For, solutions in the first octant appear only at 1.4σ θ 13 determination improved thanks to last results from reactor experiments, mainly Daya Bay An enhanced sensitivity to the CP violation phase emerges from the complementarity between accelerator and reactor data (increased after Neutrino-214) No sensitivity to neutrino mass hierarchy

Neutrino Physics II. Neutrino Phenomenology. Arcadi Santamaria. TAE 2014, Benasque, September 19, IFIC/Univ. València

Neutrino Physics II. Neutrino Phenomenology. Arcadi Santamaria. TAE 2014, Benasque, September 19, IFIC/Univ. València Neutrino Physics II Neutrino Phenomenology Arcadi Santamaria IFIC/Univ. València TAE 2014, Benasque, September 19, 2014 Neutrino Physics II Outline 1 Neutrino oscillations phenomenology Solar neutrinos