Brief notes on neutrino oscillations and latest T2K results Pablo - PowerPoint PPT Presentation

Brief notes on neutrino oscillations and latest T2K results Pablo Fernández de Salas Oskar Klein Centre for Cosmoparticle Physics, Stockholm University BSM meeting - 28th April 2020

Two distinct oscillation frequencies 3 neutrino oscillation probability (vacuum) 2 neutrino approximation Oscillation parameters from best-fit values of P.F. de Salas et al, PLB 782 (2018) 633 28th April 2019 P. F. de Salas 2

Experiments and neutrino parameters Different experiments are sensitive to different parameters atmospheric angle reactor angle solar angle CP phase 28th April 2019 P. F. de Salas 3

Experiments and neutrino parameters LBL experiments such as T2K Disappearance probability Appearance probability Jarlskog invariant 28th April 2019 P. F. de Salas 4

T2K (Tokai to Kamioka) Image from: https://www.ppd.stfc.ac.uk/Pages/T2K.aspx <E> = 0.6 GeV Image from: Khabibullin, Marat. (2018). Recent results from the T2K experiment. EPJ Web of Conferences. 191. 03001 28th April 2019 P. F. de Salas 5

Neutrino fmavour in Super-Kamiokande Number of events ν ν 80 and CC T2K Data e e ν ν and CC Neutral current µ µ 60 40 ν ν -like -like µ e 20 Super-Kamiokande interior 0 -2000 -1000 0 1000 2000 µ e/ PID discriminator K. Abe et al, Nature (2020) 580, 339 [arXiv:1910.03887} 28th April 2019 P. F. de Salas 6

Efgect of CP phase in event distribution K. Abe et al, Nature (2020) 580, 339 [arXiv:1910.03887} 28th April 2019 P. F. de Salas 7

T2K (Tokai to Kamioka) K. Abe et al, Nature (2020) 580, 339 [arXiv:1910.03887} 28th April 2019 P. F. de Salas 8

Experiments and neutrino parameters Solar sector Atmospheric neutrino detectors Cl, Ga SK, SNO SK (official χ² maps) Borexino IceCube-DeepCore KamLAND ANTARES LBL accelerator SBL reactor MINOS Daya Bay K2K, T2K RENO NOνBA Double Chooz P.F. de Salas et al, PLB 782 (2018) 633 28th April 2019 P. F. de Salas 9

Summary global fjt ~2.6% Relative 1 sigma uncertainties ~1.5% ~6.3% ~5.5% ~3.5% P.F. de Salas et al, PLB ~13.5% 782 (2018) 633 28th April 2019 P. F. de Salas 10

The CP phase ● Leading experiment T2K ● Global sensitivity improved thanks to reactor angle determination ● Values ~π/2!π/2 disfavoured at > 4 σ P.F. de Salas et al, PLB 782 (2018) 633 28th April 2019 P. F. de Salas 11