Michel Gonin – Ecole Polytechnique – France

1987 : SUPER NOVA SN1987A Super-Kamiokande Introduction neutrino oscillations mixing matrices Introduction neutrino oscillations mixing matrices

26 free parameters including 8 for neutrinos electron neutrino

c = cos s = sin ? ≈ The last mixing angle  13 was missing before 2012 The complex phase δ is still unknow The last mixing angle  13 was missing before 2012 The complex phase δ is still unknow

Measurements of the matrix elements θ 12 = 33.6 ◦ ± 1.0 ◦ θ 23 = 45 ◦ ± 6 ◦

CP violation δ  0 " for the discovery of the origin of the broken symmetry which predicts the existence of at least three families of quarks in nature".  3 generations of particles  3 mixing angles, all different from zero.  masse states  flavor states

World (new) baseline oscillation experiments

beam  beam  Intense beam  Near detectors  Huge far detector

sin 2 2    disappearance  m 23 2 sin 2 2   e appearance T2K main physics goals Probe ν μ to ν e oscillations with sensitivity improvement Precise measurement of the “atmospheric” parameters  23,  m 32 2

How do we detect neutrinos ? Neutrino interaction with some unrelated muon (“rock muon”) Charge current quasi elastic neutrino interaction n  p  e  e n  p  e  e e  n  p  e e  n  p  e n  p  e  e n  p  e  e e  n  p  e e  n  p  e   n  p     n  p  

Feb. 3, 2009 Target Station

Feb. 3, 2009 HornsHorns

16 Inside the decay tunnel

Non accelerator experiments (reactor)

Exclusion for non zero - number of  sin 2 (2  13 sin 2 (2  13 ) “appearance” θ 13 = 9.1 ◦ ± 0.6 ◦

e appearance e appearance Discovery of neutrino appearance in flavor oscillations New results

e disappearance e disappearance

New results 2013

First indication for strong CP violation in the lepton sector ? New results 2013

NOVA CP phase δ Perspectives Perspectives

 Is CP violated “strongly” in neutrino oscillation ?  Is the source of the violation due to complex phase associated with 3 generations ?  Only 3 generations for leptons ? Sterile neutrinos ?  Unitary triangle and physics beyond the standard model

 High power accelerator and huge detector needed  Asymmetry of neutrino and anti-neutrino induced by interaction in matter is large

Measurement of  13 C=cos S=sin

Merci beaucoup Joe !