Combined Analysis of Neutrino and Antineutrino Oscillations at T2K

T2K reports its first results in the search for CP violation in neutrino oscillations using appearance and disappearance channels for neutrino- and antineutrino-mode beams. The data include all runs from January 2010 to May 2016 and comprise 7.482×10²⁰ protons on target in neutrino mode, which yielded in the far detector 32 e-like and 135 μ-like events, and 7.471×10²⁰ protons on target in antineutrino mode, which yielded 4 e-like and 66 μ-like events. Reactor measurements of sin²2θ₁₃ have been used as an additional constraint. The one-dimensional confidence interval at 90% for the phase δCP spans the range (-3.13, -0.39) for normal mass ordering. The CP conservation hypothesis (δCP=0, π) is excluded at 90% C.L.