The T2K experiment measures muon neutrino disappearance and electron neutrino appearance in accelerator-produced neutrino and antineutrino beams. With an exposure of $14.7(7.6)times 10^{20}$ protons on target in neutrino (antineutrino) mode, 89 $ u_e$ candidates and 7 anti-$ u_e$ candidates were observed while 67.5 and 9.0 are expected for $delta_{CP}=0$ and normal mass ordering. The obtained $2sigma$ confidence interval for the $CP$ violating phase, $delta_{CP}$, does not include the $CP$-conserving cases ($delta_{CP}=0,pi$). The best-fit values of other parameters are $sin^2theta_{23} = 0.526^{+0.032}_{-0.036}$ and $Delta m^2_{32}=2.463^{+0.071}_{-0.070}times10^{-3} mathrm{eV}^2/c^4$.
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