Using 5326 days of atmospheric neutrino data, a search for atmospheric tau neutrino appearance has
been performed in the Super-Kamiokande experiment. Super-Kamiokande measures the tau normalization
to be 1.47 ± 0.32 under the assumption of normal neutrino hierarchy, relative to the expectation of unity
with neutrino oscillation. The result excludes the hypothesis of no-tau appearance with a significance level
of 4.6σ. The inclusive charged-current tau neutrino cross section averaged by the tau neutrino flux at SuperKamiokande
is measured to be ð0.94 ± 0.20Þ × 10−38 cm2. The measurement is consistent with the
Standard Model prediction, agreeing to within 1.5σ