A Measurement of the Tau Neutrino Cross Section in Atmospheric Neutrino Oscillations with Super-Kamiokande

Understand

Using 5,326 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$\pm$0.32 under the assumption of normal neutrino hierarchy, relative to the expectation of unity with neutrino oscillation.
• The result excludes the hypothesis of no-tau-appearance with a significance level of 4.6$\sigma$.
• The inclusive charged-current tau neutrino cross section averaged by the tau neutrino flux at Super-Kamiokande is measured to be $(0.94\pm0.20)\times 10^{-38}$ cm$^{2}$.