A Measurement of Atmospheric Neutrino Oscillation Parameters by Super-Kamiokande I

TL;DR

This paper reports a comprehensive analysis of atmospheric neutrino data from Super-Kamiokande I, confirming neutrino oscillations with precise parameter constraints across a wide energy range.

Contribution

It provides the first combined analysis of multiple neutrino data samples from Super-Kamiokande I, significantly refining oscillation parameter measurements.

Findings

Neutrino oscillations are confirmed with high confidence.

Oscillation parameters are constrained to specific ranges.

Data covers neutrino energies from 100 MeV to 10 TeV.

Abstract

We present a combined analysis of fully-contained, partially-contained and upward-going muon atmospheric neutrino data from a 1489 day exposure of the Super--Kamiokande detector. The data samples span roughly five decades in neutrino energy, from 100 MeV to 10 TeV. A detailed Monte Carlo comparison is described and presented. The data is fit to the Monte Carlo expectation, and is found to be consistent with neutrino oscillations of $\nu_\mu \leftrightarrow \nu_\tau$ with $\sin^22\theta > 0.92$ and $1.5\times 10^{-3} < \Delta m^2 < 3.4\times 10^{-3}{\rm eV}^2$ at 90% confidence level.