Measurement of Atmospheric Neutrino Oscillations with the ANTARES Neutrino Telescope

TL;DR

This paper reports on the measurement of atmospheric neutrino oscillation parameters using data from the ANTARES telescope, confirming results consistent with global averages and demonstrating the detector's capability to analyze neutrino oscillations at energies as low as 20 GeV.

Contribution

First measurement of atmospheric neutrino oscillation parameters using the ANTARES neutrino telescope data from 2007-2010.

Findings

Measured mass difference Δm_{32}^2 = (3.1 ± 0.9) × 10^{-3} eV^2

Confirmed oscillation suppression of vertical upgoing muon neutrinos

Demonstrated ANTARES' capability to analyze neutrino oscillations at energies down to 20 GeV

Abstract

The data taken with the ANTARES neutrino telescope from 2007 to 2010, a total live time of 863 days, are used to measure the oscillation parameters of atmospheric neutrinos. Muon tracks are reconstructed with energies as low as 20 GeV. Neutrino oscillations will cause a suppression of vertical upgoing muon neutrinos of such energies crossing the Earth. The parameters determining the oscillation of atmospheric neutrinos are extracted by fitting the event rate as a function of the ratio of the estimated neutrino energy and reconstructed flight path through the Earth. Measurement contours of the oscillation parameters in a two-flavour approximation are derived. Assuming maximum mixing, a mass difference of $\Delta m_{32}^2=(3.1\pm 0.9)\cdot 10^{-3}$ eV$^2$ is obtained, in good agreement with the world average value.