Measurement of the atmospheric $\nu_e$ and $\nu_\mu$ energy spectra with the ANTARES neutrino telescope

TL;DR

This study measures the energy spectra of atmospheric electron and muon neutrinos between 100 GeV and 50 TeV using the ANTARES telescope over a decade, providing new insights beyond previous polar ice and Super-Kamiokande results.

Contribution

It presents the first combined measurement of atmospheric $ u_e$ and $ u_$ spectra with ANTARES, extending energy range and improving background suppression techniques.

Findings

Energy spectra consistent with previous measurements at high energies.

Effective suppression of atmospheric muon contamination.

Extended energy range for atmospheric neutrino measurements.

Abstract

This letter presents a combined measurement of the energy spectra of atmospheric $\nu_e$ and $\nu_\mu$ in the energy range between $\sim$100 GeV and $\sim$50 TeV with the ANTARES neutrino telescope. The analysis uses 3012 days of detector livetime in the period 2007--2017, and selects 1016 neutrinos interacting in (or close to) the instrumented volume of the detector, yielding shower-like events (mainly from $\nu_e+\overline \nu_e$ charged current plus all neutrino neutral current interactions) and starting track events (mainly from $\nu_\mu + \overline \nu_\mu$ charged current interactions). The contamination by atmospheric muons in the final sample is suppressed at the level of a few per mill by different steps in the selection analysis, including a Boosted Decision Tree classifier. The distribution of reconstructed events is unfolded in terms of electron and muon neutrino fluxes. The derived energy spectra are compared with previous measurements that, above 100 GeV, are limited to experiments in polar ice and, for $\nu_\mu$, to Super-Kamiokande.