Searching for eV-scale sterile neutrinos with eight years of atmospheric neutrinos at the IceCube neutrino telescope

TL;DR

This study uses eight years of atmospheric neutrino data from IceCube to search for eV-scale sterile neutrinos, setting constraints on their properties and finding no significant evidence for their existence.

Contribution

First detailed analysis of atmospheric neutrino data from IceCube targeting eV-scale sterile neutrinos within a 3+1 model, including systematic uncertainties and confidence interval construction.

Findings

No strong evidence for sterile neutrinos was observed.

Best-fit likelihood is consistent with the no sterile neutrino hypothesis.

Constraints on sterile neutrino parameters were established.

Abstract

We report in detail on searches for eV-scale sterile neutrinos, in the context of a 3+1 model, using eight years of data from the IceCube neutrino telescope. By analyzing the reconstructed energies and zenith angles of 305,735 atmospheric $\nu_\mu$ and $\bar{\nu}_\mu$ events we construct confidence intervals in two analysis spaces: $\sin^2 (2\theta_{24})$ vs. $\Delta m^2_{41}$ under the conservative assumption $\theta_{34}=0$; and $\sin^2(2\theta_{24})$ vs. $\sin^2 (2\theta_{34})$ given sufficiently large $\Delta m^2_{41}$ that fast oscillation features are unresolvable. Detailed discussions of the event selection, systematic uncertainties, and fitting procedures are presented. No strong evidence for sterile neutrinos is found, and the best-fit likelihood is consistent with the no sterile neutrino hypothesis with a p-value of 8\% in the first analysis space and 19\% in the second.