# Search for sterile neutrino mixing using three years of IceCube DeepCore data

## TL;DR

This paper searches for light sterile neutrinos using three years of IceCube DeepCore atmospheric neutrino data, finding no evidence for their existence and setting limits on their mixing parameters.

## Contribution

It provides the first constraints on sterile neutrino mixing parameters using DeepCore atmospheric neutrino data in the 10-60 GeV range.

## Key findings

- No evidence of sterile neutrino mixing was observed.
- Limits set on the mixing matrix elements: |U_{μ4}|^2 < 0.11 and |U_{τ4}|^2 < 0.15.
- Results are consistent with the standard three-neutrino model.

## Abstract

We present a search for a light sterile neutrino using three years of atmospheric neutrino data from the DeepCore detector in the energy range of approximately $10-60~$GeV. DeepCore is the low-energy sub-array of the IceCube Neutrino Observatory. The standard three-neutrino paradigm can be probed by adding an additional light ($\Delta m_{41}^2 \sim 1 \mathrm{\ eV^2}$) sterile neutrino. Sterile neutrinos do not interact through the standard weak interaction, and therefore cannot be directly detected. However, their mixing with the three active neutrino states leaves an imprint on the standard atmospheric neutrino oscillations for energies below 100 GeV. A search for such mixing via muon neutrino disappearance is presented here. The data are found to be consistent with the standard three neutrino hypothesis. Therefore we derive limits on the mixing matrix elements at the level of $|U_{\mu4}|^2 < 0.11 $ and $|U_{\tau4}|^2 < 0.15 $ (90% C.L.) for the sterile neutrino mass splitting $\Delta m_{41}^2 = 1.0$ eV$^2$.