# Search for light sterile neutrinos with the T2K far detector Super-Kamiokande at a baseline of 295 km

## TL;DR

This study searches for light sterile neutrinos using T2K data, finding no evidence of mixing but setting the most stringent limits on sterile oscillation parameters for certain mass splittings.

## Contribution

First search for light sterile neutrinos with T2K data, providing the most stringent limits on sterile mixing for specific mass splittings.

## Key findings

- No evidence of sterile neutrino mixing was observed.
- Set the most stringent limits on $ heta_{24}$ for $ riangle m^2_{41}<3 imes 10^{-3}$ eV$^2$.
- Utilized neutral current and charged-current samples to enhance sensitivity.

## Abstract

We perform a search for light sterile neutrinos using the data from the T2K far detector at a baseline of 295 km, with an exposure of 14.7 (7.6)$\times 10^{20}$ protons on target in neutrino (antineutrino) mode. A selection of neutral current interaction samples are also used to enhance the sensitivity to sterile mixing. No evidence of sterile neutrino mixing in the 3+1 model was found from a simultaneous fit to the charged-current muon, electron and neutral current neutrino samples. We set the most stringent limit on the sterile oscillation amplitude $\sin^2\theta_{24}$ for the sterile neutrino mass splitting $\Delta m^2_{41}<3\times 10^{-3}$ eV$^2/c^4$.