Strong constraints on neutrino nonstandard interactions from TeV-scale $\nu_\mu$ disappearance at IceCube

TL;DR

This study uses eight years of IceCube atmospheric neutrino data to place the most stringent constraints to date on nonstandard neutrino interactions, specifically on the parameter _{} with no significant evidence of NSI.

Contribution

The paper provides the strongest experimental constraints on neutrino nonstandard interactions from TeV-scale atmospheric neutrino observations.

Findings

Best-fit _{} consistent with no NSI (p=25.2%)

90% confidence interval _{} between -0.0041 and 0.0031

Constraints are the tightest from any oscillation channel to date

Abstract

We report a search for nonstandard neutrino interactions (NSI) using eight years of TeV-scale atmospheric muon neutrino data from the IceCube Neutrino Observatory. By reconstructing incident energies and zenith angles for atmospheric neutrino events, this analysis presents unified confidence intervals for the NSI parameter $\epsilon_{\mu \tau}$. The best-fit value is consistent with no NSI at a p-value of 25.2%. With a 90% confidence interval of $-0.0041 \leq \epsilon_{\mu \tau} \leq 0.0031$ along the real axis and similar strength in the complex plane, this result is the strongest constraint on any NSI parameter from any oscillation channel to date.