Constraints on the non-standard interaction in propagation from atmospheric neutrinos

TL;DR

This paper investigates how atmospheric neutrino experiments can constrain non-standard flavor-dependent interactions during neutrino propagation, providing current and future bounds on relevant parameters using Superkamiokande and Hyperkamiokande data.

Contribution

It offers the first detailed analysis of atmospheric neutrino data constraining specific non-standard interaction parameters, including projections for future experiments.

Findings

Superkamiokande constrains | aneta| extless 0.8 at 2.5σ

Hyperkamiokande will improve constraints to | aneta| extless 0.3

Future analyses will tighten bounds on \\epsilon_{ee} and |\\\\epsilon_{e\\\tau}|

Abstract

The sensitivity of the atmospheric neutrino experiments to the non-standard flavor-dependent interaction in neutrino propagation is studied under the assumption that the only nonvanishing components of the non-standard matter effect are the electron and tau neutrino components $\epsilon_{ee}$, $\epsilon_{e\tau}$, $\epsilon_{\tau\tau}$ and that the tau-tau component satisfies the constraint $\epsilon_{\tau\tau}=|\epsilon_{e\tau}|^2/(1+\epsilon_{ee})$ which is suggested from the high energy behavior for atmospheric neutrino data. It is shown that the Superkamiokande (SK) data for 4438 days constrains $|\tan\beta|\equiv|\epsilon_{e\tau}/(1+\epsilon_{ee})|\lesssim 0.8$ at 2.5$\sigma$ (98.8\%) CL whereas the future Hyperkamiokande experiment for the same period of time as SK will constrain as $|\tan\beta|\lesssim 0.3$ at 2.5$\sigma$CL from the energy rate analysis and the energy spectrum analysis will give even tighter bounds on $\epsilon_{ee}$ and $|\epsilon_{e\tau}|$.