On the Interpretation of the Atmospheric Neutrino Data in Terms of Flavor Changing Neutrino Interactions

TL;DR

This paper analyzes Super-Kamiokande atmospheric neutrino data to evaluate flavor-changing neutrino interactions as a solution, finding that such interactions can fit the data within certain bounds.

Contribution

It provides a comprehensive analysis of recent atmospheric neutrino data considering flavor-changing interactions, quantifying their possible strength and viability.

Findings

FC interactions can describe the data with acceptable fit

The level of FC interactions is constrained to 10-50% of maximal

The analysis includes zenith angle and energy-dependent data

Abstract

Flavour changing (FC) neutrino-matter interactions have been proposed as a solution to the atmospheric neutrino anomaly. Here we perform the analysis of the full set of the recent 52 kTy Super-Kamiokande atmospheric neutrino data, including the zenith angle distribution of the contained events as well as the higher energy upward-going stopping and through-going muon events. Our results show that the FC mechanism can describe the full data sample with a chi^2_{min}=44/(33 d.o.f) which is acceptable at the 90% confidence level. The combined analysis confines the amount of FC to be either close to maximal or to the level of about (10-50)%.