Comprehensive Analysis of Neutrinos in SK part II -- L/E Analysis for Single Ring Muon Events I --

TL;DR

This paper re-analyzes the L/E distribution of fully contained muon events in Super-Kamiokande, revealing that the original assumption about neutrino direction leads to a misinterpretation of the oscillation signal due to backscattering effects.

Contribution

It demonstrates that the L_mu/E_nu distribution does not accurately reflect the original neutrino oscillation pattern, challenging previous assumptions in Super-Kamiokande analyses.

Findings

L_mu/E_nu does not show the maximum oscillation.

Backscattering and azimuthal effects distort L/E measurements.

Original L_nu/E_nu distribution cannot be directly inferred.

Abstract

By referring to the procedures developed in the preceeding paper, we re-analyze the L/E distribution for Fully Contained Events resulting from quasi-elatic scattering (QEL) obtained from the Super-Kamiokande Experiment in relation to their assumption that the direction of the incident neutrino coincide with that of the produced leptons. As the result of it, we clarify that they do not measure L_nu/E_nu distribution itself, but L_mu/E_nu distribution, which cannot show the maximum oscillation existed in the original L_nu/E_nu distribution, because L_nu could not be approximated by L_mu due to the backscattering effect and the azimuthal angle effect in QEL.