Apparent CPT Violation in Neutrino Oscillation Experiments

TL;DR

This paper explores how light sterile neutrinos and new forces could mimic CPT violation in neutrino oscillation experiments, potentially explaining anomalies without actual CPT violation.

Contribution

It introduces a model with a sterile neutrino and B-L interaction that accounts for neutrino-antineutrino oscillation differences, fitting experimental data without true CPT violation.

Findings

Model improves fit to MINOS neutrino and antineutrino data

B-L interaction enhances neutrino-antineutrino differences

Parameter regions are consistent with experimental constraints

Abstract

We consider searching for light sterile fermions and new forces by using long baseline oscillations of neutrinos and antineutrinos. A new light sterile state and/or a new force can lead to apparent CPT violation in muon neutrino and antineutrino oscillations. As an example, we present an economical model of neutrino masses containing a sterile neutrino. The potential from the Standard Model neutral current gives rise to a difference between the disappearance probabilities of neutrinos and antineutrinos, when mixing with a light sterile neutrino is considered. The addition of a B-L interaction adds coherently to the neutrino current potential and increases the difference between neutrino and antineutrino disappearance. We find that this model can improve the fit to the results of MINOS for both neutrinos and antineutrinos, without any CPT violation, and that the regions of parameter space which improve the fit are within experimental constraints.