Test of Lorentz and CPT violation with Short Baseline Neutrino Oscillation Excesses

TL;DR

This study tests for Lorentz and CPT violation in neutrino oscillations using MiniBooNE data, finding no significant sidereal variation and setting stringent limits on SME coefficients.

Contribution

It provides the first limits on SME coefficients for neutrino oscillations using MiniBooNE data and analyzes sidereal time dependence in neutrino appearance.

Findings

No significant sidereal variation detected in neutrino data.

Sets limits of order 10E-20 GeV on SME coefficients.

Provides best limits on certain SME coefficients for neutrino oscillations.

Abstract

The sidereal time dependence of MiniBooNE electron neutrino and anti-electron neutrino appearance data are analyzed to search for evidence of Lorentz and CPT violation. An unbinned Kolmogorov-Smirnov test shows both the electron neutrino and anti-electron neutrino appearance data are compatible with the null sidereal variation hypothesis to more than 5%. Using an unbinned likelihood fit with a Lorentz-violating oscillation model derived from the Standard Model Extension (SME) to describe any excess events over background, we find that the electron neutrino appearance data prefer a sidereal time-independent solution, and the anti-electron neutrino appearance data slightly prefer a sidereal time-dependent solution. Limits of order 10E-20 GeV are placed on combinations of SME coefficients. These limits give the best limits on certain SME coefficients for muon neutrino to electron neutrino and anti-muon neutrino to anti-electron neutrino oscillations. The fit values and limits of combinations of SME coefficients are provided.