Testing Lorentz Symmetry with the Double Chooz Experiment

TL;DR

This paper uses the Double Chooz reactor experiment data to search for Lorentz invariance violation in neutrino oscillations, setting new limits on SME coefficients, including first constraints in the e-tau sector.

Contribution

It is the first to analyze reactor neutrino data for Lorentz violation within the SME framework, providing new bounds on relevant coefficients.

Findings

Data prefer sidereal time independent solution.

Set limits on SME coefficients for Lorentz violation.

First constraints on Lorentz violation in the e-tau neutrino mixing sector.

Abstract

The Double Chooz reactor-based oscillation experiment searches for an electron antineutrino disappearance signal to investigate the neutrino mass matrix mixing angle theta 13. Double Chooz's reported evidence for this disappearance is generally interpreted as mass-driven mixing through this parameter. However, the electron antineutrino candidates collected by the experiment can also be used to search for a signature of the violation of Lorentz invariance. We study the sidereal time dependence of the antineutrino signal rate and probe Lorentz violation within the Standard-Model Extension (SME) framework. We find that the data prefer the sidereal time independent solution, and a number of limits are applied to the relevant SME coefficients, including the first constraints on those associated with Lorentz violation in the e-tau mixing sector.