Limits on Neutrino Lorentz Violation from Multimessenger Observations of TXS 0506+056

TL;DR

This paper uses multimessenger observations of the blazar TXS 0506+056 to set new stringent limits on linear and quadratic Lorentz violation in neutrino propagation, significantly improving previous constraints.

Contribution

It introduces a novel method to constrain Lorentz violation using high-energy neutrino and gamma-ray observations from a single astrophysical source.

Findings

Lower bound on the high energy scale M_1 is approximately 3 x 10^{16} GeV.

Constraints on Lorentz violation surpass previous limits by many orders of magnitude.

Results apply to both linear and quadratic Lorentz violation models.

Abstract

The observation by the IceCube Collaboration of a high-energy ($E \gtrsim 200$ TeV) neutrino from the direction of the blazar TXS 0506+056 and the coincident observations of enhanced $\gamma$-ray emissions from the same object by MAGIC and other experiments can be used to set stringent constraints on Lorentz violation in the propagation of neutrinos that is linear in the neutrino energy: $\Delta v = - E/M_1$, where $\Delta v$ is the deviation from the velocity of light, and $M_1$ is an unknown high energy scale to be constrained by experiment. Allowing for a difference in neutrino and photon propagation times of $\sim 10$ days, we find that $M_1 \gtrsim 3 \times 10^{16}$ GeV. This improves on previous limits on linear Lorentz violation in neutrino propagation by many orders of magnitude, and the same is true for quadratic Lorentz violation.