Constraints on violation of Lorentz invariance from atmospheric showers initiated by multi-TeV photons

TL;DR

This paper investigates how potential Lorentz invariance violations at high energies could alter atmospheric shower formation by gamma rays, using observational data to set competitive bounds on such violations.

Contribution

It introduces a method to constrain Lorentz invariance violation using atmospheric shower data from gamma-ray observations, providing bounds comparable to other astrophysical tests.

Findings

No suppression of atmospheric showers observed at high energies

Established lower bounds on the energy scale of Lorentz invariance violation

Bounds are competitive with constraints from astrophysical source timing

Abstract

We discuss the effect of hypothetical violation of Lorentz invariance at high energies on the formation of atmospheric showers by very-high-energy gamma rays. In the scenario where Lorentz invariance violation leads to a decrease of the photon velocity with energy the formation of the showers is suppressed compared to the Lorentz invariant case. Absence of such suppression in the high-energy part of spectrum of the Crab nebula measured independently by HEGRA and H.E.S.S. collaborations is used to set lower bounds on the energy scale of Lorentz invariance violation. These bounds are competitive with the strongest existing constraints obtained from timing of variable astrophysical sources and the absorption of TeV photons on the extragalactic background light. They will be further improved by the next generation of multi-TeV gamma-ray observatories.