Simulating Electromagnetic Cascades with Lorentz Invariance Violation

TL;DR

This paper explores how Lorentz invariance violation (LIV) affects gamma-ray electromagnetic cascades, revealing observable signatures that could be detected in high-energy gamma-ray measurements, thus providing a way to test quantum gravity models.

Contribution

The study provides detailed numerical simulations of LIV effects on gamma-ray cascades, including processes forbidden in the Standard Model, offering new insights into potential observational signatures.

Findings

LIV modifies gamma-ray flux characteristics at Earth.

Distinct signatures of LIV could be observed in high-energy gamma-ray data.

Inclusion of forbidden processes like vacuum Cherenkov emission enhances the analysis.

Abstract

Lorentz invariance violation (LIV) is a phenomenon featuring in various quantum gravity models whereby Lorentz symmetry is broken at high energies, potentially impacting the behaviour of particles and their interactions. Here we investigate the phenomenology of LIV within the context of gamma-ray-induced electromagnetic cascades. We conduct detailed numerical simulations to explore the expected manifestations of LIV on gamma-ray fluxes, taking into account relevant effects such as pair production and inverse Compton scattering. Additionally, we consider processes forbidden in the Standard Model, namely vacuum Cherenkov emission and photon decay. Our analysis reveals that these modifications result in distinct characteristics within the measured particle fluxes at Earth, which have the potential to be observed in high-energy gamma-ray observations.