Probing Lorentz Invariance Violation in Cosmogenic Neutrino Propagation with KM3-230213A

Abstract

We investigate superluminal Lorentz invariance violation (LIV) in the neutrino sector using cosmogenic neutrino fluxes generated with ultrahigh-energy cosmic-ray propagation models. Standard fluxes are calculated with CRPropa 3.2 and subsequently modified using a prescription based on LIV-induced neutrino splitting. Superluminal LIV suppresses the flux at the highest energies while producing an enhancement at PeV - EeV energies. We use the KM3-230213A event as a benchmark to evaluate the sensitivity of current observations to these spectral modifications. Although the available statistics do not allow a formal constraint, the predicted fluxes are particularly sensitive to coefficients in the range 10−24 eV−1 ≲ δν, 1 ≲ 10−22 eV−1, with the results strongly depending on the assumed cosmic-ray source properties. Intermediate coefficients can enhance the expected event rate within the reconstructed energy range of KM3-230213A, whereas larger coefficients may overproduce neutrinos in energy intervals constrained by IceCube and the Pierre Auger Observatory. These results identify a region of observational sensitivity to LIV and provide testable predictions for future neutrino telescopes.