Threshold anomalies of ultra-high energy cosmic photons due to Lorentz invariance violation

Context. High-energy photons emitted by flaring active galactic nuclei (AGNs) have been used for many years to constrain modified dispersion relations in vacuum encountered in the context of quantum gravity phenomenology. In such studies, done in the GeV–TeV range, energy-dependent delays (spectral lags) are searched for, usually neglecting any source-intrinsic time delay. Aims. With the aim being to distinguish Lorentz invariance violation (LIV) effects from lags generated at the sources themselves, a detailed investigation into intrinsic spectral lags in flaring AGNs above 100 GeV is presented in the frame of synchrotron-self-Compton scenarios for their very-high-energy (VHE) emission. Methods. A simple model of VHE flares in blazars is proposed, allowing to explore the influence of the main physical parameters describing the emitting zones on intrinsic delays. Results. For typical conditions expected in TeV blazars, significant intrinsic lags are obtained, which can dominate over LIV effects, especially at low redshifts, and should therefore be carefully disentangled from any extrinsic lags. Moreover, two main regimes are identified with characteristic spectral lags, corresponding to long-lasting and fast particle acceleration. Conclusions. Such intrinsic spectral lags should be detected with new-generation instruments at VHE such as the Cherenkov Telescope Array which begins operation in a few years. This will provide original constraints on AGN flare models and open a new era for LIV searches in the photon sector.

Lorentz Violation Footprints in the Spectrum of High-Energy Cosmic Neutrinos—Deformation of the Spectrum of Superluminal Neutrinos from Electron-Positron Pair Production in Vacuum

Symmetry ◽

10.3390/sym11111419 ◽

2019 ◽

Vol 11 (11) ◽

pp. 1419 ◽

Cited By ~ 2

Author(s):

José Manuel Carmona ◽

José Luis Cortés ◽

José Javier Relancio ◽

Maykoll Anthonny Reyes

Keyword(s):

Pair Production ◽

Numerical Simulations ◽

Lorentz Invariance ◽

Lorentz Violation ◽

High Energy ◽

Energy Scale ◽

Invariance Violation ◽

Electron Positron ◽

Lorentz Invariance Violation ◽

Electron Positron Pair

The observation of cosmic neutrinos up to 2 PeV is used to put bounds on the energy scale of Lorentz invariance violation through the loss of energy due to the production of e + e - pairs in the propagation of superluminal neutrinos. A model to study this effect, which allows us to understand qualitatively the results of numerical simulations, is presented.

HIGH ENERGY ASTROPHYSICS TESTS OF LORENTZ INVARIANCE VIOLATION

International Journal of Modern Physics A ◽

10.1142/s0217751x05025966 ◽

2005 ◽

Vol 20 (14) ◽

pp. 3139-3142 ◽

Cited By ~ 4

Author(s):

F. W. STECKER

Keyword(s):

Lorentz Invariance ◽

High Energy ◽

Ultrahigh Energy ◽

Large Extra Dimension ◽

Bl Lac Objects ◽

Invariance Violation ◽

Electron Positron ◽

Lorentz Invariance Violation ◽

Emission Models ◽

Flux Level

Observations of the multi-TeV spectra of the Mkn 501 and other nearby BL Lac objects exhibit the high energy cutoffs predicted to be the result of intergalactic annihilation interactions, primarily with IR photons having a flux level as determined by various astronomical observations. After correcting for such intergalactic absorption, these spectra can be explained within the framework of synchrotron self-Compton emission models. Stecker and Glashow have shown that the existence of this annihilation via electron-positron pair production puts strong constraints on Lorentz invariance violaition. Such constraints have important implications for some quantum gravity and large extra dimension models. A much smaller amount of Lorentz invariance violation has potential implications for understanding the spectra of ultrahigh energy cosmic rays.

HIGH ENERGY NEUTRINO OSCILLATION AT THE PRESENCE OF THE LORENTZ INVARIANCE VIOLATION

International Journal of Modern Physics A ◽

10.1142/s0217751x12501047 ◽

2012 ◽

Vol 27 (19) ◽

pp. 1250104 ◽

Cited By ~ 8

Author(s):

IMAN MOTIE ◽

SHE-SHENG XUE

Keyword(s):

Neutrino Oscillation ◽

Lorentz Invariance ◽

Planck Scale ◽

High Energy ◽

Oscillation Pattern ◽

High Energies ◽

Invariance Violation ◽

Lorentz Invariance Violation ◽

Very High Energy ◽

Very High

Due to quantum gravity fluctuations at the Planck scale, the space–time manifold is no longer continuous, but discretized. As a result the Lorentz symmetry is broken at very high energies. In this paper, we study the neutrino oscillation pattern due to the Lorentz invariance violation (LIV), and compare it with the normal neutrino oscillation pattern due to neutrino masses. We find that at very high energies, neutrino oscillation pattern is very different from the normal one. This could provide an possibility to study the Lorentz invariance violation by measuring the oscillation pattern of very high energy neutrinos from a cosmological distance.