The exploration of the universe has recently entered a new era thanks to the multi-
messenger paradigm, characterized by a continuous increase in the quantity and quality of …

One of the most promising ways to probe intergalactic magnetic fields (IGMFs) is through
gamma rays produced in electromagnetic cascades initiated by high-energy gamma rays or …

The Cherenkov Telescope Array (CTA), the new-generation ground-based observatory for γ-
ray astronomy, provides unique capabilities to address significant open questions in …

The unification of quantum mechanics and general relativity has long been elusive. Only
recently have empirical predictions of various possible theories of quantum gravity been put …

The most powerful persistent accelerators in the Universe are jetted active galaxies. Blazars,
galaxies whose jets are directed towards Earth, dominate the extragalactic γ-ray sky. Still …

On January 14, 2019, the Major Atmospheric Gamma Imaging Cherenkov telescopes
detected GRB 190114C above 0.2 TeV, recording the most energetic photons ever …

Recently, the LHAASO Collaboration published the detection of 12 ultrahigh-energy γ-ray
sources above 100 TeV, with the highest energy photon reaching 1.4 PeV. The first …

The propagation of gamma-rays over cosmological distances is the subject of extensive
theoretical and observational research at GeV and TeV energies. The mean free path of …

In this review, we present the latest exclusion limits obtained from astroparticles on Lorentz
Invariance Violation (LIV) in the photon sector. We discuss the techniques known as energy …

Motivated by the recently reported evidence of an association between a high-energy
neutrino and a γ-ray flare from the blazar TXS 0506+ 056, we calculate the expected high …