The Pierre Auger Collaboration has searched for the possible presence of photons with energies exceeding 1018 eV in the flux of cosmic rays arriving at Earth.
When an ultrahigh-energy cosmic ray impacts the Earth’s atmosphere, it can generate an enormous cascade of billions of energetic particles capable of reaching the ground.
One of the most pressing mysteries in astroparticle physics is the composition and origin of cosmic rays at energies around 1 EeV = 1018 eV.
100 years after their prediction by Albert Einstein, Gravitational Waves (GW) were detected in 2015 by the LIGO detectors.
The highest energy cosmic rays remain elusive and mysterious, and their study requires extraordinary efforts.
Maxwell’s unified description of electric and magnetic phenomena is one of the greatest achievements of 19th century physics.