AI-powered algorithm sheds new light on the mass composition of cosmic rays at ultra-high energies
Researchers are paving the way for a deeper understanding of the origins of UHECR.
MoreUpdate on the large-angular-scale studies at the Pierre Auger Observatory with 19 years of data
The Pierre Auger Collaboration has published an update on large-angular-scale analyses using data from Phase 1 of the Auger Observatory.
MoreOn the hardness of the CR high-energy injection spectra
The impact of the magnetic horizon on the interpretation of the spectrum and composition data
MoreConstraints on metastable superheavy dark matter coupled to sterile neutrinos
One intriguing aspect of the Standard Model (SM) of particle physics is the absence of right-handed degrees of freedom to describe neutrinos ...
MoreBeyond the 'Muon Puzzle'
Testing hadronic interaction models using hybrid data of the Pierre Auger Observatory
MoreNew Feature found in UHECR Energy Spectrum
The energy spectrum of the highest-energy particles in the Universe, ultra-high energy cosmic rays, has been measured with the Pierre Auger Observatory with an unprecedented precision. In addition to the well-known kink in the energy spectrum, typically referred to as the ankle, a new spectral break is found at somewhat higher energy. This new break in the energy spectrum can be explained by an energy-dependent mass composition of cosmic rays. The results are published in two related papers (Phys. Rev. Lett. 125, 121106 (2020) and Phys. Rev. D 102, 062005 (2020)).
This determination of the energy spectrum is unique in having an unprecedented exposure of more than 60,000 km2 sr yr, in its method of determining the spectrum free of assumptions about the mass composition of the initial cosmic ray particle, and about details of the hadronic physics of air showers.