Conveners
Cosmic Rays: - 2
- Paolo Desiati (University of Wisconsin - Madison)
- Philipp Mertsch (TTK, RWTH Aachen University)
High-energy cosmic rays interact in the Earth's atmosphere and produce extensive air showers (EAS) which can be measured with large detector arrays at the ground. The interpretation of these measurements relies on sophisticated models of the EAS development which represents a challenge as well as an opportunity to test quantum chromodynamics (QCD) under extreme conditions. The EAS development...
The Pierre Auger Observatory has gathered an unprecedented dataset of ultrahigh-energy cosmic rays, thanks to its large aperture and more than 15 years of activity. We present here the highest energy events observed by the Observatory between 2004 and 2020, i.e., before the AugerPrime upgrade. With a cumulative exposure of ~120000 km2 sr yr, we collected more than 2600 events above 32 EeV....
We present a combined fit of a simple astrophysical model of Ultra-high-energy cosmic rays (UHECRs) sources to both the energy spectrum and mass composition data measured by the Pierre Auger Observatory. The astrophysical model we adopted consists of identical sources uniformly distributed in a comoving volume, where nuclei are accelerated with a rigidity-dependent mechanism. The fit has...
The origin of ultra-high-energy cosmic rays (UHECRs) is still unknown. Their sources are believed to be within the local universe (a few hundred megaparsecs), but deflections by intergalactic and Galactic magnetic fields prevent us from straightforwardly associating UHECRs to their sources based on their arrival directions, making their angular distribution mostly isotropic. At higher...
The arrival directions of cosmic rays are highly isotropic which is expected due to the interaction between these particles and magnetic turbulence in the interstellar medium. High-statistics observatories like IceCube and HAWC have however observed significant deviations from isotropy down to very small angular scales. Such small-scale anisotropies could not be predicted in the standard...
