Constraining the sources of ultra-high-energy cosmic rays with experimental measurements

by Teresa Bister (Radboud University)

Tuesday 21 Jul 2026, 16:00 → 17:00 Europe/Berlin

ENC-D308

Ultra-high-energy cosmic rays (UHECRs) are the most energetic particles known - and yet their origin is still an open question. However, leveraging the precision and accumulated statistics of the largest observatory in the world, the Pierre Auger Observatory, it is now possible to set constraints on the sources of UHECRs. The spectrum and mass composition measurements at the highest energies can be well described by a population of extragalactic, homogeneously distributed sources. Utilizing additionally the observed anisotropy in the UHECR arrival directions - and interpreting it using models of the Galactic magnetic field that deflects UHECRs on their way to us - even more powerful constraints on the density and distribution of sources can be placed. The status and possible interpretation of UHECR measurements will be reviewed in this presentation.