The science of ultra-high energy cosmic rays after more than 15 years of operation of the Pierre Auger Observatory

Abstract

The Pierre Auger Observatory has been detecting ultra-high energy cosmic rays (UHECRs) for more than fifteen years. An essential feature of the Observatory is its hybrid design: cosmic rays above $100$PeV are detected through the observation of the associated air showers with different and complementary techniques, from surface detector arrays and fluorescence telescopes to radio antennas. The analyses of the multi-detector data have enabled high-statistics and high-precision studies of the energy spectrum, mass composition and distribution of arrival directions of UHECRs. The resulting picture is summarized in this contribution. While no discrete source of UHECRs has been identified so far, the extragalactic origin of the particles has been recently determined from the arrival directions above 8~EeV, and the ring is closing around nearby astrophysical sites at higher energies. Also, the established upper limits on fluxes of UHE neutrinos and photons have implications on dark matter and cosmological aspects that are also presented in this contribution.

Proceedings of the 12th Cosmic Ray International Seminar - CRIS 2022 - September 12-16, 2022, Napoli, Italy - to appear in Journal of Physics Conference Series

References in corpus (11)

• Observation of a Large-scale Anisotropy in the Arrival Directions of Cosmic Rays above $8\times 10^{18}$ eV
• Measurement of the proton-air cross-section at $\sqrt{s}=57$ TeV with the Pierre Auger Observatory
• Testing Hadronic Interactions at Ultrahigh Energies with Air Showers Measured by the Pierre Auger Observatory
• Measurement of the cosmic-ray energy spectrum above $2.5\times 10^{18}$ eV using the Pierre Auger Observatory
• Features of the energy spectrum of cosmic rays above $2.5\times 10^{18}$ eV using the Pierre Auger Observatory
• The energy spectrum of cosmic rays beyond the turn-down around $10^{17}$ eV as measured with the surface detector of the Pierre Auger Observatory
• Arrival Directions of Cosmic Rays above 32 EeV from Phase One of the Pierre Auger Observatory
• Measurement of the fluctuations in the number of muons in extensive air showers with the Pierre Auger Observatory
• A search for photons with energies above $2\times 10^{17}$ eV using hybrid data from the low-energy extensions of the Pierre Auger Observatory
• Multi-Messenger Physics with the Pierre Auger Observatory
• A search for ultra high energy neutrinos from TXS 0506+056 using the Pierre Auger Observatory

Cited by in corpus (1)

• Possible contribution of X-ray binary jets to the Galactic cosmic ray and neutrino flux