The exploration of the universe has recently entered a new era thanks to the multi-
messenger paradigm, characterized by a continuous increase in the quantity and quality of …

Understanding the physical mechanisms that control galaxy formation is a fundamental
challenge in contemporary astrophysics. Recent advances in the field of astrophysical …

The present white paper is submitted as part of the “Snowmass” process to help inform the
long-term plans of the United States Department of Energy and the National Science …

Astrophysical neutrinos are excellent probes of astroparticle physics and high-energy
physics. With energies far beyond solar, supernovae, atmospheric, and accelerator …

We report a measurement of the energy spectrum of cosmic rays for energies above 2.5× 10
18 eV based on 215,030 events recorded with zenith angles below 60°. A key feature of the …

Cosmic rays are energetic charged particles from extraterrestrial sources, with the highest-
energy events thought to come from extragalactic sources. Their arrival is infrequent, so …

Abstract The Probe Of Extreme Multi-Messenger Astrophysics (POEMMA) is designed to
accurately observe ultra-high-energy cosmic rays (UHECRs) and cosmic neutrinos from …

We present a measurement of the cosmic-ray spectrum above 100 PeV using the part of the
surface detector of the Pierre Auger Observatory that has a spacing of 750 m. An inflection of …

Cosmic rays are observed up to the astounding energies of more than 1020 eV, making
them the most energetic particles known in the universe. However, the origin of these …

In this work we present the interpretation of the energy spectrum and mass composition data
as measured by the Pierre Auger Collaboration above 6× 1017 eV. We use an astrophysical …