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 …

We review open questions and prospects for progress in ultrahigh-energy cosmic ray
(UHECR) research, based on a series of discussions that took place during the “The High …

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 …

While astrophysical and cosmological probes provide a remarkably precise and consistent
picture of the quantity and general properties of dark matter, its fundamental nature remains …

Weakly interacting neutrinos are ideal astronomical messengers because they travel
through space without deflection by magnetic fields and, essentially, without absorption …

This report summarizes the findings of the CF1 Topical Subgroup to Snowmass 2021, which
was focused on particle dark matter. One of the most important scientific goals of the next …

The interaction of ultra-high-energy cosmic rays (UHECRs) with pervasive photon fields
generates associated cosmogenic fluxes of neutrinos and photons due to photohadronic …

Lorentz invariance violation (LIV) is often described by dispersion relations of the form E2 i=
m2 i+ p2 i+ δi, nE2+n with delta different based on particle type i, with energy E, momentum …

In this report we review the important progress made in recent years towards understanding
the experimental data on ultra-high-energy (E≳ 1 0 9 GeV) cosmic rays. We begin with a …

We review some of the recent progress in our knowledge about high-energy cosmic rays,
with an emphasis on the interpretation of the different observational results. We discuss the …