We examine the theoretical motivations for long-lived particle (LLP) signals at the LHC in a
comprehensive survey of standard model (SM) extensions. LLPs are a common prediction of …

In this paper we review air shower data related to the mass composition of cosmic rays
above 1015eV. After explaining the basic relations between air shower observables and the …

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 the simulation framework CRPropa version 3 designed for efficient development
of astrophysical predictions for ultra-high energy particles. Users can assemble modules of …

We present the first hybrid measurement of the average muon number in air showers at
ultrahigh energies, initiated by cosmic rays with zenith angles between 62 and 80. The …

Abstract The Pierre Auger Observatory, located on a vast, high plain in western Argentina, is
the world׳ s largest cosmic ray observatory. The objectives of the Observatory are to probe …

In the last fifteen years radio detection made it back to the list of promising techniques for
extensive air showers, firstly, due to the installation and successful operation of digital radio …

The origin of the highest energy cosmic rays is still unknown. The discovery of their sources
is expected to reveal the workings of the most energetic astrophysical accelerators in the …

I review the current status of phenomenological programs inspired by quantum-spacetime
research. I stress in particular the significance of results establishing that certain data …

The afterglow emission from gamma-ray bursts (GRBs) is usually interpreted as synchrotron
radiation from electrons accelerated at the GRB external shock that propagates with …