Related papers: Fundamental Physics With Cosmic High-Energy Gamma …
Ultra-High Energy (UHE, $>$0.1\,PeV) $\gamma$-ray Astronomy is rapidly evolving into an expanding branch of the $\gamma$-ray astronomy with the surprising discovery of 12 PeVatrons and the detection of a handful of photons above 1 PeV.…
Detection of (ultra-) high-energy cosmic rays with the use of radio frequency emission from extensive air showers has been proven as complimentary to existing ground array detection techniques. Great progress has been made in the…
The origin of ultra high energy cosmic rays promises to lead us to a deeper understanding of the structure of matter. This is possible through the study of particle collisions at center-of-mass energies in interactions far larger than…
Very high energy gamma-rays probe the long-standing mystery of the origin of cosmic rays. Produced in the interactions of accelerated particles in astrophysical objects, they can be used to image cosmic particle accelerators. A first…
The possibility that the Fermi scale is the only fundamental energy scale of Nature is under serious consideration at present, yet cosmic rays may already have provided direct evidence of new physics at a much higher scale. The recent…
Cosmic objects emit throughout the electro-magnetic spectrum, from radio waves to very high-energy gamma rays. Some spectral regions can be observed from the ground, but space instrumentation is needed for most of them. Some spectral…
An overview on the present observational status and phenomenological understanding of cosmic rays above 10^16 eV is given. Above these energies the cosmic ray flux is expected to be gradually dominated by an extra-galactic component. In…
Gamma rays constitute a privileged point of view for the study of the extreme Universe. Unlike charged cosmic rays, which are thought to have a common origin, gamma rays are not deflected by galactic and intergalactic magnetic fields. This…
We briefly review the status of cosmic ray studies between $10^{14}$ eV and the highest observed energies, namely a few times $10^{20}$ eV. Because of the rather low incident fluxes in this energy range, the studies mostly rely on ground…
Very high-energy (VHE; E>100 GeV) gamma-rays have been detected from a wide range of astronomical objects, such as pulsar wind nebulae (PWNe), supernova remnants (SNRs), giant molecular clouds, gamma-ray binaries, the Galactic Center,…
I give a concise introduction into high energy cosmic ray physics, including also few related aspects of high energy gamma-ray and neutrino astrophysics. The main emphasis is placed on astrophysical questions, and the level of the…
Cosmic rays represent one of the most important energy transformation processes of the universe. They bring information about the surrounding universe, our galaxy, and very probably also the extragalactic space, at least at the highest…
Ultra High Energy Cosmic Rays (UHECRs) interact en route to Earth, producing secondary gamma-rays. For the case of high cosmic ray power and weak intergalactic magnetic fields, the deflections of these UHECRs may be small leading to…
The High-Altitude Water Cherenkov Gamma Ray Observatory (HAWC) is designed to perform a synoptic survey of the TeV sky. The high energy coverage of the experiment will enable studies of fundamental physics beyond the Standard Model, and the…
Data obtained in the very high energy gamma-ray band with the new generation of imaging telescopes, in particular through the galactic plane survey undertaken by H.E.S.S., low threshold observations with MAGIC and more recently by operation…
Candidate astrophysical acceleration sites capable of producing the highest energy cosmic rays (E > 10^{19.5} eV) appear to be at far greater distances than is compatible with their being known particles. The properties of a new particle…
The dramatic confrontation between new observations and theories of the early and recent universe makes cosmology one of the most rapidly advancing fields in the physical sciences. The universe is a unique laboratory in which to probe…
We discuss the possibility of observing ultra high energy cosmic ray sources inhigh energy gamma rays. Protons propagating away from their accelerators produce secondary electrons during interactions with cosmic microwave background…
The observation of neutrinos from cosmic accelerators will be revolutionary. High energy neutrinos are closely connected to ultrahigh energy cosmic rays and their sources. Cosmic ray sources are likely to produce neutrinos and the…
Following the discovery of the cosmic rays by Victor Hess in 1912, more than 70 years and numerous technological developments were needed before an unambiguous detection of the first very-high-energy gamma-ray source in 1989 was made. Since…