Related papers: Diffuse Galactic gamma ray flux at very high energ…
Galactic cosmic rays are energetic particles important in the context of life. Many works have investigated the propagation of Galactic cosmic rays through the Sun's heliosphere. However, the cosmic ray fluxes in M dwarf systems are still…
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…
The LHAASO Collaboration has recently reported a measurement of the diffuse gamma-ray emission from the Galactic Plane at energies between 10 TeV and 1 PeV. While this emission is brighter than that expected from cosmic-ray interactions in…
The advent of high sensitivity, high resolution gamma-ray detectors, together with a knowledge of the distribution of the atomic hydrogen and especially of the molecular hydrogen in the Galaxy on sub-degree scales creates a unique…
The measurement of gamma rays at MeV energies from cosmic radioactivities is one of the key tools for nuclear astrophysics, in its study of nuclear reactions and how they shape objects such as massive stars and supernova explosions.…
The Galactic Center region is expected to host the largest density of Dark Matter (DM) particles within the Milky Way. Then a relatively large gamma-ray signal would be expected from the possible DM particles annihilation (or decay). We are…
Context. Recent observations of unexpected structures in the Galactic Cosmic Ray (GCR) spectrum and composition, as well as growing evidence for episodes of intense dynamical activity in the inner regions of the Galaxy, call for an…
Direct measurements of cosmic ray (CR) species combined with observations of their associated gamma-ray emissions can be used to constrain models of CR propagation, trace the structure of the Galaxy, and search for signatures of new…
Recent international efforts have brought us closer to unveiling the century old mystery of the origin of cosmic rays. Cosmic ray, gamma ray, and neutrino observatories are reaching the necessary sensitivity to study the highest energy…
The gamma-ray sky >100 MeV is dominated by the diffuse emissions from interactions of cosmic rays with the interstellar gas and radiation fields of the Milky Way. Observations of these diffuse emissions provide a tool to study cosmic-ray…
Despite significant progress over more than 100 years, no accelerator has been unambiguously identified as the source of the locally measured flux of cosmic rays. High-energy electrons and positrons are of particular importance in the…
The extragalactic sources of ultra-high-energy (E > 4x10^19 eV) cosmic rays that make a small contribution to the flux of particles recorded by ground-based arrays are discussed. We show that cosmic rays from such sources can produce a…
Starburst galaxies exhibit in their central regions a highly increased rate of supernovae, the remnants of which are thought to accelerate energetic cosmic rays up to energies of ~ 10^15 eV. We report the detection of gamma rays -- tracers…
An important contribution to the gamma-ray emission of our Galaxy is the Galactic Diffuse emission. We present specific developments within the PICARD code for modeling of Galactic cosmic ray propagation that are relevant for the…
Galactic X-ray emission is a manifestation of various high-energy phenomena and processes. The brightest X-ray sources are typically accretion-powered objects: active galactic nuclei and low- or high-mass X-ray binaries. Such objects with…
One of the unsolved problems in cosmic ray (CR) physics is the small radial gradient of the gamma-ray intensity compared to the inferred CR source distribution in the Galactic disk. In diffusive CR propagation models the most natural…
This Chapter provides a review of $\gamma$-ray sources lying at high Galactic latitudes. Their statistical properties and variability status, as well as studies involving cross correlations with lower frequency catalogs and multiwavelength…
The gamma-ray background is still a subject under great debate. All phenomena in the universe emitting gamma-rays can contribute directly as diffuse emission or as an isotropic component from unresolved point sources. The question of the…
We performed a spectro-morphological analysis of the diffuse emission in the Galactic center region with H.E.S.S. gamma-ray data. We relied on templates to model the diffuse emissions (the Galactic center ridge and the foreground component)…
Analytical calculations of extra-galactic cosmic ray spectra above ~10^17 eV are often performed assuming continuous source distributions, giving rise to spectra that depend little on the propagation mode, be it rectilinear or diffusive. We…