Related papers: High Energy Gamma Rays
We introduce neutrino astronomy starting from the observational fact that Nature accelerates protons and photons to energies in excess of 10^{20} and 10^{13} eV, respectively. Although the discovery of cosmic rays dates back a century, we…
I review here some of the main observational features in microquasars and AGNs as sources of high-energy gamma-rays as well as some of the current models that try to explain the emission in the gamma-ray domain.
Here is reviewed our current understanding of Galactic and extragalactic diffuse gamma-ray emission. The spectrum of the extragalactic gamma-ray background above 30 MeV can be well described by a power law with photon index s=2.1. In the…
Gamma rays reveal extreme, nonthermal conditions in the Universe. The Fermi Gamma-ray Space Telescope has been exploring the gamma-ray sky for more than four years, enabling a search for powerful transients like gamma-ray bursts, solar…
As of early 2009, latest results on Galactic sources (mainly shell-type and plerionic supernova remnants), as observed in the very-high-energy gamma-ray domain, are reviewed. A particular attention is given to those obtained with the…
We will discuss the main relevant aspects of the physics of ultra high energy cosmic rays. After a short recap of the experimental evidences, we will review theoretical models aiming at describing the sources of these extremely energetic…
After seven years of science operation, the Fermi mission has brought great advances in the study of Gamma-ray Bursts (GRBs). Over 1600 GRBs have been detected by the Gamma-ray Burst Monitor, and more than 100 of these are also detected by…
Cosmic gamma-ray bursts are one of the great frontiers of astrophysics today. They are a playground of relativists and observers alike. They may teach us about the death of stars and the birth of black holes, the physics in extreme…
The sheer number of new gamma-ray pulsar discoveries by the Fermi Large Area Telescope since 2008, combined with the quality of new multi-frequency data, has caused a revolution in the field of high-energy rotation-powered pulsars. These…
The development of the atmospheric Cherenkov imaging technique has led to significant advances in gamma-ray detection sensitivity in the energy range from 200 GeV to 50 TeV. The Whipple Observatory 10m reflector has detected the first…
Selected results from the HEGRA experiment on charged Cosmic Rays and on very high energy gamma-rays are presented. The MAGIC Telescope is presented as an outlook to the future of Gamma-Ray astronomy.
We discuss the ability of the GLAST Large Area Telescope (LAT) to identify, resolve, and study the high energy gamma-ray sky. Compared to previous instruments the telescope will have greatly improved sensitivity and ability to localize…
The most energetic neutron stars, powered by their rotation, are capable of producing pulsed radiation from the radio up to gamma rays with nearly TeV energies. These pulsars are part of the universe of energetic and powerful particle…
We address some current theoretical issues around ultra-high energy cosmic rays. We recall that scenarios producing more gamma-rays than cosmic rays up to high redshift can in general only provide a sub-dominant contribution to the…
This work intends to provide a brief summary of some of the Galactic science issues for the next generation of very high energy (VHE) instruments. The latter is here generically understood, as an instrument or set of instruments providing…
One way to understand the nonthermal history of the universe is by establishing the origins of the unresolved and truly diffuse extragalactic gamma rays. Dim blazars and radio/gamma galaxies certainly make an important contribution to the…
The last few years have seen gamma-ray astronomy maturing and advancing in the field of time-domain astronomy, utilizing source variability on timescales over many orders of magnitudes, from a decade down to a few minutes and shorter,…
We briefly review sources of cosmic rays, their composition and spectra as well as their propagation in the galactic and extragalactic magnetic fields, both regular and fluctuating. A special attention is paid to the recent results of the…
The study of high energy cosmic rays is a diversified field of observational and phenomenological physics addressing questions ranging from shock acceleration of charged particles in various astrophysical objects, via transport properties…
The impact of non-thermal processes on the spectral energy distributions of galaxies can be dramatic, but such processes are often neglected in considerations of their structure and evolution. Particle acceleration associated with high mass…