Related papers: Evidence for a Galactic gamma ray halo
Progress in the Imaging Atmospheric Cherenkov Technique has enabled first sensitive observations of the innermost few 100 pc of the Milky Way in Very High Energy (VHE; >100 GeV) gamma rays. Observations by the H.E.S.S. instrument deliver…
Galactic halo gas traces inflowing star formation fuel and feedback from a galaxy's disk and is therefore crucial to our understanding of galaxy evolution. In this review, we summarize the multi-wavelength observational properties and…
The distribution of cosmic rays in the Galaxy at energies above few TeVs is still uncertain and this affects the expectations for the diffuse gamma flux produced by hadronic interactions of cosmic rays with the interstellar gas. We show…
We give a review of cosmic ray propagation models. It is shown that the development of the theory of cosmic ray origin leads inevitably to the conclusion that cosmic ray propagation in the Galaxy is determined by effective particle…
We discuss uncertainties and possible sources of errors associated with the determination of the diffuse Galactic gamma-ray emission using the EGRET data. Most of the issues will be relevant also in the GLAST era. The focus here is on…
Galaxies are thought to grow through accretion; as less massive galaxies are disrupted and merge over time, their debris results in diffuse, clumpy stellar halos enveloping the central galaxy. Here we present a study of the variation in the…
Gamma-ray emission from a narrow band at the Galactic equator has previously been detected up to 30 GeV. We report evidence for a TeV gamma-ray signal from the Galactic plane by Milagro, a large field of view water Cherenkov detector for…
We calculate the flux of radio, hard X-ray and UV radiation from clusters of galaxies as produced by synchrotron emission and Inverse Compton Scattering of electrons generated as secondaries in cosmic ray interactions in the intracluster…
Continuum low-frequency radio observations of the Galactic Center reveal the presence of two prominent radio sources, Sgr A East and its surrounding Halo, containing non-thermal particle distributions with power-law indices around 2.5-3.3…
We have performed an analysis of the diffuse gamma-ray emission with the Fermi Large Area Telescope in the Milky Way Halo region searching for a signal from dark matter annihilation or decay. In the absence of a robust dark matter signal,…
The BATSE experiment on GRO has demonstrated the isotropic arrival directions and flat $\log N$ {\it vs.} $\log S$ of cosmic gamma-ray bursts. These data are best explained if the burst sources are distributed throughout an extended…
We exploit the first \gaia data release to study the properties of the Galactic stellar halo as traced by RR Lyrae. We demonstrate that it is possible to select a pure sample of RR Lyrae using only photometric information available in the…
The observation of the diffuse Galactic gamma ray flux is the most powerful tool to study cosmic rays in different regions of the Galaxy, because the energy and angular distributions of the photons encode information about the density and…
Using the HEGRA system of imaging atmospheric Cherenkov telescopes, a region of the Galactic plane (-10 deg < b < 5 deg, 38 deg < l < 43 deg) was surveyed for TeV gamma-ray emission, both from point sources and of diffuse nature. The region…
Recent full-sky maps of the Galaxy from the Fermi Gamma-Ray Space Telescope have revealed a diffuse component of emission towards the Galactic center and extending up to roughly +/-50 degrees in latitude. This Fermi "haze" is the inverse…
In the course of its operation, the EGRET experiment detected high-energy gamma ray sources at energies above 100 MeV over the whole sky. In this communication, we search for large-scale anisotropy patterns among the catalogued EGRET…
The diffuse gamma-ray background radiation (GBR) at high Galactic latitudes could be dominated by inverse Compton scattering (ICS) of cosmic ray (CR) electrons on the cosmic microwave background radiation (CBR) and on starlight (SL) in an…
The Earth's high energy gamma-ray emission is caused by cosmic ray interactions with the atmosphere. The EGRET detector on-board the CGRO satellite is only the second experiment (after SAS-2) to provide a suitable dataset for the…
The total cosmic-ray luminosity of the Galaxy is an important constraint on models of cosmic-ray generation. The diffuse high energy $\gamma$-ray and radio-synchrotron emissions of the Milky Way are used to derive this luminosity. The…
We analyze the gamma-ray sky at energies of 0.5 to 50 GeV using the undecimated wavelet transform on the sphere. Focusing on the inner $60^{\circ} \times 60^{\circ}$ of the sky, we identify and characterize four separate residuals beyond…