The gamma ray background from large scale structure formation
نویسندگان
چکیده
منابع مشابه
The gamma ray background from large scale structure formation
Hierarchical clustering of dark matter halos is thought to describe well the large scale structure of the universe. The baryonic component of the halos is shock heated to the virial temperature while a small fraction of the energy flux through the shocks may be energized through the first order Fermi process to relativistic energy per particle. It has been proposed that the electrons accelerate...
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The origin of the diffuse extragalactic, high-energy gamma-ray background (EGRB) filling the Universe remains unknown. The spectrum of this extragalactic radiation, as measured by the Energetic Gamma Ray Experiment Telescope (EGRET) on-board the Compton Gamma-Ray Observatory (CGRO), is well-fit by a power law across nearly four decades in energy, from 30 MeV to 100 GeV. It has been estimated th...
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The Universe is filled with a diffuse background of gamma-ray radiation, the origin of which remains one of the unsolved puzzles of cosmology. Less than one-quarter of the gamma-ray flux can be attributed to unresolved discrete sources, such as active galactic nuclei; the remainder appears to constitute a truly diffuse background. Here we show that the shock waves induced by gravity in the gas ...
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ژورنال
عنوان ژورنال: Astroparticle Physics
سال: 2003
ISSN: 0927-6505
DOI: 10.1016/s0927-6505(03)00106-3