Galactic origin of the alleged extragalactic gamma-ray background radiation

Arnon Dar

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arXiv · astro-ph/0107429

Galactic origin of the alleged extragalactic gamma-ray background radiation

Arnon Dar

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Abstract

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 extended CR halo of our galaxy. Assuming the locally observed CR electron spectrum beyond a few GeV, which follows from equilibrium between Fermi acceleration and radiative cooling, to be a universal spectrum throughout our galaxy and its CR halo, we reproduce the observed spectral index, the intensity and the angular dependence of the GBR, in directions away from the galactic disk and centre, without recourse to hypothetical extragalactic sources.

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Arnon Dar. 2001-07-22. Galactic origin of the alleged extragalactic gamma-ray background radiation. https://arxiv.org/abs/astro-ph/0107429

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