FUELING LOBES OF RADIO GALAXIES: STATISTICAL PARTICLE ACCELERATION AND THE EXTRAGALACTIC {gamma}-RAY BACKGROUND
Journal Article
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· Astrophysical Journal Letters
- Harvard-Smithsonian Astrophysical Observatory, 60 Garden Street, Cambridge, MA 02138 (United States)
- SLAC National Laboratory and Kavli Institute for Particle Astrophysics and Cosmology, 2575 Sand Hill Road, Menlo Park, CA 94025 (United States)
The recent discovery of the {gamma}-ray emission from the lobes of the closest radio galaxy Centaurus A by Fermi implies the presence of high-energy electrons at least up to {gamma} {approx} 10{sup 5}-10{sup 6}. These high-energy electrons are required to interpret the observed {gamma}-ray radiation in terms of inverse Compton emission off the cosmic microwave background (IC/CMB), the widely accepted scenario to describe the X-ray emission of radio galaxy lobes. In this Letter, we consider the giant radio lobes of FR II radio galaxies showing that it is possible to maintain electrons at energies {gamma} {approx} 10{sup 5}-10{sup 6}, assuming an acceleration scenario (driven by turbulent magnetic fields) that compensates radiative losses. In addition, we consider the contribution to the diffuse extragalactic {gamma}-ray background due to the IC/CMB emission of FR IIs' lobes, showing its relevance in the keV to MeV energy range.
- OSTI ID:
- 21560459
- Journal Information:
- Astrophysical Journal Letters, Journal Name: Astrophysical Journal Letters Journal Issue: 1 Vol. 729; ISSN 2041-8205
- Country of Publication:
- United States
- Language:
- English