A new determination of the extragalactic diffuse gamma-ray background from EGRET data
Abstract
We use the GALPROP model for cosmic-ray propagation to obtain a new estimate of the Galactic component of gamma rays, and show that away from the Galactic plane it gives an accurate prediction of the observed EGRET intensities in the energy range 30 MeV - 50 GeV. On this basis we re-evaluate the extragalactic gamma-ray background. We find that for some energies previous work underestimated the Galactic contribution at high latitudes and hence overestimated the background. Our new background spectrum shows a positive curvature similar to that expected for models of the extragalactic emission based on the blazar population.
Cite
@article{arxiv.astro-ph/0405441,
title = {A new determination of the extragalactic diffuse gamma-ray background from EGRET data},
author = {A. W. Strong and I. V. Moskalenko and O. Reimer},
journal= {arXiv preprint arXiv:astro-ph/0405441},
year = {2009}
}
Comments
Accepted for publication in The Astrophysical Journal; 6 pages, 14 ps-figures, 4 tables emulateapj.sty, natbib.sty, aastex.cls. More details can be found at http://www.gamma.mpe-garching.mpg.de/~aws/aws.html