The Extragalactic Gamma Ray Background
Astrophysics
2009-06-23 v2
Abstract
One way to understand the nonthermal history of the universe is by establishing the origins of the unresolved and truly diffuse extragalactic gamma rays. Dim blazars and radio/gamma galaxies certainly make an important contribution to the galactic gamma-ray background given the EGRET discoveries, and previous treatments are reviewed and compared with a new analysis. Studies of the gamma-ray intensity from cosmic rays in star-forming galaxies and from structure formation shocks, as well as from dim GRBs, are briefly reviewed. A new hard gamma-ray source class seems required from the predicted aggregate intensity compared with the measured intensity.
Cite
@article{arxiv.0704.2888,
title = {The Extragalactic Gamma Ray Background},
author = {Charles D. Dermer},
journal= {arXiv preprint arXiv:0704.2888},
year = {2009}
}