English

A new model for the Fermi-LAT Extragalactic Gamma-Ray Background

High Energy Astrophysical Phenomena 2011-11-01 v1

Abstract

We compute the contribution of blazars (Flat Spectrum Radio Quasars and BL-Lacs) to the Fermi-LAT Extragalactic gamma-ray Background, assuming a gamma-ray luminosity function proportional to the luminosity function of radio galaxies and the Spectral Energy Distribution of blazars given by the so-called blazar sequence. We find that blazars account for the 45% of the total Fermi-LAT EGB. However, at low (<10 GeV) and high (>50 GeV) energies the blazar contribution falls short to account for the observed background light. At E<10 GeV, the Extragalactic gamma-ray Background can be fully explained by considering the additional contribution of star-forming galaxies, whereas at very high energies, where the absorption due to Extragalactic Background Light dominates, the observed background calls for an additional unknown component.

Keywords

Cite

@article{arxiv.1110.6889,
  title  = {A new model for the Fermi-LAT Extragalactic Gamma-Ray Background},
  author = {Massimo Cavadini and Ruben Salvaterra and Francesco Haardt},
  journal= {arXiv preprint arXiv:1110.6889},
  year   = {2011}
}

Comments

2011 Fermi Symposium proceedings - eConf C110509

R2 v1 2026-06-21T19:28:36.347Z