The case for a low extragalactic gamma-ray background

  title={The case for a low extragalactic gamma-ray background},
  author={Uri Keshet and Eli Waxman and Abraham Loeb},
  journal={Journal of Cosmology and Astroparticle Physics},
Measurements of the diffuse extragalactic γ-ray background (EGRB) are complicated by a strong Galactic foreground. Estimates of the EGRB flux and spectrum, obtained by modelling the Galactic emission, have produced a variety of (sometimes conflicting) results. The latest analysis of the EGRET data found an isotropic flux Ix = 1.45±0.05 above 100 MeV, in units of 10−5 ph s−1 cm−2 sr−1. We analyse the EGRET data in search of robust constraints on the EGRB flux, finding the γ-ray sky strongly… 

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