Constraints on diffuse gamma-ray emission from structure formation processes in the Coma cluster

摘要: We analyse five-year (63 months) data of the Large Area Telescope on board Fermi satellite from Coma galaxy cluster in energy range between 100 MeV and GeV. The likelihood analyses are performed with several templates motivated by models predicting gamma-ray emission due to structure formation processes. find no excess derive most stringent constraints date above MeV, tested scenarios general. upper limits integral flux 10−10 10−9 cm−2 s−1, enough challenge different scenarios. that acceleration efficiency cosmic ray protons electrons at shocks must be below approximately 15 1 per cent, respectively. Additionally, we argue proton should lower than 5 per cent order consistent radio data. This, however, relies magnetic field estimates cluster. In particular, this implies contribution diffuse extragalactic background gamma-rays processes clusters galaxies is negligible, per cent. Finally, discuss future detectability prospects for Astro-H, after 10-yr operation, Cherenkov Array.