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Angular Anisotropies in the Cosmic Gamma-ray Background as a Probe of its Origin

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 نشر من قبل Savvas Koushiappas
 تاريخ النشر 2007
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Francesco Miniati




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Notwithstanding the advent of the Gamma-ray Large Area Telescope, theoretical models predict that a significant fraction of the cosmic gamma-ray background (CGB), at the level of 20% of the currently measured value, will remain unresolved. The angular power spectrum of intensity fluctuations of the CGB contains information on its origin. We show that probing the latter from a few tens of arcmin to several degree scales, together with complementary GLAST observations of gamma-ray emission from galaxy clusters and the blazars luminosity function, can discriminate between a background that originates from unresolved blazars or cosmic rays accelerated at structure formation shocks.



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