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Gamma Ray Signals from Cosmic Ray Scattering on Axion-Like Particles

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 نشر من قبل Ian Shoemaker
 تاريخ النشر 2020
  مجال البحث
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Dark Matter (DM) may be comprised of axion-like particles (ALPs) with couplings to photons and the standard model fermions. In this paper we study photon signals arising from cosmic ray (CR) electron scattering on background ALPs. For a range of masses we find that these bounds can place competitive new constraints on the ALP-electron coupling, although in many models lifetime constraints may supersede these bounds. In addition to current Fermi constraints, we also consider future e-Astrogram bounds which will have greater sensitivity to ALP-CR induced gamma-rays.

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