Rejection of the Hypothesis That Markarian 501 TeV Photons Are Pure Bose-Einstein Condensates

  title={Rejection of the Hypothesis That Markarian 501 TeV Photons Are Pure Bose-Einstein Condensates},
  author={The Hegra Collaboration F. Aharonian and A. G. Akhperjanian and J. A. Barrio and et al.},
  journal={The Astrophysical Journal},
The energy spectrum of the blazar-type galaxy Markarian 501 (Mrk 501), as measured by the High-Energy Gamma-Ray Astronomy (HEGRA) air Cerenkov telescopes, extends beyond 16 TeV and constitutes the most energetic photons observed from an extragalactic object. A fraction of the emitted spectrum is possibly absorbed in interactions with low-energy photons of the diffuse extragalactic infrared radiation, which in turn offers the unique possibility to measure the diffuse infrared radiation density… 
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