An Exceptional Very High Energy Gamma-Ray Flare of PKS 2155-304

  title={An Exceptional Very High Energy Gamma-Ray Flare of PKS 2155-304},
  author={Felix Aharonian and et al.},
  journal={The Astrophysical Journal},
The high-frequency peaked BL Lac PKS 2155-304 at redshift z = 0.116 is a well-known VHE (>100 GeV) γ-ray emitter. Since 2002 its VHE flux has been monitored using the H.E.S.S. stereoscopic array of imaging atmospheric Cerenkov telescopes in Namibia. During the 2006 July dark period, the average VHE flux was measured to be more than 10 times typical values observed from the object. This article focuses solely on an extreme γ-ray outburst detected in the early hours of 2006 July 28 (MJD 53,944… 

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