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Detection of VHE radiation from the BL Lac PG 1553+113 with the MAGIC telescope

J. Albert et al.
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Abstract

In 2005 and 2006, the MAGIC telescope has observed very high energy gamma-ray emission from the distant BL Lac object PG 1553+113. The overall significance of the signal is 8.8 sigma for 18.8h observation time. The light curve shows no significant flux variations on a daily time-scale, the flux level during 2005 was, however, significantly higher compared to 2006. The differential energy spectrum between ~90 GeV and 500 GeV is well described by a power law with photon index Gamma = 4.2 +- 0.3. The combined 2005 and 2006 energy spectrum provides an upper limit of z=0.74 on the redshift of the object.

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J. Albert et al.. 2007-04-19. Detection of VHE radiation from the BL Lac PG 1553+113 with the MAGIC telescope. https://doi.org/10.1086/511384

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