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arXiv · 0711.1586

Detection of Very-High Energy Gamma-Rays from the BL Lac Object PG 1553+113 with the MAGIC Telescope

Robert Wagner·Daniela Dorner·Masaaki Hayashida·Thomas Hengstebeck·Daniel Kranich·Daniel Mazin·Diego Tescaro·Nina Nowak
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Abstract

The MAGIC telescope has observed very-high energy gamma-ray emission from the BL Lac object PG 1553+113 in 2005 and 2006 at an overall significance is 8.8 sigma. The light curve shows no significant flux variations on a daily timescale. The flux level during 2005 was, however, significantly higher as compared to 2006. The differential energy spectrum between approx. 90 GeV and 500 GeV is well described by a power law with a spectral index of -4.2+-0.3. The photon energy spectrum and spectral modeling allow to pose upper limits of z=0.74 and z=0.56, respectively, on the yet undetermined redshift of PG 1553+113. Recent VLT observations of this blazar show featureless spectra in the near-IR, thus no direct redshift could be determined from these measurements.

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Robert Wagner, Daniela Dorner, Masaaki Hayashida, Thomas Hengstebeck, Daniel Kranich, Daniel Mazin, Diego Tescaro, Nina Nowak. 2007-11-10. Detection of Very-High Energy Gamma-Rays from the BL Lac Object PG 1553+113 with the MAGIC Telescope. https://arxiv.org/abs/0711.1586

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