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arXiv · 1912.07273

Simultaneous observations of the blazar PKS2155-304 from Ultra-Violet to TeV energies

H. E. S. S.·Fermi·NuSTAR collaborations
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Abstract

The results of the first ever contemporaneous multi-wavelength observation campaign on the BL Lac object PKS2155-304 involving Swift, NuSTAR, Fermi-LAT and H.E.S.S. are reported. The use of these instruments allows us to cover a broad energy range, important for disentangling the different radiative mechanisms. The source, observed from June 2013 to October 2013, was found in a low flux state with respect to previous observations but exhibited highly significant flux variability in the X-rays. The high-energy end of the synchrotron spectrum can be traced up to 40 keV without significant contamination by high-energy emission. A one-zone synchrotron self-Compton model was used to reproduce the broadband flux of the source for all the observations presented here but failed for previous observations made in April 2013. A lepto-hadronic solution was then explored to explain these earlier observational results.

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H. E. S. S., Fermi, NuSTAR collaborations. 2019-12-16. Simultaneous observations of the blazar PKS2155-304 from Ultra-Violet to TeV energies. https://doi.org/10.1051/0004-6361%2F201936900

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