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AGN observations with a less than 100 GeV threshold using H.E.S.S. II

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 نشر من قبل Dmitry Zaborov
 تاريخ النشر 2015
  مجال البحث فيزياء
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The recent addition of the 28 m Cherenkov telescope (CT5) to the H.E.S.S. array extended the experiments sensitivity towards low energies. The lowest energy threshold is obtained using monoscopic observations with CT5, providing access to gamma-ray energies below 100 GeV. This is particularly beneficial for studies of Active Galactic Nuclei (AGN) with soft spectra and located at redshifts >= 0.5. Stereoscopic measurements with the full array (CT1-5) provide a better background rejection than CT5 Mono, at a cost of a higher threshold. We report on the analysis employing the CT5 data for AGN observations with a < 100 GeV threshold. In particular, the spectra of PKS 2155-304 and PG 1553+113 are presented.



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