Hans Publishers, Astronomy & Astrophysics, (554), p. A72
DOI: 10.1051/0004-6361/201220996
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The detection of the high-frequency peaked BL Lac object (HBL) SHBL J001355.9-185406 ($z$=0.095) at high (HE; 100 MeV$100\,{\rm GeV}$) with the \fer\ Large Area Telescope (LAT) and the High Energy Stereoscopic System (H.E.S.S.) is reported. Dedicated observations have been performed with the H.E.S.S. telescopes, leading to a detection at the $5.5\,σ$ significance level. The measured flux above 310 GeV is $(8.3 ± 1.7_{\rm{stat}}± 1.7_{\rm{sys}})\times 10^{-13}$ photons \cms\ (about 0.6% of that of the Crab Nebula), and the power law spectrum has a photon index of \indexHESS. Using 3.5 years of publicly available \fla\ data, a faint counterpart has been detected in the LAT data at the $5.5\,σ$ significance level, with an integrated flux above 300 MeV of $(9.3 ± 3.4_{\rm stat} ± 0.8_{\rm sys})\times 10^{-10}$ photons \cms\ and a photon index of $Γ = 1.96 ± 0.20_{\rm stat} ± 0.08_{\rm sys}$. X-ray observations with \textit{Swift}-XRT allow the synchrotron peak energy in $ν F_ν$ representation to be located at $∼ 1.0\,{\rm keV}$. The broadband spectral energy distribution is modelled with a one-zone synchrotron self-Compton (SSC) model and the optical data by a black-body emission describing the thermal emission of the host galaxy. The derived parameters are typical for HBLs detected at VHE, with a particle dominated jet. ; Comment: 8 pages, 5 figures