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تسجيل مستخدم جديدDiscovery of high and very high-energy emission from the BL Lac object SHBL J001355.9-185406
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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$<$E$<$300 GeV) and very high-energy (VHE; $E>100,{rm GeV}$) 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 $5.5,sigma$ significance level. The measured flux above 310 GeV is $(8.3 pm 1.7_{rm{stat}}pm 1.7_{rm{sys}})times 10^{-13}$ 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 $5.5,sigma$ significance level, with an integrated flux above 300 MeV of $(9.3 pm 3.4_{rm stat} pm 0.8_{rm sys})times 10^{-10}$ photons cms and a photon index of $Gamma = 1.96 pm 0.20_{rm stat} pm 0.08_{rm sys}$. X-ray observations with textit{Swift}-XRT allow the synchrotron peak energy in $ u F_ u$ representation to be located at $sim 1.0,{rm keV}$. 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.
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