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Upper limits from HESS active galactic nuclei observations in 2005-2007
(EDP Sciences, 2008)
Aims.Very high energy (VHE; GeV) γ-ray studies were performed for 18 active galactic nuclei (AGN) from a variety of AGN classes.
Methods.VHE observations of a sample of 14 AGN, considered candidate VHE emitters, were ...
Discovery of VHE gamma-rays from the high-frequency-peaked BL Lacertae object RGB J0152+017
(EDP Sciences, 2008)
Aims. The BL Lac object RGB J0152+017 (z=0.080) was predicted to be a very high-energy (VHE; >100 GeV) $\gamma$-ray source, due to its high X-ray and radio fluxes. Our aim is to understand the radiative processes by ...
Multi-wavelength observations of H 2356-309
(EDP Sciences, 2010)
Aims. The properties of the broad-band emission from the high-frequency peaked BL Lac H 2356–309 (z = 0.165) are investigated.
Methods. Very high energy (VHE; E > 100 GeV) observations of H 2356–309 were performed with ...
A multiwavelength view of the flaring state of PKS 2155-304 in 2006
(EDP Sciences, 2012)
Context: Multiwavelength (MWL) observations of the blazar PKS 2155-304 during two weeks in July and August 2006, the period when two exceptional flares at very high energies (VHE, E ≳ 100 GeV) occurred, provide a detailed ...
Leptonic and hadronic modeling of Fermi-detected blazars
(IOP Science, 2013)
We describe new implementations of leptonic and hadronic models for the broadband emission from relativistic jets in active galactic nuclei in a temporary steady state. For the leptonic model, a temporary equilibrium between ...
Radiation and polarization signatures of the 3D multizone time-dependent hadronic blazar model
(IOP Publishing, 2016)
We present a newly developed time-dependent three-dimensional multizone hadronic blazar emission model. By coupling a Fokker–Planck-based lepto-hadronic particle evolution code, 3DHad, with a polarization-dependent radiation ...
Energy loss in intergalactic pair beams: particle-in-cell simulation
(EDP Sciences, 2016)
Aims. The change in the distribution function of electron-positron pair beams determines whether GeV photons can be produced as
secondary radiation from TeV photons. We will discuss the instabilities driven by pair ...
Synchrotron polarization in blazars
(IOP Publishing, 2014)
We present a detailed analysis of time- and energy-dependent synchrotron polarization signatures in a shock-in-jet model for γ-ray blazars. Our calculations employ a full three-dimensional radiation transfer code, assuming ...
Simultaneous observations of PKS 2155-304 with HESS, FERMI, RXTE, and ATOM: spectral energy distributions and variability in a low state
(IOP Publishing, 2009)
We report on the first simultaneous observations that cover the optical, X-ray, and high-energy gamma-ray bands of the BL Lac object PKS 2155–304. The gamma-ray bands were observed for 11 days, between 2008 August 25 and ...
Simultaneous multi-wavelength campaign on PKS 2005-489 in a high state
(EDP Science, 2011)
TeV γ-ray (H.E.S.S.), GeV γ-ray (Fermi/LAT), X-ray (RXTE, Swift), UV (Swift) and optical (ATOM, Swift) bands. This campaign was carried out during a high flux state in the synchrotron regime. The flux in the optical and ...