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The 2010 very high energy γ-ray flare and 10 years of multi-wavelength observations of M 87
(IOP Publishing, 2012)
The giant radio galaxy M 87 with its proximity (16 Mpc), famous jet, and very massive black hole ((3 – 6) × 109 M☉) provides a unique opportunity to investigate the origin of very high energy (VHE; E > 100 GeV) γ-ray ...
Gamma-gamma absorption in the broad line region radiation fields of gamma-ray blazars
(IOP Publishing, 2016)
The expected level of γγ absorption in the Broad Line Region (BLR) radiation field of γ-ray loud Flat Spectrum Radio Quasars (FSRQs) is evaluated as a function of the location of the γ-ray emission region. This is done ...
On the minimum jet power of TeV BL Lac Objects in the p–γ model
(IOP Publishing, 2019)
We study the requirement of the jet power in the conventional p–γ models (photopion production and Bethe–
Heitler pair production) for TeV BL Lac objects. We select a sample of TeV BL Lac objects whose spectral ...
Testing two-component models on very high-energy gamma-ray-emitting BL Lac objects
(EDP Sciences, 2020)
Context. It has become evident that one-zone synchrotron self-Compton models are not always adequate for very high-energy (VHE) gamma-ray-emitting blazars. While two-component models perform better, they are difficult to ...
The ablation of gas clouds by blazar jets
(EDP Sciences, 2020)
Context. Flaring activity in blazars can last for vastly different timescales, and it may be the result of density enhancements in the jet flow that result from the intrusion of an interstellar cloud into the jet.
Aims. ...
Probing the emission mechanism and magnetic field of neutrino blazars with multiwavelength polarization signatures
(IOP Publishing, 2019)
The characteristic two-component blazar spectral energy distribution (SED) can be of either leptonic and/or hadronic origins. The potential association of the high-energy neutrino event IceCube-170922A with the flaring ...
Cascading constraints from neutrino-emitting blazars: the case of TXS 0506+056
(IOP Publishing, 2019)
We present a procedure to generally constrain the environments of neutrino-producing sites in photomeson production models of jetted active galactic nuclei (AGNs) where any origin of the dominant target photon field can ...
Characterizing the γ-ray long-term variability of PKS 2155-304 with H.E.S.S. and Fermi-LAT
(EDP Sciences, 2017)
Studying the temporal variability of BL Lac objects at the highest energies provides unique insights into the extreme physical processes occurring in relativistic jets and in the vicinity of super-massive black holes. To ...
EBL inhomogeneity and hard-spectrum gamma-ray sources
(IOP Publishing, 2017)
The unexpectedly hard very-high-energy (VHE; E > 100 GeV) γ-ray spectra of a few distant blazars have been interpreted as evidence of a reduction of the γγ opacity of the universe due to the interaction of VHE γ-rays with ...
H.E.S.S. discovery of very high energy γ-ray emission from PKS 0625−354
(Oxford Univ Press, 2018)
PKS 0625−354 (z = 0.055) was observed with the four High Energy Stereoscopic System (H.E.S.S.) telescopes in 2012 during 5.5 h. The source was detected above an energy threshold of 200 GeV at a significance level of 6.1σ. ...