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HESS J1943+213: a candidate extreme BL Lacertae object
(EDP Sciences, 2011)
We report on a newly detected point-like source, HESS J1943+213 located in the Galactic plane. This source coincides with an unidentified hard X-ray source IGR J19443+2117, which was proposed to have radio and infrared ...
The extended flare in CTA 102 in 2016 and 2017 within a hadronic model through cloud ablation by the relativistic jet
(IOP Publishing, 2019)
The flat-spectrum radio quasar CTA 102 (redshift 1.037) exhibited a tremendously bright four-month-long outburst from late 2016 to early 2017. In a previous paper, we interpreted the event as the ablation of a gas cloud ...
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 ...
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 ...
Detection of large-scale Ly α absorbers at large angles to the radio axis of high-redshift radio galaxies using SOAR
(Oxford Univ Press, 2018)
We present an investigation of the properties of the extended Ly α halo and the large-scale
H I absorbing structures associated with five high-redshift radio galaxies at z > 2, using the
Goodman long-slit spectrograph ...
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 ...
Fermi/LAT counterparts of IceCube neutrinos above 100 TeV
(EDP Sciences, 2018)
The IceCube Collaboration has published four years of data and the observed neutrino flux is significantly in excess of the expected atmospheric background. Due to the steeply falling atmospheric background spectrum, events ...
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 ...
Gamma-ray blazar spectra with H.E.S.S. II mono analysis: the case of PKS 2155-304 and PG 1553+113
(EDP Sciences, 2017)
Context. The addition of a 28 m Cherenkov telescope (CT5) to the H.E.S.S. array extended the experiment’s sensitivityto lower energies. The lowest energy threshold is obtained using monoscopic analysis of data taken with ...