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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. ...
Opacities for photon splitting and pair creation in neutron star magnetospheres
(Oxford Univ Press, 2019)
Over the last four decades, persistent and flaring emission of magnetars observed by various telescopes has provided us with a suite of light curves and spectra in soft and hard X-rays, with no emission yet detected above ...
H.E.S.S. and Suzaku observations of the Vela X pulsar wind nebula
(EDP Sciences, 2019)
Context. Pulsar wind nebulae (PWNe) represent the most prominent population of Galactic very-high-energy gamma-ray sources and are thought to be an efficient source of leptonic cosmic rays. Vela X is a nearby middle-aged ...
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 ...
First ground-based measurement of sub-20 GeV to 100GeV y-Rays from the Vela pulsar with H.E.S.S. II
(EDP Sciences, 2018)
Aims. We report on the measurement and investigation of pulsed high-energy γ-ray emission from the Vela pulsar, PSR B0833−45, based on observations with the largest telescope of H.E.S.S., CT5, in monoscopic mode, and on ...
The y-ray spectrum of the core of Centaurus A as observed with H.E.S.S. and Fermi-LAT
(EDP Sciences, 2018)
Centaurus A (Cen A) is the nearest radio galaxy discovered as a very-high-energy (VHE; 100 GeV–100 TeV) γ-ray source by the High Energy Stereoscopic System (H.E.S.S.). It is a faint VHE γ-ray emitter, though its VHE flux ...
Relativistic jets in active galactic nuclei and microquasars
(Springer, 2017)
Collimated outflows (jets) appear to be a ubiquitous phenomenon associated with the accretion of material onto a compact object. Despite this ubiquity, many fundamental physics aspects of jets are still poorly understood ...
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 ...