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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. ...
Spatially dependent modelling of pulsar wind nebula G0.9+0.1
(Oxford Univ Press, 2018)
We present results from a leptonic emission code that models the spectral energy distribution of a pulsar wind nebula by solving a Fokker–Planck-type transport equation and calculating inverse Compton and synchrotron ...
Hard spectral tails in magnetars
(Cambridge Univ Press, 2017)
Pulsed non-thermal quiescent emission between 10 keV and around 150 keV has been observed in ~10 magnetars. For inner magnetospheric models of such hard X-ray signals, resonant Compton upscattering of soft thermal photons ...
Very high energy γ-ray observations of the binary PSR B1259-63/SS2883 around the 2007 Periastron
(EDP Sciences, 2009)
Aims. This article presents very-high-energy (VHE; E > 100 GeV) data from the γ-ray binary PSR B1259-63 as taken during the years 2005, 2006 and before as well as shortly after the 2007 periastron passage. These data extend ...
Systematic search for very-high-energy gamma-ray emission from bow shocks of runaway stars
(EDP Sciences, 2018)
Context. Runaway stars form bow shocks by ploughing through the interstellar medium at supersonic speeds and are promising sources of non-thermal emission of photons. One of these objects has been found to emit non-thermal ...
Polarization signatures of relativistic magnetohydrodynamic shocks in the blazar emission region. I. Force-free helical magnetic fields
(IOP, 2016)
The optical radiation and polarization signatures in blazars are known to be highly variable during flaring activities. It is frequently argued that shocks are the main driver of the flaring events. However, the spectral ...
Particle diffusion and localized acceleration in inhomogeneous AGN jets. II. Stochastic variation
(Oxford Univ Press, 2016)
We study the stochastic variation of blazar emission under a 2D spatially resolved leptonic jet model we previously developed. Random events of particle acceleration and injection in small zones within the emission region ...
Leptonic and lepto-hadronic modeling of the 2010 November flare from 3C 454.3
(AAS, 2016)
In this study, we use a one-zone leptonic and a lepto-hadronic model to investigate the multi-wavelength emission and prominent flare of the flat spectrum radio quasar 3C 454.3 in 2010 November. We perform a parameter study ...
Relativistic shear flow between electron-ion and electron-positron plasmas and astrophysical applications
(IOP, 2017)
We present particle-in-cell simulation results of relativistic shear boundary layers between electron–ion and
electron–positron plasmas and discuss their potential applications to astrophysics. Specifically, we find that ...