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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 ...
The awakening of BL Lacertae: observations by Fermi, Swift and the GASP-WEBT
(Oxford University Press, 2013)
Since the launch of the Fermi satellite, BL Lacertae has been moderately active at γ-rays and optical frequencies until 2011 May, when the source started a series of strong flares. The exceptional optical sampling achieved ...
Probing acceleration and turbulence at relativistic shocks in blazar jets
(Oxford Univ Press, 2017)
Diffusive shock acceleration (DSA) at relativistic shocks is widely thought to be an important acceleration mechanism in various astrophysical jet sources, including radio-loud active galactic nuclei such as blazars. Such ...
Possible accretion disk origin of the emission variability of a blazar jet
(IOP Publishing, 2018)
We analyze X-ray light curves of the blazar Mrk 421 obtained from the Soft X-ray Imaging Telescope (SXT) and the Large Area X-ray Proportional Counter (LAXPC) instrument on board the Indian space telescope AstroSat and ...
Attenuation of TeV γ-rays by the starlight photon field of the host galaxy
(Oxford Univ Press, 2017)
The absorption of TeV γ-ray photons produced in relativistic jets by surrounding soft photon fields is a long-standing problem of jet physics. In some cases, the most likely emission site close to the central black hole ...
The 2012 flare of PG 1553+113 seen with H.E.S.S. and Fermi-LAT
(IOP Publishing, 2015)
Very high energy (VHE, E > 100 GeV) γ-ray flaring activity of the high-frequency peaked BL Lac object PG 1553+113 has been detected by the H.E.S.S. telescopes. The flux of the source increased by a factor of 3 during the ...
Monitoring of the radio galaxy M 87 at Very High Energy with MAGIC during a low emission state between 2012 and 2015
(Cambridge Univ Press, 2017)
We present the preliminary results from observing the nearby radio galaxy M 87 for 156 hours (between the years 2012 and 2015) with the MAGIC telescopes, which lead to a significant very high energy (VHE, E > 100 GeV) ...
Radio to gamma-ray variability study of blazar S5 0716+714
(EDP Sciences, 2013)
We present the results of a series of radio, optical, X-ray, and γ-ray observations of the BL Lac object S50716+714 carried out between April 2007 and January 2011. The multifrequency observations were obtained using several ...