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Nature of intranight optical variability of BL Lacertae
(Oxford University Press, 2015)
We present the results of extensive multiband intranight optical monitoring of BL Lacertae during 2010–2012. BL Lacertae was very active in this period and showed intense variability in almost all wavelengths. We extensively ...
The violent hard X-ray variability of Mrk 421 observed by NuSTAR in 2013 April
(American Astronomical Society, 2015)
The well-studied blazar Markarian 421 (Mrk 421, z = 0.031) was the subject of an intensive multi-wavelength campaign when it flared in 2013 April. The recorded X-ray and very high-energy (E > 100 GeV) γ-ray fluxes are the ...
A self-consistent and time-dependent hybrid blazar emission model
(EDP Sciences, 2015)
Aims. A time-dependent emission model for blazar jets, taking acceleration due to Fermi-I and Fermi-II processes for electrons and
protons as well as all relevant radiative processes self-consistently into account, is ...
Discovery of hard-spectrum y-ray emission from the BL Lacertae object 1ES 0414+009
(EDP Sciences, 2012)
Context. 1ES 0414 + 009 (z = 0.287) is a distant high-frequency-peaked BL Lac object, and has long been considered a likely emitter of very-high-energy (VHE, E > 100 GeV) γ-rays due to its high X-ray and radio flux.
Aims. ...
Discovery of VHE y-ray emission and multi-wavelength observations of the BL Lacertae object 1RXS J101015.9-311909
(EDP Science, 2012)
1RXS J101015.9 − 311909 is a galaxy located at a redshift of z = 0.14 hosting an active nucleus (called AGN) belonging to the class of bright BL Lac objects. Observations at high (HE, E > 100 MeV) and very high (VHE, E > ...
HESS and Fermi-LAT discovery of γ-rays from the blazar 1ES 1312-423
(Oxford Univ Press, 2013)
A deep observation campaign carried out by the High Energy Stereoscopic System (HESS) on Centaurus A enabled the discovery of γ-rays from the blazar 1ES 1312−423, 2° away from the radio galaxy. With a differential flux at ...
Particle diffusion and localized acceleration in inhomogeneous AGN jets. I. Steady-state spectra
(Oxford University Press, 2015)
We study the acceleration, transport, and emission of particles in relativistic jets. Localized stochastic particle acceleration, spatial diffusion, and synchrotron as well as synchrotron self-Compton (SSC) emission are ...
Multi-band implications of external-IC flares
(Elsevier, 2015)
Very fast variability on scales of minutes is regularly observed in Blazars. The assumption that these flares
are emerging from the dominant emission zone of the very high energy (VHE) radiation within the jet
challenges ...
Hadronic models of blazars require a change of the accretion paradigm
(Oxford University Press, 2015)
We study hadronic models of broad-band emission of jets in radio-loud active galactic nuclei, and their implications for the accretion in those sources. We show that the models that account for broad-band spectra of blazars ...
Flux upper limits for 47 AGN observed with H.E.S.S. in 2004-2011
(EDP Sciences, 2014)
Context. About 40% of the observation time of the High Energy Stereoscopic System (H.E.S.S.) is dedicated to studying active galactic nuclei
(AGN), with the aim of increasing the sample of known extragalactic very-high-energy ...