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Long-term X-ray variability characteristics of the narrow-line Seyfert 1 galaxy RE J1034+396
(Oxford Univ Press, 2018)
We present the results of our study of the long-term X-ray variability characteristics of the narrow-line Seyfert 1 galaxy RE J1034+396. We use data obtained from the AstroSat satellite along with light curves obtained ...
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. ...
Optical variability in IBL S5 0716+714 during the 2013-2015 outbursts
(IOP Publishing, 2018)
With an aim to explore optical variability at diverse timescales in BL Lac source S5 0716+714, it was observed for 46 nights during 2013 January 14 to 2015 June 01 when it underwent two major outbursts. The observations ...
A hard gamma-ray flare from 3C 279 in 2013 December
(IOP, 2016)
The blazar 3C 279 exhibited twin γ-ray flares of similar intensity in 2013 December and 2014 April. In this work, we present a detailed multi-wavelength analysis of the 2013 December flaring event. Multi-frequency observations ...
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 ...
Gravitational light-bending prevents γγ absorption in gravitational lenses
(EDP Sciences, 2016)
The magnification effect that is due to gravitational lensing enhances the chances of detecting moderate-redshift (z ~ 1) sources in very high-energy (VHE; E > 100 GeV) γ-rays by ground-based atmospheric Cherenkov telescope ...
Scaling of relativistic shear flows with the bulk Lorentz factor
(IOP Publishing, 2018)
We compare Particle-in-cell simulation results of relativistic electron–ion shear flows with different bulk Lorentz factors,
and discuss their implications for spine-sheath models of blazar versus gamma-ray burst (GRB) ...
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 ...
Discovery of a suspected giant radio galaxy with the KAT-7 array
(Oxford Univ Press, 2016)
We detect a new suspected giant radio galaxy (GRG) discovered by KAT-7. The GRG core is identified with the Wide-field Infrared Survey Explorer source J013313.50-130330.5, an extragalactic source based on its infrared ...
Multiwavelength study of quiescent states of Mrk 421 with unprecedented hard x-ray coverage provided by NuSTAR in 2013
(IOP Publishing, 2016)
We present coordinated multiwavelength observations of the bright, nearby BL Lacertae object Mrk 421 taken in 2013 January–March, involving GASP-WEBT, Swift, NuSTAR, Fermi-LAT, MAGIC, VERITAS, and other collaborations and ...