相关论文: Magnetic Field Amplification and Flat Spectrum Rad…
Recent multiwavelength observations of PKS 0208-512 by SMARTS, Fermi, and Swift revealed that gamma-ray and optical light curves of this flat spectrum radio quasars are highly correlated, but with an exception of one large optical flare…
The flat spectrum radio quasar (FSRQ) PKS 0208-512 underwent three outbursts at the optical-near-infrared (OIR) wavelengths during 2008-2011. The second OIR outburst did not have a gamma-ray counterpart despite being comparable in…
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 current…
Blazars are known to show flux variations over a range of energies from low energy radio to high energy gamma-rays. Cross-correlation analysis of the optical and $\gamma$-ray light curves in blazars shows that flux variations are generally…
A prediction for the energy shift of the synchrotron spectrum of flat-spectrum radio quasars (FSRQs) during high-energy flares is presented. If the $\gamma$-ray emission of FSRQs is produced by Comptonization of external radiation, then the…
The gamma-ray emission offers a powerful diagnostic tool to probe jets and their surroundings in flat spectrum radio quasars (FSRQ). In particular, sources emitting at high energies (>10 GeV) give us the strongest constraints. This…
Context. The origin of blazar variability, seen from radio up to gamma rays, is still a heavily debated matter and broadband flares offer a unique testbed towards a better understanding of these extreme objects. Such an energetic outburst…
We present the results from the Suzaku X-ray observations of five flat-spectrum radio quasars (FSRQs), namely PKS0208-512, Q0827+243, PKS1127-145, PKS1510-089 and 3C 454.3. All these sources were additionally monitored simultaneously or…
Blazar subclasses ranging from flat-spectrum radio quasars (FSRQs) through low-frequency-peaked BL Lac objects (LBLs) to high-frequency-peaked BL Lac objects (HBLs) exhibit a sequence of increasing spectral hardness with decreasing…
In this paper, we discuss the light-curve features of various flaring scenarios in a time-dependent leptonic model for low-frequency-peaked blazars. The quasar 3C273 is used as an illustrative example. Our code takes into account Fermi-II…
We present a multi-wavelength study of the Flat Spectrum Radio Quasar PKS 1222+216, analyzing its long-term variability of radio data obtained in 2013-2020 from the iMOGABA, MOJAVE, and VLBA-BU-BLAZAR programs, along with $\gamma$-ray data…
We study particle acceleration and radiative processes in Blazar jets under recurring conditions set by gravitational perturbations in supermassive binary systems. We consider the action from a companion orbiting a primary black hole of…
Blazar jets are renowned for their rapid violent variability and multiwavelength flares, however, the physical processes responsible for these flares are not well understood. In this paper we develop a time-dependent inhomogeneous fluid jet…
The evolution of the spectral energy distribution during flares constrains models of particle acceleration in blazar jets. The archetypical blazar BL Lac provided a unique opportunity to study spectral variations during an extended strong…
Study of the polarization behaviour in blazars is a powerful tool to discern the role of magnetic field in the variable emission process in their relativistic jets. We present here results of our systematic investigation on the correlation…
Using fully relativistic GEANT4 simulation tool kit, the transport of energetic electrons generated in solar flares was Monte-Carlo simulated, and resultant bremsstrahlung gamma-ray spectra were calculated. The solar atmosphere was…
We present the temporal and spectral study of blazar PKS 0208-512, using recent flaring activity from November 2019 to May 2020, as detected by the Fermi-LAT observatory. The contemporaneous X-ray, optical/UV observations from…
The flat spectrum radio quasar PKS 1510-089 is one of the most active blazars in $\gamma$-rays, exhibiting phases of very high activity. This study investigates its variability over a decade across a wide range of wavelengths, from radio to…
Simultaneous observations of blazars in different spectral regimes imply that the amplitude of variability depends on the observational band. Both in the low energy spectral component and in the high energy spectral component, the amplitude…
In this work I review the observational constraints imposed on the energetics and magnetisation of quasar jets, in the context of theoretical expectations. The discussion is focused on issues regarding the jet production efficiency, matter…