相关论文: Exploring the nature of broadband variability in t…
We performed a long-term optical (B, V, R bands), infra-red (J and K bands) and radio band (15, 22, 37 GHz band) study on the flat spectrum radio quasar, 3C 454.3, using the data collected over a period of more than 8 years (MJD…
We present the results of extensive multi-waveband monitoring of the blazar 3C~279 between 1996 and 2007 at X-ray energies (2-10 keV), optical R band, and 14.5 GHz, as well as imaging with the Very Long Baseline Array (VLBA) at 43 GHz. In…
Violent multi-wavelength variabilities are observed in gamma-ray-selected blazars. We present an analysis of long-term light curves for eight bright blazars to explore the co-variation pattern in the gamma-ray and radio bands. We extract…
We present the results of our study of cross-correlations between long-term multi-band observations of the radio variability of the blazar 3C 279. More than a decade (2008-2022) of radio data were collected at seven different frequencies…
We present an update of 3C 273's database hosted by the ISDC, completed with data from radio to gamma-ray observations over the last 10 years. We use this large data set to study the multiwavelength properties of this quasar,especially…
We analyze X-ray light curves of the blazars Mrk 421, PKS 2155-304, and 3C 273 using observations by the Soft X-ray Telescope on board AstroSat and archival XMM-Newton data. We use light curves of length 30-90 ks each from 3-4 epochs for…
A multiwavelength temporal and spectral analysis of flares of 3C 279 during November 2017--July 2018 are presented in this work. Three bright gamma-ray flares were observed simultaneously in X-ray and Optical/UV along with a prolonged…
We present a \gamma-ray photon flux and spectral variability study of the flat-spectrum radio quasar 3C 273 over a rapid flaring activity period between September 2009 to April 2010. Five major flares are observed in the source during this…
The X-ray emission from quasars such as 3C273 is generally agreed to arise from Compton scattering of low energy seed photons by relativistic electrons in a relativistic jet oriented close to the line of sight. However there are a number of…
The flat-spectrum radio quasar 3C~454.3 throughout the years has presented very high activity phases (flares) in which the different wavebands increase their flux dramatically. In this work, we perform multiwavelength analysis from radio to…
We have undertaken a nearly simultaneous optical/UV and X-ray variability study of the flat spectrum radio quasar, 3C 273 using data available from the XMM$-$Newton satellite mission from June 2000 to July 2012. Here we focus on the…
Blazars exhibit relentless variability across diverse spatial and temporal frequencies. The study of long- and short-term variability properties observed in the X-ray band provides insights into the inner workings of the central engine. In…
We investigate the short-term variability properties and the power spectral density (PSD) of the Broad-Line Radio Galaxy (BLRG) 3C 390.3 using observations made by XMM, RXTE, and Suzaku on several occasions between October 2004 and December…
We report the results of decade-long (2008-2018) $\gamma$-ray to 1 GHz radio monitoring of the blazar 3C 279, including GASP/WEBT, $\it{Fermi}$ and $\it{Swift}$ data, as well as polarimetric and spectroscopic data. The X-ray and…
The blazar 3C 454.3 was revealed by the Fermi Gamma-ray Space Telescope to be in an exceptionally high flux state in July 2008. Accordingly, we performed a multi-wavelength monitoring campaign on this blazar using IR and optical…
We present a detailed temporal and spectral analysis of the blazar S5\,1044+71 using multi-wavelength data obtained from the \emph{Fermi}-LAT and Swift-XRT/UVOT telescopes. Applying the Bayesian block algorithm to the 3-day binned…
In spring 2005 the blazar 3C 454.3 was observed in an unprecedented bright state from the near-IR to the hard X-ray frequencies. A mm outburst peaked in June-July 2005, and it was followed by a flux increase at high radio frequencies. In…
Due to its powerful radiation over the entire electromagnetic spectrum and its radio jet activity, the blazar 3C273 offers the opportunity to study the physics of $\gamma$-ray emission from active galactic nuclei. Since a historically…
We present multiwavelength light curves and polarimetric data of the Flat Spectrum Radio Quasar 3C 273 over 8 years. The wavelength range of our data set extends from radio to gamma-rays. We found that the optical emission in this source is…
Characterisation of the long-term variations in the broad line region in a luminous blazar, where Comptonisation of broad-line emission within a relativistic jet is the standard scenario for production of gamma-ray emission that dominates…