63 citations · 516 across the 30 of their papers we have counts for
22 papers · 1 filter
Signature of Seyfert-like component in a blazar 3C 273 and its reflection-based explanation
Haritma Gaur, Main Pal, Muhammad S. Anjum +4
We present the results of blazar 3C 273 obtained from simultaneous observations obtained using XMM-Newton and NuSTAR satellites during the period 2015-2019 in five epochs. When the…
Exploring the disc-jet scenario in 3C 273 using simultaneous XMM-Newton and NuSTAR observations
Ashwani Pandey, Santanu Mondal, Paul J. Wiita
Context: 3C 273, a well-studied active galactic nucleus (AGN), displays characteristics of both jetted-AGN and Seyfert galaxies, making it an excellent source to study the disc-jet…
Origin of the broadband emission from the transition blazar B2 1308+326
Ashwani Pandey, Pankaj Kushwaha, Paul J. Wiita +3
Transition blazars exhibit a shift from one subclass to the next during different flux states. It is therefore crucial to study them to understand the underlying physics of blazars…
Investigating the origin of optical flares from the TeV blazar S4 0954+65
Ashwani Pandey, Rumen Bachev, Bozena Czerny +4
Aims. We aim to investigate the extreme variability properties of the TeV blazar S4 0954+65 using optical photometric and polarisation observations carried out between 2017 and 202…
Detection of minute-timescale gamma-ray variability in BL Lacertae by Fermi-LAT
Ashwani Pandey, C. S. Stalin
BL Lacertae, the prototype of the BL Lacertae (BL Lac) category of blazars, underwent a giant ray flare in April 2021. The Large Area Telescope (LAT) onboard the Fermi Gamma-ra…
Study of correlation between optical flux and polarization variations in BL Lac objects
Bhoomika Rajput, Ashwani Pandey, C. S. Stalin +1
Polarized radiation from blazars is one key piece of evidence for synchrotron radiation at low energy, which also shows variations. We present here our results on the correlation a…
Characterizing the optical nature of the blazar S5 1803+784 during its 2020 flare
A. Agarwal, Ashwani Pandey, Aykut Özdönmez +3
We report the results from our study of the blazar S5 1803+784 carried out using the quasi-simultaneous , , , and observations from May 2020 to July 2021 on 122 nights…
Variable mass accretion and failed wind explain changing look phenomena in NGC 1365
Santanu Mondal, Tek P. Adhikari, Krzysztof Hryniewicz +2
Changing look active galactic nuclei (CLAGNs) show complex nature in their X-ray spectral shape and line of sight column density variation. The physical mechanisms responsible for…
Intra-night optical variability monitoring of -ray emitting blazars
K. Subbu Ulaganatha Pandian, A. Natarajan, C. S. Stalin +3
We present the results obtained from our campaign to characterize the intra-night-optical variability properties of blazars detected by the {\it Fermi} Large Area Telescope. This i…
-ray Flux and Spectral Variability of Blazar Ton 599 during Its 2021 Flare
Bhoomika Rajput, Ashwani Pandey
Blazars are known to emit exceptionally variable non-thermal emission over the wide range (from radio to -rays) of electromagnetic spectrum. We present here the results of our $…
Correlation between optical flux and polarization variations in Flat Spectrum Radio Quasars on diverse timescales
Ashwani Pandey, Bhoomika Rajput, C. S. Stalin
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…
Investigation of the correlation patterns and the Compton dominance variability of Mrk 421 in 2017
MAGIC Collaboration, V. A. Acciari, S. Ansoldi +284
We present a detailed characterisation and theoretical interpretation of the broadband emission of the paradigmatic TeV blazar Mrk 421, with special focus on the multi-band flux co…
Breaks in the X-ray spectra of high redshift blazars and the intervening medium
Haritma Gaur, Prashanth Mohan, Ashwani Pandey
The flat spectrum radio quasars (FSRQs) are a sub-class of blazars characterised by prominent optical emission lines and a collimated large-scale jet along the observer line of sig…
NuSTAR View of TeV Blazar Mrk 501
Ashwani Pandey
We report the results of flux and spectral variability studies of all seven {\it Nuclear Spectroscopic Telescope Array (NuSTAR)} observations of TeV ray emitting blazar Markari…
Optical Variability of Three Extreme TeV Blazars
Ashwani Pandey, Alok C. Gupta, G. Damljanovic +3
We present the results of optical photometric observations of three extreme TeV blazars, 1ES 0229200, 1ES 0414009, and 1ES 2344514, taken with two telescopes (1.3 m Devast…
Optical Variability of the TeV Blazar 1ES 0806+524 on Diverse Timescales
Ashwani Pandey, Alok C. Gupta, Sofia O. Kurtanidze +14
We report the results of our optical (VRI) photometric observations of the TeV blazar 1ES 0806524 on 153 nights during 2011-2019 using seven optical telescopes in Europe and Asi…
Optical Flux and Spectral Variability of the TeV blazar PG 1553+113
Ashwani Pandey, Alok C. Gupta, Paul J. Wiita +1
We present the results of our optical (VRI) observations of the TeV blazar PG 1553+113 over eight nights in 2016 April. We monitored the blazar quasi-simultaneously in V and R band…
X-ray Intraday Variability of the TeV Blazar Mrk 421 with {\it Chandra}
V. Aggrawal, Ashwani Pandey, Alok C. Gupta +4
We present an extensive study of 72 archival Chandra light curves of the high-frequency-peaked type blazar Mrk 421, the first strong extragalactic object to be detected at TeV ener…
X-ray Flux and Spectral Variability of Six TeV Blazars with \textit{NuSTAR}
Ashwani Pandey, Alok C. Gupta, Paul J. Wiita
We report the first results of timing and spectral studies of \textit{Nuclear Spectroscopic Telescope Array (NuSTAR)} observations of six TeV emitting high-frequency peaked blazars…
Characterizing optical variability of OJ 287 in 2016 - 2017
Alok C. Gupta, Haritma Gaur, Paul J. Wiita +22
We report on a recent multi-band optical photometric and polarimetric observational campaign of the blazar OJ 287 which was carried out during September 2016 -- December 2017. We e…
X-ray Intraday Variability of Five TeV Blazars with NuSTAR
Ashwani Pandey, Alok C. Gupta, Paul J. Wiita
We have examined 40 NuSTAR light curves (LCs) of five TeV emitting high synchrotron peaked blazars: 1ES 0229+200, Mrk 421, Mrk 501, 1ES 1959+650 and PKS 2155-304. Four of the blaza…
Multiband optical variability of the blazar OJ 287 during its outbursts in 2015 -- 2016
Alok C. Gupta, A. Agarwal, A. Mishra +31
We present recent optical photometric observations of the blazar OJ 287 taken during September 2015 -- May 2016. Our intense observations of the blazar started in November 2015 and…