155 citations · 4.2k across the 161 of their papers we have counts for
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Multi-band Optical Variability of the TeV Blazar PG 1553+113 in 2019
Vinit Dhiman, Alok C. Gupta, Sofia O. Kurtanidze +20
We report the flux and spectral variability of PG 1553+113 on intra-night (IDV) to short-term timescales using BVRI data collected over 91 nights from 28 February to 8 November 201…
Detection of Quasi-Periodic Oscillations in the Blazar S4 0954+658 with TESS
Shubham Kishore, Alok C. Gupta, Paul J. Wiita
We report the detection of several quasi-periodicities around 0.6--2.5 days in the optical emission of the blazar S4 0954+658. The source was observed by the Transiting Exoplanet S…
Probable low-frequency quasi-periodic oscillations in blazars from the ZTF survey
Anuvab Banerjee, Vibhore Negi, Ravi Joshi +6
We investigate the possible presence of quasi-periodic oscillation (QPO) signals in 2103 blazars from the Zwicky Transient Facility (ZTF) time-domain survey. We detect a low-freque…
X-ray Intraday Variability of HBL Blazars with XMM-Newton
P. U. Devanand, Alok C. Gupta, V. Jithesh +1
We present an extensive study on the X-ray intraday variability of ten TeV-emitting high synchrotron peaked blazars (HBLs): 1ES 0229+200, 1ES 0414+009, PKS 0548-322, 1ES 1101-232,…
The Twin Radio galaxy TRG J104454+354055
Gopal-Krishna, Ravi Joshi, Dusmanta Patra +4
We report observations of a bright dumb-bell system of galaxies () with the upgraded Giant Metrewave Radio Telescope (GMRT), which show that each member of this gravit…
Long Term Multi-band Near Infra-Red Variability of the Blazar OJ 287 during 2007--2021
Alok C. Gupta, Pankaj Kushwaha, L. Carrasco +9
We present the most extensive and well-sampled long-term multi-band near-infrared (NIR) temporal and spectral variability study of OJ 287, considered to be the best candidate binar…