17 papers
Multi-band optical photometric variability of the blazar OJ 287 from 2015 to 2025
Alok C. Gupta, Karan Dogra, Mark Kidger +101
We present the most densely sampled multi-band optical photometric observations of the peculiar BL Lacertae object OJ 287 from 2015 to 2025 with a focus on its optical activity on…
Detection of Quasiperiodic Oscillations in the Blazar PKS 0735+178 with TESS
Shubham Kishore, Alok C. Gupta, Paul J. Wiita +2
We report here the detection of signatures of a quasiperiodic oscillation (QPO) and a short flare in the optical light curve of the blazar PKS 0735+178, observed in two sectors, 71…
Simulating megaparsec-scale jets of radio galaxies: Magneto-hydrodynamics of jets reaching 5 Mpc
Gourab Giri, Dario Borgogno, Marco Tavani +9
Extragalactic jets have long prompted the question of how far relativistic outflows can extend, with some radio sources reaching 5 - 7 Mpc in length. These great extents motivate i…
Origin of the double-peaked narrow emission-lines in the optical spectra of X-shaped Radio Galaxies
Ghosh Prajnadipt, Ravi Joshi, Xiaolong Yang +13
We investigate X-shaped radio galaxies (XRGs) with optical double-peaked narrow emission lines (DPNELs) as potential hosts of dual or binary supermassive black holes (SMBHs). Using…
Detection of optical quasi-periodic oscillation in the blazar 3C 454.3
Karan Dogra, Alok C. Gupta, C. M. Raiteri +83
We analyzed 19 years of -band data of the blazar 3C 454.3 from the Whole Earth Blazar Telescope (WEBT) archive, along with new data from its members and from public archives suc…
X-Ray Spectral Variability of the TeV HBL Blazar PG 1553+113 with XMM-Newton
P. U. Devanand, Alok C. Gupta, Paul J. Wiita +2
We present an extensive X-ray spectral variability study of the TeV photon-emitting high-energy-peaked BL Lacertae object PG 1553+113, using the data from EPIC-PN camera of XMM-New…