45 citations · 239 across the 21 of their papers we have counts for
8 papers · 1 filter
Optical Photometric Monitoring of the Blazar OT 355 and Local Standard Stars' Calibration
R. Bachev, Tushar Tripathi, Alok C. Gupta +11
OT 355 (4FGL J1734.3 + 3858) is a relatively rarely studied but highly variable, moderate-redshift (z = 0.975) flat-spectrum radio quasar (blazar). With this work, we aim to study…
Intra-night optical flux and polarization variability of BL~Lacertae during its 2020 2021 high state
Rumen Bachev, Tushar Tripathi, Alok C. Gupta +15
In this work, we report the presence of rapid intra-night optical variations in both -- flux and polarization of the blazar BL Lacertae during its unprecedented 2020--2021 high sta…
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…
The Bright -ray Flare of 3C 279 in June 2015: AGILE Detection and Multifrequency Follow-up Observations
C. Pittori, F. Lucarelli, F. Verrecchia +44
We report the AGILE detection and the results of the multifrequency follow-up observations of a bright -ray flare of the blazar 3C 279 in June 2015. We use AGILE-GRID and Fermi-…
Intra-night variability of the blazar CTA 102 during its 2012 and 2016 giant outbursts
R. Bachev, V. Popov, A. Strigachev +6
We obtained and analyzed more than 100 hours of multicolour optical time series of the blazar CTA 102 during its 2012 and 2016 outbursts. The object reached almost 11-th mag at the…
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…
The Extremes in Intra-Night Blazar Variability: The S4 0954+65 Case
Rumen Bachev, Anton Strigachev, Evgeni Semkov +4
We present results of optical observations of the extremely violently variable blazar S4 0954+65 on intra-night time scales. The object showed flux changes of up to 100% within a f…
Multi-band optical variability of the Blazar S5 0716+714 in outburst state during 2014-2015
Aditi Agarwal, Alok C. Gupta, R. Bachev +7
We analyzed the multi-band optical behaviour of the BL Lacertae object, S5 0716+714, during its outburst state from 2014 November - 2015 March. We took data on 23 nights at three o…