activity
20072026
most citedIntra-night optical flux and polarization variability of BL~Lacertae during its 2020 2021 high state

23 citations · 131 across the 21 of their papers we have counts for

collaborators

22 papers

astro-ph.HE2026

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…

astro-ph.SR2025★ 2 cited

Polarimetric and spectropolarimetric observations with FoReRo2: Instrument overview and standard star monitoring

Yanko Nikolov, Galin Borisov, Stefano Bagnulo +3

In this paper, we present a description and characterisation of the 2-Channel Focal Reducer Rozhen (FoReRo2), with an emphasis on its polarimetric and spectropolarimetric observati…

astro-ph.HE2025

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…

astro-ph.SR2024★ 3 cited

Evolution of the optical emission lines and the X-ray emission during the super-active stage of T CrB

K. A. Stoyanov, G. J. M. Luna, R. K. Zamanov +6

T CrB is a symbiotic star that experiences nova outbursts every 80~yr. The next, long-anticipated nova outburst should occur during the 2024-2026 period. Here, we present re…

astro-ph.SR2023★ 5 cited

Transient and asymmetric dust structures in the TeV-bright nova RS Oph revealed by spectropolarimetry

Y. Nikolov, G. J. M. Luna, K. A. Stoyanov +4

A long-standing question related to nova eruptions is how these eruptions can lead to the formation of dust despite the ostensibly inhospitable environment for dust within the hot,…

astro-ph.HE2023★ 23 cited

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…