199 citations · 666 across the 30 of their papers we have counts for
30 papers
Intraday Optical Variability of BL Lacertae during its Highly Active 2020-2024 Phase
A. Takey, Ergün Ege, B. M. Mihov +12
We present an analysis of the intraday flux and spectral variability of BL Lacertae from 2020 September 30 to 2024 December 7, covering its highest recorded brightness and low, int…
GRB 241030A: a bright afterglow challenging forward shock emission
J. -G. Ducoin, C. Pellouin, V. Aivazyan +97
Gamma-Ray Burst GRB 241030A (z = 1.411) exhibited a bright afterglow (similar to GRB 221009A), detected across gamma-ray, X-ray, UV, and optical bands, providing a probe of GRB aft…
Multi-epoch afterglow rebrightenings in GRB 250129A: Evidence for successive shock interactions
D. Akl, S. Antier, H. Koehn +105
Most long gamma-ray bursts (GRBs) exhibit afterglows broadly consistent with external forward-shock emission, typically described by smooth broken power-law decays in the multiband…
Multiband optical variability on diverse timescales of the blazar Ton 599 from 2011 to 2023
O. Vince, C. M. Raiteri, M. Villata +72
(Shortened)Context: We analyze the optical variability of the FSRQ Ton 599 using BVRI photometry from the WEBT collaboration (2011-2023), complemented by photometric and spectrosco…
Multi-wavelength variability analysis of the blazar S5 0716+714 during a long-lasting period of low activity
B. M. Mihov, E. G. Elhosseiny, L. S. Slavcheva-Mihova +3
We conducted a multi-wavelength monitoring campaign of the blazar S5 0716+714 from 2022 November 26 to 2023 May 28 using optical telescopes in Egypt and Bulgaria. Data were taken d…
A wiggling filamentary jet at the origin of the blazar multi-wavelength behaviour
C. M. Raiteri, M. Villata, M. I. Carnerero +96
Blazars are beamed active galactic nuclei known for their strong multi-wavelength variability on timescales from years down to minutes. We aim to investigate the suitability of the…
Multi-band analyses of the bright GRB 230812B and the associated SN2023pel
T. Hussenot-Desenonges, T. Wouters, N. Guessoum +109
GRB~230812B is a bright and relatively nearby () long gamma-ray burst (GRB) that has generated significant interest in the community and has thus been observed over the en…
Analysis of the intra-night variability of BL Lacertae during its August 2020 flare
Aditi Agarwal, B. Mihov, Vipul Agrawal +7
We present an analysis of the photometry of the blazar BL Lacertae on diverse timescales from mid-July to mid-September 2020. We have used 11 different optical telescopes ar…
Polarimetric Reverberation Mapping in Medium-Band Filters
Elena Shablovinskaya, Luka Č. Popović, Roman Uklein +8
Earlier, we suggested the "reload" concept of the polarimetric reverberation mapping of active galactic nuclei (AGN), proposed for the first time more than 10 years ago. We have su…
Multi-band behaviour of the TeV blazar PG 1553+113 in optical range on diverse timescales
A. Agarwal, B. Mihov, I. Andruchow +11
Context. The TeV BL Lac object PG 1553+113 is one of the primary candidates for a binary supermassive black hole system. Aims. We study the flux and spectral variability of PG 1553…
Multiwavelength behaviour of the blazar 3C279: decade-long study from -ray to radio
V. M. Larionov, S. G. Jorstad, A. P. Marscher +84
We report the results of decade-long (2008-2018) -ray to 1 GHz radio monitoring of the blazar 3C 279, including GASP/WEBT, and data, as well as polarim…
Investigating the multiwavelength behaviour of the flat spectrum radio quasar CTA 102 during 2013-2017
F. D'Ammando, C. M. Raiteri, M. Villata +94
We present a multiwavelength study of the flat-spectrum radio quasar CTA 102 during 2013-2017. We use radio-to-optical data obtained by the Whole Earth Blazar Telescope, 15 GHz dat…
The beamed jet and quasar core of the distant blazar 4C 71.07
C. M. Raiteri, M. Villata, M. I. Carnerero +5
The object 4C 71.07 is a high-redshift blazar whose spectral energy distribution shows a prominent big blue bump and a strong Compton dominance. We present the results of a two-yea…
Multi-band optical variability of 3C 279 on diverse timescales
Aditi Agarwal, Sergio A. Cellone, Ileana Andruchow +8
We have monitored the flat spectrum radio quasar, 3C 279, in the optical , , and passbands from 2018 February to 2018 July for 24 nights, with a total of 716 frames,…
AGILE, Fermi, Swift, and GASP-WEBT multi-wavelength observations of the high-redshift blazar 4C 71.07 in outburst
S. Vercellone, P. Romano, G. Piano +56
The flat-spectrum radio quasar 4C 71.07 is a high-redshift (), -loud blazar whose optical emission is dominated by the thermal radiation from accretion disc. 4C 7…
A Study of the High-Luminosity Quasar HS 1946+7658
B. Mihov, L. Slavcheva-Mihova
We study the variability of the quasar HS 1946+7658 on intra-night time scale based on both our own optical and archival X-ray data. We find the quasar non-variable during about 11…
Blazar spectral variability as explained by a twisting inhomogeneous jet
C. M. Raiteri, M. Villata
Blazar emission is dominated by non-thermal radiation from a relativistic jet pointing toward us, therefore undergoing Doppler beaming. This is responsible for flux enhancement and…
Dissecting the long-term emission behaviour of the BL Lac object Mrk 421
M. I. Carnerero, C. M. Raiteri, M. Villata +4
We report on long-term multi-wavelength monitoring of blazar Mrk 421 by the GASP-WEBT collaboration and Steward Observatory, and by the Swift and Fermi satellites. We study the sou…
Synchrotron emission from the blazar PG 1553+113. An analysis of its flux and polarization variability
C. M. Raiteri, F. Nicastro, A. Stamerra +4
In 2015 July 29 - September 1 the satellite XMM-Newton pointed at the BL Lac object PG 1553+133 six times, collecting data for 218 hours. During one of these epochs, simultaneous o…
Nature of Intra-night Optical Variability of BL Lacertae
Haritma Gaur, Alok C. Gupta, R. Bachev +13
We present the results of extensive multi-band intra-night optical monitoring of BL Lacertae during 2010--2012. BL Lacertae was very active in this period and showed intense variab…
3C 273 - half a century later
L. Slavcheva-Mihova, B. Mihov, I. Iliev
We have presented an optical monitoring of 3C 273, the first quasar discovered fifty years ago. It does not show variability both on intra-night and long-term time scales. To facil…
Optical Flux and Spectral Variability of Blazars
Haritma Gaur, Alok C. Gupta, A. Strigachev +9
We report the results of optical monitoring for a sample of 11 blazars including 10 BL Lacs and 1 Flat Spectrum Radio Quasar (FSRQ). We have measured the multiband optical flux and…
NPM1G -10.0586: an emission-line companion of the Seyfert galaxy Mrk 509
Lyuba Slavcheva-Mihova, Boyko Mihov
We report spectral observations of the galaxy NPM1G -10.0586, the main candidate-companion of Mrk 509. Mrk 509 is a Seyfert galaxy showing no evidence of morphological perturbation…
Young Exoplanet Transit Initiative (YETI)
R. Neuhäuser, R. Errmann, A. Berndt +80
We present the Young Exoplanet Transit Initiative (YETI), in which we use several 0.2 to 2.6m telescopes around the world to monitor continuously young (< 100 Myr), nearby (< 1 kpc…