199 citations · 2.3k across the 50 of their papers we have counts for
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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…
First detection of VHE gamma-ray signal from the FSRQ TON 0599
MAGIC Collaboration, K. Abe, S. Abe +245
TON\,0599 (z=0.7247) belongs to the few flat spectrum radio quasars (FSRQs) detected in the very high energy (VHE, \,GeV) gamma-ray band. Its redshift makes it currently o…
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…
Multiband Optical Variability of the Blazar 3C 454.3 on Diverse Timescales
Karan Dogra, Alok C. Gupta, C. M. Raiteri +79
Due to its peculiar and highly variable nature, the blazar 3C 454.3 has been extensively monitored by the WEBT team. Here, we present for the first time these long-term optical flu…
Multi-wavelength picture of the misaligned BL Lac object 3C 371
J. Otero-Santos, C. M. Raiteri, A. Tramacere +52
The BL Lac object 3C 371 is one of the targets that are regularly monitored by the Whole Earth Blazar Telescope (WEBT) Collaboration to study blazar variability on both short and l…
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…
Optical variability of the blazar 3C 371: from minute to year timescales
J. Otero-Santos, C. M. Raiteri, J. A. Acosta-Pulido +41
The BL Lac object 3C 371 has been observed by the Transiting Exoplanet Survey Satellite (\textit{TESS}) for approximately a year, between July 2019 and July 2020, with an unmatched…
The variability patterns of the TeV blazar PG 1553+113 from a decade of MAGIC and multi-band observations
MAGIC Collaboration, H. Abe, S. Abe +264
PG 1553+113 is one of the few blazars with a convincing quasi-periodic emission in the gamma-ray band. The source is also a very high-energy (VHE; >100 GeV) gamma-ray emitter. To b…
Extreme photometric and polarimetric variability of blazar S4 0954+65 at its maximum optical and -ray brightness levels
C. M. Raiteri, M. Villata, M. I. Carnerero +64
In 2022 the BL Lac object S4 0954+65 underwent a major variability phase, reaching its historical maximum brightness in the optical and -ray bands. We present optical photometri…
Multi-year characterisation of the broad-band emission from the intermittent extreme BL Lac 1ES~2344+514
H. Abe, S. Abe, V. A. Acciari +232
The BL Lac 1ES 2344+514 is known for temporary extreme properties (e.g., a shift of the synchrotron SED peak energy above 1keV). While those extreme states were so fa…
The optical behaviour of BL Lacertae at its maximum brightness levels: a blend of geometry and energetics
C. M. Raiteri, M. Villata, S. G. Jorstad +13
In 2021 BL Lacertae underwent an extraordinary activity phase, which was intensively followed by the Whole Earth Blazar Telescope (WEBT) Collaboration. We present the WEBT optical…
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…
Investigation of the correlation patterns and the Compton dominance variability of Mrk 421 in 2017
MAGIC Collaboration, V. A. Acciari, S. Ansoldi +284
We present a detailed characterisation and theoretical interpretation of the broadband emission of the paradigmatic TeV blazar Mrk 421, with special focus on the multi-band flux co…
The complex variability of blazars: Time-scales and periodicity analysis in S4 0954+65
C. M. Raiteri, M. Villata, V. M. Larionov +3
Among active galactic nuclei, blazars show extreme variability properties. We here investigate the case of the BL Lac object S4 0954+65 with data acquired in 2019-2020 by the Trans…
The dual nature of blazar fast variability. Space and ground observations of S5 0716+714
C. M. Raiteri, M. Villata, D. Carosati +39
Blazar S5 0716+714 is well-known for its short-term variability, down to intra-day time-scales. We here present the 2-min cadence optical light curve obtained by the TESS space tel…
The Great Markarian 421 Flare of February 2010: Multiwavelength variability and correlation studies
A. U. Abeysekara, W. Benbow, R. Bird +256
We report on variability and correlation studies using multiwavelength observations of the blazar Mrk 421 during the month of February, 2010 when an extraordinary flare reaching a…
Unravelling the complex behavior of Mrk 421 with simultaneous X-ray and VHE observations during an extreme flaring activity in April 2013
MAGIC collaboration, V. A. Acciari, S. Ansoldi +237
We report on a multi-band variability and correlation study of the TeV blazar Mrk 421 during an exceptional flaring activity observed from 2013 April 11 to 2013 April 19. The study…
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…
Optical Variability of the TeV Blazar 1ES 0806+524 on Diverse Timescales
Ashwani Pandey, Alok C. Gupta, Sofia O. Kurtanidze +14
We report the results of our optical (VRI) photometric observations of the TeV blazar 1ES 0806524 on 153 nights during 2011-2019 using seven optical telescopes in Europe and Asi…
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…
Optical Variability of TeV Blazars on long time-scales
Haritma Gaur, Alok C. Gupta, R. Bachev +12
We present the results of photometric observations of three TeV blazars, 3C 66A, S5 0954+658 and BL Lacertae, during the period 2013--2017. Our extensive observations were performe…
The extreme HBL behaviour of Markarian 501 during 2012
M. L. Ahnen, S. Ansoldi, L. A. Antonelli +276
A multiwavelength campaign was organized to take place between March and July of 2012. Excellent temporal coverage was obtained with more than 25 instruments, including the MAGIC,…
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-…