activity
20072021
most citedInsights Into the High-Energy Gamma-ray Emission of Markarian 501 from Extensive Multifrequency Observations in the Fermi Era

239 citations · 2.2k across the 31 of their papers we have counts for

collaborators

31 papers

astro-ph.HE2021★ 18 cited

Repeated pattern of gamma-ray flares in the lightcurve of the blazar 3C 279

D. Blinov, S. G. Jorstad, V. M. Larionov +10

The optical polarization plane of some blazars occasionally exhibits smooth hundred degree long rotations. Multiple theoretical models have been proposed to explain the nature of s…

astro-ph.HE2020★ 50 cited

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…

astro-ph.HE2020★ 51 cited

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…

astro-ph.HE2019★ 30 cited

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…

astro-ph.HE2018★ 8 cited

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…

astro-ph.HE2018★ 54 cited

Multi-wavelength characterization of the blazar S5~0716+714 during an unprecedented outburst phase

MAGIC Collaboration, M. L. Ahnen, S. Ansoldi +187

The BL Lac object S5~0716+714, a highly variable blazar, underwent an impressive outburst in January 2015 (Phase A), followed by minor activity in February (Phase B). The MAGIC obs…

astro-ph.HE2018★ 22 cited

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-…

astro-ph.HE2018★ 28 cited

The detection of the blazar S4 0954+65 at very-high-energy with the MAGIC telescopes during an exceptionally high optical state

MAGIC Collaboration, M. L. Ahnen, S. Ansoldi +169

The very-high-energy (VHE, GeV) -ray MAGIC observations of the blazar S4 0954+65, were triggered by an exceptionally high flux state of emission in the optical. Th…

astro-ph.HE2017★ 199 cited

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…

astro-ph.HE2017★ 46 cited

Multi-wavelength temporal and spectral variability of the blazar OJ 287 during and after the December 2015 flare: a major accretion disc contribution

P. Kushwaha, A. C. Gupta, P. J. Wiita +33

We present a multi-wavelength spectral and temporal analysis of the blazar OJ 287 during its recent activity between December 2015 -- May 2016, showing strong variability in the ne…

astro-ph.HE2017★ 47 cited

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…

astro-ph.HE2016★ 67 cited

Multiband variability studies and novel broadband SED modeling of Mrk 501 in 2009

M. L. Ahnen, S. Ansoldi, L. A. Antonelli +290

We present an extensive study of the BL Lac object Mrk 501 based on a data set collected during the multi-instrument campaign spanning from 2009 March 15 to 2009 August 1 which inc…

astro-ph.HE2016★ 58 cited

Exceptional outburst of the blazar CTA 102 in 2012: The GASP-WEBT campaign and its extension

V. M. Larionov, M. Villata, C. M. Raiteri +49

After several years of quiescence, the blazar CTA 102 underwent an exceptional outburst in 2012 September-October. The flare was tracked from gamma-ray to near-infrared frequencies…

astro-ph.GA2016★ 46 cited

Long-term multi-wavelength variability and correlation study of Markarian 421 from 2007 to 2009

MAGIC Collaboration, M. L. Ahnen, S. Ansoldi +176

We study the multi-band variability and correlations of the TeV blazar Mrk 421 on year time scales, which can bring additional insight on the processes responsible for its broadban…

astro-ph.HE2015★ 143 cited

Multiwavelength Study of Quiescent States of Mrk 421 with Unprecedented Hard X-Ray Coverage Provided by NuSTAR in 2013

M. Baloković, D. Paneque, G. Madejski +305

We present coordinated multiwavelength observations of the bright, nearby BL Lac object Mrk 421 taken in 2013 January-March, involving GASP-WEBT, Swift, NuSTAR, Fermi-LAT, MAGIC, V…

astro-ph.HE2015★ 45 cited

The WEBT campaign on the BL Lac object PG 1553+113 in 2013. An analysis of the enigmatic synchrotron emission

C. M. Raiteri, A. Stamerra, M. Villata +2

A multifrequency campaign on the BL Lac object PG 1553+113 was organized by the Whole Earth Blazar Telescope (WEBT) in 2013 April-August, involving 19 optical, two near-IR, and thr…

astro-ph.HE2014★ 28 cited

The connection between the parsec-scale radio jet and gamma-ray flares in the blazar 1156+295

Venkatessh Ramakrishnan, Jonathan León-Tavares, Elizaveta A. Rastorgueva-Foi +30

The blazar 1156+295 was active at gamma-ray energies, exhibiting three prominent flares during the year 2010. Here, we present results using the combination of broadband (X-ray thr…

astro-ph.HE2014★ 49 cited

Comprehensive Monitoring of Gamma-ray Bright Blazars. I. Statistical Study of Optical, X-ray, and Gamma-ray Spectral Slopes

Karen E. Williamson, Svetlana G. Jorstad, Alan P. Marscher +21

We present -ray, X-ray, ultraviolet, optical, and near-infrared light curves of 33 -ray bright blazars over four years that we have been monitoring since 2008 August with mul…

astro-ph.HE2014★ 97 cited

MAGIC gamma-ray and multifrequency observations of flat spectrum radio quasar PKS 1510-089 in early 2012

MAGIC Collaboration, J. Aleksić, S. Ansoldi +218

Among more than fifty blazars detected in very high energy (VHE, E>100GeV) gamma-rays, only three belong to the subclass of Flat Spectrum Radio Quasars (FSRQs). MAGIC observed FSRQ…

astro-ph.HE2013★ 14 cited

Analyzing polarization swings in 3C 279

S. Kiehlmann, T. Savolainen, S. G. Jorstad +53

Quasar 3C 279 is known to exhibit episodes of optical polarization angle rotation. We present new, well-sampled optical polarization data for 3C 279 and introduce a method to disti…

astro-ph.HE2013★ 189 cited

A Tight Connection between Gamma-Ray Outbursts and Parsec-Scale Jet Activity in the Quasar 3C 454.3

Svetlana G. Jorstad, Alan P. Marscher, Paul S. Smith +42

We analyze the multifrequency behavior of the quasar 3C 454.3 during three prominent γ-ray outbursts: 2009 Autumn, 2010 Spring, and 2010 Autumn. The data reveal a repeating pattern…

astro-ph.HE2012★ 64 cited

Variability of the blazar 4C 38.41 (B3 1633+382) from GHz frequencies to GeV energies

C. M. Raiteri, M. Villata, P. S. Smith +74

The quasar-type blazar 4C 38.41 (B3 1633+382) experienced a large outburst in 2011, which was detected throughout the entire electromagnetic spectrum. We present the results of low…

astro-ph.HE2012★ 65 cited

Multi-wavelength observations of blazar AO 0235+164 in the 2008-2009 flaring state

M. Ackermann, M. Ajello, J. Ballet +208

The blazar AO 0235+164 (z = 0.94) has been one of the most active objects observed by Fermi Large Area Telescope (LAT) since its launch in Summer 2008. In addition to the continuou…

astro-ph.CO2011★ 10 cited

Identification of gamma-ray emission from 3C345 and NRAO512

F. K. Schinzel, K. V. Sokolovsky, F. D'Ammando +36

For more than 15 years, since the days of the Energetic Gamma-Ray Experiment Telescope (EGRET) on board the Compton Gamma-Ray Observatory (CGRO; 1991-2000), it has remained an open…