Related papers: Rapid X-ray Variability in Mkn 421 during a Multiw…

Broadband Spectro-temporal Study on Blazar TXS 1700+685

We attempt to present a multiwavelength variability and correlation study as well as detailed multi-waveband spectral characteristics of the May 2021 $\gamma$-ray flare of the blazar source TXS 1700+685. The multi-wavelength observation…

High Energy Astrophysical Phenomena · Physics 2022-08-03 Anuvab Banerjee , Prantik Nandi , Raj Prince , Rukaiya Khatoon , Debanjan Bose

A time dependent approach to model X-ray and $\gamma$--ray light curves of Mrk 421 observed during the flare in February 2010

Strong X-ray and $\gamma$--ray flares have been detected in February 2010 from the high synchrotron peaked blazar Mrk 421 (z=0.031). With the motivation of understanding the physics involved in this flaring activity, we study the…

High Energy Astrophysical Phenomena · Physics 2017-01-11 K K Singh , S Sahayanathan , A Sinha , N Bhatt , A K Tickoo , K K Yadav , R C Rannot , P Chandra , K Venugopal , P Marandi , N Kumar , H C Goyal , A Goyal , N K Agarwal , M Kothari , K Chanchalani , V K Dhar , N Chouhan , C K Bhat , M K Koul , R Koul

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

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 includes, among other instruments, MAGIC, VERITAS, Whipple…

High Energy Astrophysical Phenomena · Physics 2017-07-05 M. L. Ahnen , S. Ansoldi , L. A. Antonelli , P. Antoranz , A. Babic , B. Banerjee , P. Bangale , U. Barres de Almeida , J. A. Barrio , J. Becerra González , W. Bednarek , E. Bernardini , A. Berti , B. Biasuzzi , A. Biland , O. Blanch , S. Bonnefoy , G. Bonnoli , F. Borracci , T. Bretz , S. Buson , A. Carosi , A. Chatterjee , R. Clavero , P. Colin , E. Colombo , J. L. Contreras , J. Cortina , S. Covino , P. Da Vela , F. Dazzi , A. De Angelis , B. De Lotto , E. de Ona Wilhelmi , F. Di Pierro , M. Doert , A. Domínguez , D. Dominis Prester , D. Dorner , M. Doro , S. Einecke , D. Eisenacher Glawion , D. Elsaesser , M. Engelkemeier , V. Fallah Ramazani , A. Fernández-Barral , D. Fidalgo , M. V. Fonseca , L. Font , K. Frantzen , C. Fruck , D. Galindo , R. J. García López , M. Garczarczyk , D. Garrido Terrats , M. Gaug , P. Giammaria , N. Godinović , A. González Munoz , D. Gora , D. Guberman , D. Hadasch , A. Hahn , Y. Hanabata , M. Hayashida , J. Herrera , J. Hose , D. Hrupec , G. Hughes , W. Idec , K. Kodani , Y. Konno , H. Kubo , J. Kushida , A. La Barbera , D. Lelas , E. Lindfors , S. Lombardi , F. Longo , M. López , R. López-Coto , P. Majumdar , M. Makariev , K. Mallot , G. Maneva , M. Manganaro , K. Mannheim , L. Maraschi , B. Marcote , M. Mariotti , M. Martínez , D. Mazin , U. Menzel , J. M. Miranda , R. Mirzoyan , A. Moralejo , E. Moretti , D. Nakajima , V. Neustroev , A. Niedzwiecki , M. Nievas Rosillo , K. Nilsson , K. Nishijima , K. Noda , L. Nogués , A. Overkemping , S. Paiano , J. Palacio , M. Palatiello , D. Paneque , R. Paoletti , J. M. Paredes , X. Paredes-Fortuny , G. Pedaletti , M. Peresano , L. Perri , M. Persic , J. Poutanen , P. G. Prada Moroni , E. Prandini , I. Puljak , I. Reichardt , W. Rhode , M. Ribó , J. Rico , J. Rodriguez Garcia , T. Saito , K. Satalecka , S. Schröder , C. Schultz , T. Schweizer , S. N. Shore , A. Sillanpää , J. Sitarek , I. Snidaric , D. Sobczynska , A. Stamerra , T. Steinbring , M. Strzys , T. Surić , L. Takalo , F. Tavecchio , P. Temnikov , T. Terzić , D. Tescaro , M. Teshima , J. Thaele , D. F. Torres , T. Toyama , A. Treves , G. Vanzo , V. Verguilov , I. Vovk , J. E. Ward , M. Will , M. H. Wu , R. Zanin , A. U. Abeysekara , S. Archambault , A. Archer , W. Benbow , R. Bird , M. Buchovecky , J. H. Buckley , V. Bugaev , M. P. Connolly , W. Cui , H. J. Dickinson , A. Falcone , Q. Feng , J. P. Finley , H. Fleischhack , A. Flinders , L. Fortson , G. H. Gillanders , S. Griffin , J. Grube , M. Hütten , D. Hanna , J. Holder , T. B. Humensky , P. Kaaret , P. Kar , N. Kelley-Hoskins , M. Kertzman , D. Kieda , M. Krause , F. Krennrich , M. J. Lang , G. Maier , A. McCann , P. Moriarty , R. Mukherjee , D. Nieto , S. O'Brien , R. A. Ong , N. Otte , N. Park , J. Perkins , A. Pichel , M. Pohl , A. Popkow , E. Pueschel , J. Quinn , K. Ragan , P. T. Reynolds , G. T. Richards , E. Roache , A. C. Rovero , C. Rulten , I. Sadeh , M. Santander , G. H. Sembroski , K. Shahinyan , I. Telezhinsky , J. V. Tucci , J. Tyler , S. P. Wakely , A. Weinstein , P. Wilcox , A. Wilhelm , D. A. Williams , B. Zitzer , S. Razzaque , M. Villata , C. M. Raiteri , H. D. Aller , M. F. Aller , V. M. Larionov , A. A. Arkharov , D. A. Blinov , N. V. Efimova , T. S. Grishina , V. A. Hagen-Thorn , E. N. Kopatskaya , L. V. Larionova , E. G. Larionova , D. A. Morozova , I. S. Troitsky , R. Ligustri , P. Calcidese , A. Berdyugin , O. M. Kurtanidze , M. G. Nikolashvili , G. N. Kimeridze , L. A. Sigua , S. O. Kurtanidze , R. A. Chigladze , W. P. Chen , E. Koptelova , T. Sakamoto , A. C. Sadun , J. W. Moody , C. Pace , R. Pearson , Y. Yatsu , Y. Mori , A. Carraminyana , L. Carrasco , E. de la Fuente , J. P. Norris , P. S. Smith , A. Wehrle , M. A. Gurwell , Alma Zook , C. Pagani , M. Perri , M. Capalbi , A. Cesarini , H. A. Krimm , Y. Y. Kovalev , Yu. A. Kovalev , E. Ros , A. B. Pushkarev , M. L. Lister , K. V. Sokolovsky , M. Kadler , G. Piner , A. Lähteenmäki , M. Tornikoski , E. Angelakis , T. P. Krichbaum , I. Nestoras , L Fuhrmann , J. A. Zensus , P. Cassaro , A. Orlati , G. Maccaferri , P. Leto , M. Giroletti , J. L. Richards , W. Max-Moerbeck , A. C. S. Readhead

Multifrequency Photo-polarimetric WEBT Observation Campaign on the Blazar S5 0716+714: Source Microvariability and Search for Characteristic Timescales

Here we report on the results of the WEBT photo-polarimetric campaign targeting the blazar S5~0716+71, organized in March 2014 to monitor the source simultaneously in BVRI and near IR filters. The campaign resulted in an unprecedented…

High Energy Astrophysical Phenomena · Physics 2016-11-09 G. Bhatta , Ł. Stawarz , M. Ostrowski , A. Markowitz , H. Akitaya , A. A. Arkharov , R. Bachev , E. Benítez , G. A. Borman , D. Carosati , A. D. Cason , R. Chanishvili , G. Damljanovic , S. Dhalla , A. Frasca , D. Hiriart , S-M. Hu , R. Itoh , D. Jableka , S. Jorstad , M. D. Jovanovic , K. S. Kawabata , S. A. Klimanov , O. Kurtanidze , V. M. Larionov , D. Laurence , G. Leto , A. P. Marscher , J. W. Moody , Y. Moritani , J. M. Ohlert , A. Di Paola , C. M. Raiteri , N. Rizzi , A. C. Sadun , M. Sasada , S. Sergeev , A. Strigachev , K. Takaki , I. S. Troitsky , T. Ui , M. Villata , O. Vince , J. R. Webb , M. Yoshida , S. Zola

Particle diffusion and localized acceleration in inhomogeneous AGN jets - Part II: stochastic variation

We study the stochastic variation of blazar emission under a 2-D spatially resolved leptonic jet model we previously developed. Random events of particle acceleration and injection in small zones within the emission region are assumed to be…

High Energy Astrophysical Phenomena · Physics 2016-03-23 Xuhui Chen , Martin Pohl , Markus Böttcher , Shan Gao

High-energy variability of the gravitationally lensed blazar PKS 1830-211

The production site and process responsible for the highly variable high-energy emission observed from blazar jets are still debated. Gravitational lenses can be used as microscopes to investigate the nature of such sources. We study the…

High Energy Astrophysical Phenomena · Physics 2025-10-09 Sarah M. Wagner , Jeffrey D. Scargle , Greg Madejski , Andrea Gokus , Krzysztof Nalewajko , Patrick Günther , Karl Mannheim

Magnetic Field Properties inside the Jet of Mrk 421: Multiwavelength Polarimetry Including the Imaging X-ray Polarimetry Explorer

We conducted a polarimetry campaign from radio to X-ray wavelengths of the high-synchrotron-peak (HSP) blazar Mrk 421, including Imaging X-ray Polarimetry Explorer (IXPE) measurements on 2022 December 6-8. We detected X-ray polarization of…

High Energy Astrophysical Phenomena · Physics 2024-01-10 Dawoon E. Kim , Laura Di Gesu , Ioannis Liodakis , Alan P. Marscher , Svetlana G. Jorstad , Riccardo Midde , Herman L. Marshall , Luigi Pacciani , Iván Agudo , Fabrizio Tavecchio , Nicolò Cibrario , Stefano Tugliani , Raffaella Bonino , Michela Negro , Simonetta Puccetti , Francesco Tombesi , Enrico Costa , Immacolata Donnarumma , Paolo Soffitta , Tsunefumi Mizuno , Yasushi Fukazawa , Koji S. Kawabata , Tatsuya Nakaoka , Makoto Uemura , Ryo Imazawa , Mahito Sasada , Hiroshi Akitaya , Francisco Josè Aceituno , Giacomo Bonnoli , Vìctor Casanova , Ioannis Myserlis , Albrecht Sievers , Emmanouil Angelakis , Alexander Kraus , Whee Yeon Cheong , Hyeon-Woo Jeong , Sincheol Kang , Sang-Hyun Kim , Sang-Sung Lee , Beatriz Agìs-Gonzàlez , Alfredo Sota , Juan Escudero , Mark Gurwell , Garrett K. Keating , Ramprasad Rao , Pouya M. Kouch , Elina Lindfors , Ioakeim G. Bourbah , Sebastian Kiehlmann , Evangelos Kontopodis , Nikos Mandarakas , Stylianos Romanopoulos , Raphael Skalidis , Anna Vervelaki , Sergey S. Savchenko , Lucio A. Antonelli , Matteo Bachetti , Luca Baldini , Wayne H. Baumgartner , Ronaldo Bellazzini , Stefano Bianchi , Stephen D. Bongiorno , Alessandro Brez , Niccolò Bucciantini , Fiamma Capitanio , Simone Castellano , Elisabetta Cavazzuti , Chien-Ting Chen , Stefano Ciprini , Alessandra De Rosa , Ettore Del Monte , Niccolò Di Lalla , Alessandro Di Marco , Victor Doroshenko , Michal Dovčiak , Steven R. Ehlert , Teruaki Enoto , Yuri Evangelista , Sergio Fabiani , Riccardo Ferrazzoli , Javier A. Garcia , Shuichi Gunji , Kiyoshi Hayashida , Jeremy Heyl , Wataru Iwakiri , Philip Kaaret , Vladimir Karas , Fabian Kislat , Takao Kitaguchi , Jeffery J. Kolodziejczak , Henric Krawczynski , Fabio La Monaca , Luca Latronico , Simone Maldera , Alberto Manfreda , Frédéric Marin , Andrea Marinucci , Francesco Massaro , Giorgio Matt , Ikuyuki Mitsuishi , Fabio Muleri , C. -Y. Ng , Stephen L. O'Dell , Nicola Omodei , Chiara Oppedisano , Alessandro Papitto , George G. Pavlov , Abel L. Peirson , Matteo Perri , Melissa Pesce-Rollins , Pierre-Olivier Petrucci , Maura Pilia , Andrea Possenti , Juri Poutanen , Brian D. Ramsey , John Rankin , Ajay Ratheesh , Oliver Roberts , Roger W. Romani , Carmelo Sgrò , Patrick Slane , Gloria Spandre , Doug Swartz , Toru Tamagawa , Roberto Taverna , Yuzuru Tawara , Allyn F. Tennant , Nicholas E. Thomas , Alessio Trois , Sergey S. Tsygankov , Roberto Turolla , Jacco Vink , Martin C. Weisskopf , Kinwah Wu , Fei Xie , Silvia Zane

Simultaneous Multiwavelength observation of Mkn 501 in a low state in 2006

We present results of the multiwavelength campaign on the TeV blazar Mkn 501 performed in 2006 July, including MAGIC for the VHE gamma-ray band and Suzaku for the X-ray band. A VHE gamma-ray signal was clearly detected with an average flux…

High Energy Astrophysical Phenomena · Physics 2009-12-04 The MAGIC Collaboration , H. Anderhub , R. Sato , M. Ushio , J. Kataoka , G. Madejski , T. Takahashi

Coordinated Multiwavelength Observations and Spectral Variability Modeling of Gamma-Ray Blazars

Our recent progress on time-dependent modeling of the multiwavelength spectra and variability of blazars with leptonic and hadronic jet models is reviewed. Special emphasis is placed on X-ray spectral variability of low-frequency peaked…

Astrophysics · Physics 2007-05-23 M. Boettcher

The Great Markarian 421 Flare of February 2010: Multiwavelength variability and correlation studies

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 level of $\sim$27~Crab Units above 1~TeV was measured in…

High Energy Astrophysical Phenomena · Physics 2020-04-06 A. U. Abeysekara , W. Benbow , R. Bird , A. Brill , R. Brose , M. Buchovecky , J. H. Buckley , J. L. Christiansen , A. J. Chromey , M. K. Daniel , J. Dumm , A. Falcone , Q. Feng , J. P. Finley , L. Fortson , A. Furniss , N. Galante , A. Gent , G. H. Gillanders , C. Giuri , O. Gueta , T. Hassan , O. Hervet , J. Holder , G. Hughes , T. B. Humensky , C. A. Johnson , P. Kaaret , P. Kar , N. Kelley-Hoskins , M. Kertzman , D. Kieda , M. Krause , F. Krennrich , S. Kumar , M. J. Lang , P. Moriarty , R. Mukherjee , T. Nelson , D. Nieto , M. Nievas-Rosillo , S. O'Brien , R. A. Ong , A. N. Otte , N. Park , A. Petrashyk , A. Pichel , M. Pohl , R. R. Prado , E. Pueschel , J. Quinn , K. Ragan , P. T. Reynolds , G. T. Richards , E. Roache , A. C. Rovero , C. Rulten , I. Sadeh , M. Santander , G. H. Sembroski , K. Shahinyan , B. Stevenson , I. Sushch , J. Tyler , V. V. Vassiliev , S. P. Wakely , A. Weinstein , R. M. Wells , P. Wilcox , A. Wilhelm , D. A. Williams , B. Zitzer , V. A. Acciari , S. Ansoldi , L. A. Antonelli , A. Arbet Engels , D. Baack , A. Babić , B. Banerjee , U. Barres de Almeida , J. A. Barrio , J. Becerra González , W. Bednarek , L. Bellizzi , E. Bernardini , A. Berti , J. Besenrieder , W. Bhattacharyya , C. Bigongiari , A. Biland , O. Blanch , G. Bonnoli , G. Busetto , R. Carosi , G. Ceribella , Y. Chai , S. Cikota , S. M. Colak , U. Colin , E. Colombo , J. L. Contreras , J. Cortina , S. Covino , V. D'Elia , P. Da Vela , F. Dazzi , A. De Angelis , B. De Lotto , M. Delfino , J. Delgado , F. Di Pierro , E. Do Souto Espiñera , D. Dominis Prester , D. Dorner , M. Doro , S. Einecke , D. Elsaesser , V. Fallah Ramazani , A. Fattorini , A. Fernández-Barral , G. Ferrara , D. Fidalgo , L. Foffano , M. V. Fonseca , L. Font , C. Fruck , D. Galindo , S. Gallozzi , R. J. García López , M. Garczarczyk , S. Gasparyan , M. Gaug , N. Godinović , D. Green , D. Guberman , D. Hadasch , A. Hahn , J. Herrera , J. Hoang , D. Hrupec , S. Inoue , K. Ishio , Y. Iwamura , H. Kubo , J. Kushida , A. Lamastra , D. Lelas , F. Leone , E. Lindfors , S. Lombardi , F. Longo , M. López , R. López-Coto , A. López-Oramas , B. Machado de Oliveira Fraga , C. Maggio , P. Majumdar , M. Makariev , M. Mallamaci , G. Maneva , M. Manganaro , K. Mannheim , L. Maraschi , M. Mariotti , M. Martínez , S. Masuda , D. Mazin , D. Miceli , M. Minev , J. M. Miranda , R. Mirzoyan , E. Molina , A. Moralejo , D. Morcuende , V. Moreno , E. Moretti , P. Munar-Adrover , V. Neustroev , A. Niedzwiecki , M. Nievas Rosillo , C. Nigro , K. Nilsson , D. Ninci , K. Nishijima , K. Noda , L. Nogués , M. Nöthe , S. Paiano , J. Palacio , M. Palatiello , D. Paneque , R. Paoletti , J. M. Paredes , P. Peñil , M. Peresano , M. Persic , P. G. Prada Moroni , E. Prandini , I. Puljak , W. Rhode , M. Ribó , J. Rico , C. Righi , A. Rugliancich , L. Saha , N. Sahakyan , T. Saito , K. Satalecka , T. Schweizer , J. Sitarek , I. Šnidarić , D. Sobczynska , A. Somero , A. Stamerra , D. Strom , M. Strzys , S. Sun , T. Surić , F. Tavecchio , P. Temnikov , T. Terzić , M. Teshima , N. Torres-Albà , S. Tsujimoto , J. van Scherpenberg , G. Vanzo , M. Vazquez Acosta , I. Vovk , M. Will , D. Zarić , H. D. Aller , M. F. Aller , M. T. Carini , D. Horan , B. Jordan , Svetlana G. Jorstad , O. M. Kurtanidze , S. O. Kurtanidze , A. Lähteenmäki , V. M. Larionov , E. G. Larionova , G. Madejski , Alan P. Marscher , W. Max-Moerbeck , J. Ward Moody , D. A. Morozova , M. G. Nikolashvili , C. M. Raiteri , A. C. S. Readhead , J. L. Richards , Alberto C. Sadun , T. Sakamoto , L. A. Sigua , P. S. Smith , H. Talvikki , J. Tammi , M. Tornikoski , I. S. Troitsky , M. Villata

Not so Swift: 20 years of multiwavelength observations of Mrk 421 and Mrk 501

Aims. The blazars Mrk 421 and Mrk 501 have shown multiwavelength variability on all observed timescales, and have been well studied at high energies on short timescales. We aim to characterise the long-term temporal behaviour of these…

High Energy Astrophysical Phenomena · Physics 2026-02-25 Gabrielle L. Taylor , Stefan J. Wagner , Alicja Wierzcholska , Michael Zacharias

Short time-scale optical variability properties of the largest AGN sample observed with Kepler/K2

We present the first short time-scale ($\sim$hours to days) optical variability study of a large sample of Active Galactic Nuclei (AGN) observed with the Kepler/K2 mission. The sample contains 252 AGN observed over four campaigns with $\sim…

High Energy Astrophysical Phenomena · Physics 2018-03-14 E. Aranzana , E. Kording , P. Uttley , S. Scaringi , S. Bloemen

Blazar variability power spectra from radio up to TeV photon energies: Mrk 421 and PKS 2155-304

We present the results of the power spectral density (PSD) analysis for the blazars Mrk\,421 and PKS\,2155$-$304, using good-quality, densely sampled light curves at multiple frequencies, covering 17 decades of the electromagnetic spectrum,…

High Energy Astrophysical Phenomena · Physics 2020-04-22 Arti Goyal

The WEBT Campaign on the Blazar 3C279 in 2006

The quasar 3C279 was the target of an extensive multiwavelength monitoring campaign from January through April 2006, including an optical-IR-radio monitoring campaign by the Whole Earth Blazar Telescope (WEBT) collaboration. In this paper…

Astrophysics · Physics 2009-11-13 M. Boettcher

The relentless variability of Mrk 421 from the TeV to the radio

The origin of the gamma-ray emission of the blazar Mrk 421 is still a matter of debate. We used 5.5 years of unbiased observing campaign data, obtained using the FACT telescope and the Fermi LAT detector at TeV and GeV energies, the longest…

High Energy Astrophysical Phenomena · Physics 2021-03-17 Axel Arbet-Engels , Dominik Baack , Matteo Balbo , Adrian Biland , Michael Blank , Thomas Bretz , Kai Bruegge , Michael Bulinski , Jens Buss , Manuel Doerr , Daniela Dorner , Dominik Elsaesser , Dorothee Hildebrand , Karl Mannheim , Sebastian Mueller , Dominik Neise , Maximilian Noethe , Aleksander Paravac , Wolfgang Rhode , Bernd Schleicher , Kevin Sedlaczek , Amit Shukla , Vitalii Sliusar , Roland Walter , Elan von Willert

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

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 broadband emission. We observed Mrk 421 in the very high energy…

Astrophysics of Galaxies · Physics 2019-08-15 MAGIC Collaboration , M. L. Ahnen , S. Ansoldi , L. A. Antonelli , P. Antoranz , A. Babic , B. Banerjee , P. Bangale , U. Barres de Almeida , J. A. Barrio , J. Becerra González , W. Bednarek , E. Bernardini , B. Biasuzzi , A. Biland , O. Blanch , S. Bonnefoy , G. Bonnoli , F. Borracci , T. Bretz , S. Buson , A. Carosi , A. Chatterjee , R. Clavero , P. Colin , E. Colombo , J. L. Contreras , J. Cortina , S. Covino , P. Da Vela , F. Dazzi , A. De Angelis , B. De Lotto , E. de Oña Wilhelmi , F. Di Pierro , A. Domínguez , D. Dominis Prester , D. Dorner , M. Doro , S. Einecke , D. Eisenacher Glawion , D. Elsaesser , A. Fernández-Barral , D. Fidalgo , M. V. Fonseca , L. Font , K. Frantzen , C. Fruck , D. Galindo , R. J. García López , M. Garczarczyk , D. Garrido Terrats , M. Gaug , P. Giammaria , N. Godinović , A. González Muñoz , D. Gora , D. Guberman , D. Hadasch , A. Hahn , Y. Hanabata , M. Hayashida , J. Herrera , J. Hose , D. Hrupec , G. Hughes , W. Idec , K. Kodani , Y. Konno , H. Kubo , J. Kushida , A. La Barbera , D. Lelas , E. Lindfors , S. Lombardi , F. Longo , M. López , R. López-Coto , P. Majumdar , M. Makariev , K. Mallot , G. Maneva , M. Manganaro , K. Mannheim , L. Maraschi , B. Marcote , M. Mariotti , M. Martínez , D. Mazin , U. Menzel , J. M. Miranda , R. Mirzoyan , A. Moralejo , E. Moretti , D. Nakajima , V. Neustroev , A. Niedzwiecki , M. Nievas Rosillo , K. Nilsson , K. Nishijima , K. Noda , L. Nogués , R. Orito , A. Overkemping , S. Paiano , J. Palacio , M. Palatiello , D. Paneque , R. Paoletti , J. M. Paredes , X. Paredes-Fortuny , G. Pedaletti , L. Perri , M. Persic , J. Poutanen , P. G. Prada Moroni , E. Prandini , I. Puljak , W. Rhode , M. Ribó , J. Rico , J. Rodriguez Garcia , T. Saito , K. Satalecka , C. Schultz , T. Schweizer , S. N. Shore , A. Sillanpää , J. Sitarek , I. Snidaric , D. Sobczynska , A. Stamerra , T. Steinbring , M. Strzys , L. Takalo , H. Takami , F. Tavecchio , P. Temnikov , T. Terzić , D. Tescaro , M. Teshima , J. Thaele , D. F. Torres , T. Toyama , A. Treves , V. Verguilov , I. Vovk , J. E. Ward , M. Will , M. H. Wu , R. Zanin , D. A. Blinov , W. P. Chen , N. V. Efimova , E. Forné , T. S. Grishina , T. Hovatta , B. Jordan , G. N. Kimeridze , E. N. Kopatskaya , E. Koptelova , O. M. Kurtanidze , S. O. Kurtanidze , A. Lähteenmaäki , V. M. Larionov , E. G. Larionova , L. V. Larionova , R. Ligustri , H. C. Lin , B. McBreen , D. A. Morozova , M. G. Nikolashvili , C. M. Raiteri , J. A. Ros , A. C. Sadun , L. A. Sigua , M. Tornikoski , I. S. Troitsky , M. Villata

A Search for Fast X-ray Variability from Active Galactic Nuclei using Swift

Blazars are a class of active galactic nuclei (AGNs) known for their very rapid variabilty in the high energy regions of the electromagnetic spectrum. Despite this known fast variability, X-ray observations have generally not revealed…

High Energy Astrophysical Phenomena · Physics 2015-06-23 Matthew Pryal , Abe Falcone , Michael Stroh

An Exceptional Radio Flare in Markarian 421

In September 2012, the high-synchrotron-peaked (HSP) blazar Markarian 421 underwent a rapid wideband radio flare, reaching nearly twice the brightest level observed in the centimeter band in over three decades of monitoring. In response to…

High Energy Astrophysical Phenomena · Physics 2015-06-17 Joseph L. Richards , Talvikki Hovatta , Matthew L. Lister , Anthony C. S. Readhead , Walter Max-Moerbeck , Tuomas Savolainen , Emmanouil Angelakis , Lars Fuhrmann , Margo F. Aller , Hugh D. Aller , Ioannis Myserlis , Vassilis Karamanavis

Unusual Flaring Activity in the Blazar PKS 1424-418 during 2008-2011

Context. Blazars are a subset of active galactic nuclei (AGN) with jets that are oriented along our line of sight. Variability and spectral energy distribution (SED) studies are crucial tools for understanding the physical processes…

High Energy Astrophysical Phenomena · Physics 2014-09-17 S. Buson , F. Longo , S. Larsson , S. Cutini , J. Finke , S. Ciprini , R. Ojha , F. D'Ammando , D. Donato , D. J. Thompson , R. Desiante , D Bastieri , S. Wagner , M. Hauser , L. Fuhrmann , M. Dutka , C. Müller , M. Kadler , E. Angelakis , J. A. Zensus , J. Stevens , J. M. Blanchard , P. G. Edwards , J. E. J. Lovell , M. A. Gurwell , A. E. Wehrle , A. Zook

We study simultaneous soft ($0.7 - 7$ keV) and hard ($7 - 20$ keV) X-ray light curves at a total of eight epochs during $2016 - 2019$ of two TeV blazars Mrk 421 and 1ES 1959+650 observed by the SXT and LAXPC instruments onboard AstroSat.…

High Energy Astrophysical Phenomena · Physics 2023-07-27 Susmita Das , Ritaban Chatterjee