Related papers: Long-term study of Mkn 421 with the HAGAR Array of…

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

Study of the variable broadband emission of Markarian 501 during the most extreme Swift X-ray activity

Mrk501 is a very high-energy (VHE) gamma-ray blazar located at z=0.034. During a period of two weeks in July 2014, the highest X-ray activity of Mrk501 was observed in ~14 years of operation of the Neil Gehrels Swift Gamma-ray Burst…

High Energy Astrophysical Phenomena · Physics 2021-03-17 MAGIC Collaboration , V. A. Acciari , S. Ansoldi , L. A. Antonelli , A. Babić , B. Banerjee , U. Barres de Almeida , J. A. Barrio , J. Becerra González , W. Bednarek , E. Bernardini , A. Berti , J. Besenrieder , W. Bhattacharyya , C. Bigongiari , O. Blanch , G. Bonnoli , G. Busetto , R. Carosi , G. Ceribella , S. Cikota , S. M. Colak , P. 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 , A. Domínguez , D. Dominis Prester , M. Doro , 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 , P. Giammaria , N. Godinović , D. Guberman , D. Hadasch , A. Hahn , T. Hassan , J. Herrera , J. Hoang , D. Hrupec , S. Inoue , K. Ishio , Y. Iwamura , H. Kubo , J. Kushida , D. Kuveždić , A. Lamastra , D. Lelas , F. Leone , E. Lindfors , S. Lombardi , F. Longo , M. López , A. López-Oramas , B. Machado de Oliveira Fraga , C. Maggio , P. Majumdar , M. Makariev , M. Mallamaci , G. Maneva , M. Manganaro , L. Maraschi , M. Mariotti , M. Martínez , S. Masuda , D. Mazin , M. Minev , J. M. Miranda , R. Mirzoyan , E. Molina , A. Moralejo , V. Moreno , E. Moretti , P. Munar-Adrove r , V. Neustroev , A. Niedzwiecki , M. Nievas Rosillo , C. Nigro , K. Nilsson , D. Ninci , K. Nishijima , K. Noda , L. Nogués , S. Paiano , J. Palacio , D. Paneque , R. Paoletti , J. M. Paredes , G. Pedaletti , P. Peñil , M. Peresano , M. Persic , P. G. Prada Moroni , E. Prandini , I. Puljak , J. R. Garcia , 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 , M. Strzys , T. Surić , F. Tavecchio , P. Temnikov , T. Terzić , M. Teshima , N. Torres-Albá , S. Tsujimoto , J. van Scherpenberg , G. Vanzo , M. Vazquez Acosta , I. Vovk , M. Will , D. Zarić , FACT Collaboration , : , A. Arbet-Engels , D. Baack , M. Balbo , A. Biland , M. Blank , T. Bretz , K. Bruegge , M. Bulinski , J. Buss , M. Doerr , D. Dorner , S. Einecke , D. Elsaesser , D. Hildebrand , L. Linhoff , K. Mannheim , S. Mueller , D. Neise , A. Neronov , M. Noethe , A. Paravac , W. Rhode , B. Schleicher , F. Schulz , K. Sedlaczek , A. Shukla , V. Sliusar , E. von Willert , R. Walter , C. Wendel , A. Tramacere , A. Lien , M. Perri , F. Verrecchia , M. Armas Padilla , C. Leto , A. Lähteenmäki , M. Tornikoski , J. Tammi

Unveiling the X-ray/TeV engine in Mkn 421

Simultaneous observations of Mkn 421 were taken in very high energy gamma -rays (>200 GeV, CAT experiment), X-rays (RXTE) and optical (KVA). Multi -day RXTE observations are also presented, allowing for detailed modelling of the spectral…

Astrophysics · Physics 2008-11-26 Berrie Giebels , Guillaume Dubus , Bruno Khelifi

Multi-wavelength study of blazar 4C +01.02 during its long-term flaring activity in 2014-2017

We conducted a detailed long-term spectral and temporal study of flat spectrum radio quasar 4C +01.02, by using the multi-wavelength observations from Fermi-LAT, Swift-XRT, and Swift-UVOT. The $2$-day bin $\gamma$-ray lightcurve in the…

High Energy Astrophysical Phenomena · Physics 2022-06-22 Malik Zahoor , Shah Zahir , Sunder Sahayanathan , Naseer Iqbal , Aaqib Manzoor

X-ray Intra-day Variability of the TeV Blazar Mrk 421 with Suzaku

We present X-ray flux and spectral analyses of the three pointed Suzaku observations of the TeV high synchrotron peak blazar Mrk 421 taken throughout its complete operational duration. The observation taken on 5 May 2008 is, at 364.6…

High Energy Astrophysical Phenomena · Physics 2019-11-06 Zhongli Zhang , Alok C. Gupta , Haritma Gaur , Paul J. Wiita , Tao An , Minfeng Gu , Dan Hu , Haiguang Xu

Reconcilement of VHE $\gamma$-ray/X-ray correlation studies in Mrk 421 and break-down at high fluxes

Multi-wavelength campaigns have been carried out to study the correlation between the very high energy (VHE) $\gamma$-ray and the X-ray emissions in blazars but, no conclusive results have been achieved yet. In this paper, we add Milagro…

High Energy Astrophysical Phenomena · Physics 2019-01-30 M. M. González , B. Patricelli , N. Fraija , J. A. García-González

20 years of monitoring: PKS 2155-304 and PKS 1510-089 in the eyes of Swift and Fermi. I. The case of PKS 2155-304

We present a comprehensive 20-year multiwavelength variability study of the blazar PKS 2155-304, one of the most luminous and extensively monitored high-frequency-peaked BL Lac objects in the southern hemisphere. Using Fermi-LAT…

High Energy Astrophysical Phenomena · Physics 2026-04-02 A. Wierzcholska , M. Zacharias

Blazar Variability: A Study of Non-stationarity and the Flux-RMS Relation

We analyze X-ray light curves of the blazars Mrk 421, PKS 2155-304, and 3C 273 using observations by the Soft X-ray Telescope on board AstroSat and archival XMM-Newton data. We use light curves of length 30-90 ks each from 3-4 epochs for…

High Energy Astrophysical Phenomena · Physics 2023-10-27 Joy Bhattacharyya , Ritesh Ghosh , Ritaban Chatterjee , Nabanita Das

Flux Distribution of Gamma-Ray Emission in Blazars: The Example of Mrk 501

Flux distribution is an important tool to understand the variability processes in active galactic nuclei. We now have available a great deal of observational evidences pointing towards the presence of log-normal components in the high…

High Energy Astrophysical Phenomena · Physics 2018-12-18 Carlo Romoli , Nachiketa Chakraborty , Daniela Dorner , Andrew M. Taylor , Michael Blank

Temporal analysis of an unprecedented data set for the $\gamma$-ray blazar 1ES 1215+303: Fermi-LAT and VERITAS light curves spanning ten years

We present here the results of the analysis of the $\gamma$-ray blazar, 1ES 1215+303, over a 10-year period, from 2008 to 2017, measured at high energies (HE; 200 MeV $< E <$ 100 GeV) by the Fermi Large Area Telescope (LAT) and at very high…

High Energy Astrophysical Phenomena · Physics 2017-12-19 Janeth Valverde , Deirdre Horan , Giuliana Noto , Reshmi Mukherjee , Denis Bernard

Unveiling the broadband spectral and temporal properties of PKS\,0903-57 during its brightest flare

We carried a detailed spectral and temporal study of blazar, \mbox{PKS\,0903-57} using the \emph{Fermi}-LAT and \emph{Swift}-XRT/UVOT observations, during its brightest flaring period MJD\,58931--58970. During this period, the maximum daily…

High Energy Astrophysical Phenomena · Physics 2021-06-03 Zahir Shah , V. Jithesh , S. Sahayanathan , Naseer Iqbal

A Comprehensive Statistical Description of Radio-Through-$\gamma$-Ray Spectral Energy Distributions of All Known Blazars

We combined multi-wavelength data for blazars from the Roma-BZCAT catalog and analyzed hundreds of X-ray spectra. We present the fluxes and Spectral Energy Distributions (SEDs), in 12 frequency bands from radio to $\gamma$-rays, for a final…

Astrophysics of Galaxies · Physics 2016-06-17 Peiyuan Mao , C. Megan Urry , Francesco Massaro , Alessandro Paggi , Joe Cauteruccio , Soren R. Künzel

Joint analysis of TeV blazar light curves with FACT and HAWC

Probing the high energy emission processes of blazars through their variability relies crucially on long-term monitoring. We present unprecedented light curves from unbiased observations of very high energy fluxes from the blazars Mrk 421…

High Energy Astrophysical Phenomena · Physics 2019-08-15 Daniela Dorner , Robert J. Lauer

Multiwavelength Observations of the Blazar Mrk 421 in December 2002 and January 2003

We report on a multiwavelength campaign on the TeV gamma-ray blazar Markarian (Mrk) 421 performed during December 2002 and January 2003. These target of opportunity observations were initiated by the detection of X-ray and TeV gamma-ray…

Astrophysics · Physics 2019-08-15 P. Rebillot , M. Aller , H. Aller , P. Boltwood , I. Jung , D. Kranich , A. Sillanpaa , A. Sadun

Time-Dependent Modeling of the Sub-Hour Spectral Evolution During the 2013 Outburst of Mrk 421

In April 2013, the TeV blazar Markarian~421 underwent one of its most powerful emission outbursts to date. An extensive multi-instrument campaign featuring MAGIC, VERITAS, and \textit{NuSTAR} provided comprehensive very-high-energy (VHE; $E…

High Energy Astrophysical Phenomena · Physics 2026-03-06 MAGIC Collaboration , K. Abe , S. Abe , J. Abhir , A. Abhishek , A. Aguasca-Cabot , I. Agudo , T. Aniello , S. Ansoldi , L. A. Antonelli , A. Arbet Engels , C. Arcaro , T. T. H. Arnesen , A. Babić , C. Bakshi , U. Barres de Almeida , J. A. Barrio , L. Barrios-Jiménez , I. Batković , J. Baxter , J. Becerra González , W. Bednarek , E. Bernardini , J. Bernete , A. Berti , C. Bigongiari , A. Biland , O. Blanch , G. Bonnoli , Ž Bošnjak , E. Bronzini , I. Burelli , A. Campoy-Ordaz , A. Carosi , R. Carosi , M. Carretero-Castrillo , A. J. Castro-Tirado , D. Cerasole , G. Ceribella , Y. Chai , A. Cifuentes , J. L. Contreras , J. Cortina , S. Covino , F. D'Ammando , P. Da Vela , F. Dazzi , A. De Angelis , B. De Lotto , R. de Menezes , J. Delgado , C. Delgado Mendez , F. Di Pierro , R. Di Tria , L. Di Venere , A. Dinesh , D. Dominis Prester , A. Donini , D. Dorner , M. Doro , L. Eisenberger , D. Elsaesser , J. Escudero , L. Fariña , L. Foffano , L. Font , S. Fröse , Y. Fukazawa , R. J. García López , S. García Soto , M. Garczarczyk , S. Gasparyan , J. G. Giesbrecht Paiva , N. Giglietto , F. Giordano , P. Gliwny , T. Gradetzke , R. Grau , D. Green , J. G. Green , P. Günther , A. Hahn , T. Hassan , L. Heckmann , J. Herrera Llorente , D. Hrupec , D. Israyelyan , J. Jahanvi , I. Jiménez Martínez , J. Jiménez Quiles , J. Jormanainen , S. Kankkunen , T. Kayanoki , J. Konrad , P. M. Kouch , G. Koziol , H. Kubo , J. Kushida , M. Laínez , A. Lamastra , E. Lindfors , S. Lombardi , F. Longo , M. López-Moya , A. López-Oramas , S. Loporchio , L. Lulić , E. Lyard , P. Majumdar , M. Makariev , M. Mallamaci , G. Maneva , M. Manganaro , S. Mangano , K. Mannheim , S. Marchesi , M. Mariotti , M. Martínez , P. Maruševec , S. Menchiari , J. Méndez Gallego , S. Menon , D. Miceli , J. M. Miranda , R. Mirzoyan , M. Molero González , E. Molina , H. A. Mondal , A. Moralejo , C. Nanci , A. Negro , V. Neustroev , L. Nickel , M. Nievas Rosillo , C. Nigro , L. Nikolić , S. Nozaki , A. Okumura , J. Otero-Santos , S. Paiano , D. Paneque , R. Paoletti , J. M. Paredes , M. Peresano , M. Persic , M. Pihet , G. Pirola , F. Podobnik , P. G. Prada Moroni , E. Prandini , W. Rhode , M. Ribó , J. Rico , A. Roy , N. Sahakyan , F. G. Saturni , K. Schmitz , F. Schmuckermaier , T. Schweizer , A. Sciaccaluga , G. Silvestri , A. Simongini , J. Sitarek , V. Sliusar , D. Sobczynska , A. Stamerra , J. Strišković , D. Strom , M. Strzys , Y. Suda , H. Tajima , R. Takeishi , F. Tavecchio , T. Terzić , M. Teshima , A. Tutone , S. Ubach , J. van Scherpenberg , M. Vazquez Acosta , S. Ventura , G. Verna , I. Viale , A. Vigliano , C. F. Vigorito , E. Visentin , V. Vitale , I. Vovk , R. Walter , F. Wersig , M. Will , T. Yamamoto , P. K. H. Yeung , M. Petropoulou , M. Polkas , A. Mastichiadis

Time dependent simulations of multiwavelength variability of the blazar Mrk 421 with a Monte Carlo multi-zone code

(abridged) We present a new time-dependent multi-zone radiative transfer code and its application to study the SSC emission of Mrk 421. The code couples Fokker-Planck and Monte Carlo methods, in a 2D geometry. For the first time all the…

High Energy Astrophysical Phenomena · Physics 2011-09-22 Xuhui Chen , Giovanni Fossati , Edison Liang , Markus Boettcher

Multiwavelength study of TeV Blazar Mrk421 during giant flare

Context: The nearby (z=0.031) TeV blazar Mrk421 was reported to be in a high state of flux activity since November, 2009. Aims: To investigate possible changes in the physical parameters of Mrk421 during its high state of activity using…

High Energy Astrophysical Phenomena · Physics 2015-06-04 A. Shukla , V. R. Chitnis , P. R. Vishwanath , B. S. Acharya , G. C. Anupama , P. Bhattacharjee , R. J. Britto , T. P. Prabhu , L. Saha , B. B. Singh

The TANAMI Multiwavelength Program: Dynamic SEDs of Southern Blazars

Simultaneous broadband spectral and temporal studies of blazars are an important tool for investigating active galactic nuclei (AGN) jet physics. We study the spectral evolution between quiescent and flaring periods of 22 radio-loud AGN…

High Energy Astrophysical Phenomena · Physics 2016-06-29 Felicia Krauß , Joern Wilms , Matthias Kadler , Roopesh Ojha , Robert Schulz , Jonas Trüstedt , Philip G. Edwards , Jamie Stevens , Eduardo Ros , Wayne Baumgartner , Tobias Beuchert , Jay Blanchard , Sara Buson , Bryce Carpenter , Thomas Dauser , Sebastian Falkner , Neil Gehrels , Christina Gräfe , Sergei Gulyaev , Hayo Hase , Shinji Horiuchi , Annika Kreikenbohm , Ingo Kreykenbohm , Marcus Langejahn , Katharina Leiter , Jim E. J. Lovell , Cornelia Müller , Tim Natusch , Roberto Nesci , Tapio Pursimo , Chris Phillips , Christian Plötz , Jonathan Quick , Anastasios K. Tzioumis , Stuart Weston

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

Cross-spectral analysis of the X-ray variability of Mrk 421

Using the cross-spectral method, we confirm the existence of the X-ray hard lags discovered with cross-correlation function technique during a large flare of Mrk 421 observed with BeppoSAX . For the 0.1--2 versus 2--10keV light curves, both…

Astrophysics · Physics 2009-11-07 Y. H. Zhang