English
Related papers

Related papers: Gamma-Ray Flares from Mrk421 in 2008 observed with…

200 papers

VER J0521+211 (RGB J0521.8+2112) is one of the brightest and most powerful blazars detected in the TeV gamma-ray regime. It is located at a redshift of z=0.108 and since its discovery in 2009, VER J0521+211 has exhibited an average TeV flux…

High Energy Astrophysical Phenomena · Physics 2019-08-15 Heike Prokoph , Paolo Da Vela , Cornelia Schultz

We report the detection of a new TeV gamma-ray source, VER J0521+211, based on observations made with the VERITAS imaging atmospheric Cherenkov telescope array. These observations were motivated by the discovery of a cluster of >30GeV…

We report on TeV gamma-ray observations of the blazar Mrk 421 (redshift of 0.031) with the VERITAS observatory and the Whipple 10m Cherenkov telescope. The excellent sensitivity of VERITAS allowed us to sample the TeV gamma-ray fluxes and…

The MAGIC telescope took data of very high energy gamma-ray emission from the blazar Markarian 421 (Mkn 421) between November 2004 and April 2005. We present a combined analysis of data samples recorded under different observational…

Astrophysics · Physics 2008-11-26 J. Albert et al.

The blazar Mrk 421 shows frequent, short flares in the TeV energy regime. Due to the fast nature of such episodes, we often fail to obtain sufficient simultaneous information about flux variations in several energy bands. To overcome this…

The Large Area Telescope on board the Fermi satellite observed a gamma-ray flare in the Crab nebula lasting for approximately nine days in April of 2011. The source, which at optical wavelengths has a size of ~11 ly across, doubled its…

We have observed extragalactic sources Mrk421 (z=0.30) and H1426+428 (z=0.129) in very high energy gamma region using TACTIC telescope at Mount Abu, Rajasthan, India. Mrk421 was observed during 07 December 2005 to 18 April 2007 for a total…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-12 Kuldeep Yadav

A young and energetic pulsar powers the well-known Crab Nebula. Here we describe two separate gamma-ray (photon energy >100 MeV) flares from this source detected by the Large Area Telescope on board the Fermi Gamma-ray Space Telescope. The…

High Energy Astrophysical Phenomena · Physics 2011-01-11 LAT Collaboration

Mrk 501 is one of the brightest blazars at TeV energies and has been extensively studied since its first VHE detection in 1996. Our goal is to characterize in detail the source gamma-ray emission, together with the radio-to-X-ray emission,…

High Energy Astrophysical Phenomena · Physics 2015-06-23 MAGIC Collaboration , J. Aleksić , S. Ansoldi , L. A. Antonelli , P. Antoranz , A. Babic , P. Bangale , U. Barres de Almeida , J. A. Barrio , J. Becerra González , W. Bednarek , K. Berger , E. Bernardini , A. Biland , O. Blanch , R. K. Bock , S. Bonnefoy , G. Bonnoli , F. Borracci , T. Bretz , E. Carmona , A. Carosi , D. Carreto Fidalgo , P. Colin , E. Colombo , J. L. Contreras , J. Cortina , S. Covino , P. Da Vela , F. Dazzi , A. De Angelis , G. De Caneva , B. De Lotto , C. Delgado Mendez , M. Doert , A. Domínguez , D. Dominis Prester , D. Dorner , M. Doro , S. Einecke , D. Eisenacher , D. Elsaesser , E. Farina , D. Ferenc , M. V. Fonseca , L. Font , K. Frantzen , C. Fruck , R. J. García López , M. Garczarczyk , D. Garrido Terrats , M. Gaug , G. Giavitto , N. Godinović , A. González Muñoz , S. R. Gozzini , A. Hadamek , D. Hadasch , A. Herrero , D. Hildebrand , J. Hose , D. Hrupec , W. Idec , V. Kadenius , H. Kellermann , M. L. Knoetig , J. Krause , J. Kushida , A. La Barbera , D. Lelas , N. Lewandowska , E. Lindfors , S. Lombardi , M. López , R. López-Coto , A. López-Oramas , E. Lorenz , I. Lozano , M. Makariev , K. Mallot , G. Maneva , N. Mankuzhiyil , K. Mannheim , L. Maraschi , B. Marcote , M. Mariotti , M. Martínez , D. Mazin , U. Menzel , M. Meucci , J. M. Miranda , R. Mirzoyan , A. Moralejo , P. Munar-Adrover , D. Nakajima , A. Niedzwiecki , K. Nilsson , N. Nowak , R. Orito , A. Overkemping , S. Paiano , M. Palatiello , D. Paneque , R. Paoletti , J. M. Paredes , X. Paredes-Fortuny , S. Partini , M. Persic , F. Prada , P. G. Prada Moroni , E. Prandini , S. Preziuso , I. Puljak , R. Reinthal , W. Rhode , M. Ribó , J. Rico , J. Rodriguez Garcia , S. Rügamer , A. Saggion , T. Saito , K. Saito , M. Salvati , K. Satalecka , V. Scalzotto , V. Scapin , C. Schultz , T. Schweizer , S. N. Shore , A. Sillanpää , J. Sitarek , I. Snidaric , D. Sobczynska , F. Spanier , V. Stamatescu , A. Stamerra , T. Steinbring , J. Storz , S. Sun , T. Surić , L. Takalo , F. Tavecchio , P. Temnikov , T. Terzić , D. Tescaro , M. Teshima , J. Thaele , O. Tibolla , D. F. Torres , T. Toyama , A. Treves , M. Uellenbeck , P. Vogler , R. M. Wagner , F. Zandanel , R. Zanin , VERITAS Collaboration , : , B. Behera , M. Beilicke , W. Benbow , K. Berger , R. Bird , A. Bouvier , V. Bugaev , M. Cerruti , X. Chen , L. Ciupik , E. Collins-Hughes , W. Cui , C. Duke , J. Dumm , A. Falcone , S. Federici , Q. Feng , J. P. Finley , L. Fortson , A. Furniss , N. Galante , G. H. Gillanders , S. Griffin , S. T. Griffiths , J. Grube , G. Gyuk , D. Hanna , J. Holder , C. A. Johnson , P. Kaaret , M. Kertzman , D. Kieda , H. Krawczynski , M. J. Lang , A. S Madhavan , G. Maier , P. Majumdar , K. Meagher , P. Moriarty , R. Mukherjee , D. Nieto , A. O'Faoláin de Bhróithe , R. A. Ong , A. N. Otte , A. Pichel , M. Pohl , A. Popkow , H. Prokoph , J. Quinn , J. Rajotte , G. Ratliff , L. C. Reyes , P. T. Reynolds , G. T. Richards , E. Roache , G. H. Sembroski , K. Shahinyan , F. Sheidaei , A. W. Smith , D. Staszak , I. Telezhinsky , M. Theiling , J. Tyler , A. Varlotta , S. Vincent , S. P. Wakely , T. C. Weekes , R. Welsing , D. A. Williams , A. Zajczyk , B. Zitzer , External Collaborators , : , M. Villata , C. M. Raiteri , M. Ajello , M. Perri , H. D. Aller , M. F. Aller , V. M. Larionov , N. V. Efimova , T. S. Konstantinova , E. N. Kopatskaya , W. P. Chen , E. Koptelova , H. Y. Hsiao , O. M. Kurtanidze , M. G. Nikolashvili , G. N. Kimeridze , B. Jordan , P. Leto , C. S. Buemi , C. Trigilio , G. Umana , A. Lahtenmaki , E. Nieppola , M. Tornikoski , J. Sainio , V. Kadenius , M. Giroletti , A. Cesarini , L. Fuhrmann , Yu. A. Kovalev , Y. Y. Kovalev

Several strong TeV gamma-ray flares were detected from Markarian 421 in the years 2000 and 2001 by the Tibet III air shower array at a level of statistical significance of 5.1 sigma. Markarian 421 was unprecedentedly active at X-ray and TeV…

Astrophysics · Physics 2009-11-07 M. Amenomori

The ARGO-YBJ experiment is an extensive air shower array with full coverage RPC detectors located at Yangbajing (4300 m asl, Tibet, China). It is operated with high duty cycle (>86%) and a large field of view ($\sim$ 2sr). It continuously…

High Energy Astrophysical Phenomena · Physics 2019-08-14 Z. Cao , S. Z. Chen

Blazars are variable emitters across all wavelengths over a wide range of timescales, from months down to minutes. It is therefore essential to observe blazars simultaneously at different wavelengths, especially in the X-ray and gamma-ray…

High Energy Astrophysical Phenomena · Physics 2016-12-28 A. U. Abeysekara , S. Archambault , A. Archer , W. Benbow , R. Bird , M. Buchovecky , J. H. Buckley , V. Bugaev , J. V Cardenzana , M. Cerruti , X. Chen , L. Ciupik , M. P. Connolly , W. Cui , J. D. Eisch , A. Falcone , Q. Feng , J. P. Finley , H. Fleischhack , A. Flinders , L. Fortson , A. Furniss , S. Griffin , M. Hütten , N. Håkansson , D. Hanna , O. Hervet , J. Holder , T. B. Humensky , P. Kaaret , P. Kar , M. Kertzman , D. Kieda , M. Krause , S. Kumar , M. J. Lang , G. Maier , S. McArthur , A. McCann , K. Meagher , P. Moriarty , R. Mukherjee , D. Nieto , S. O'Brien , R. A. Ong , A. N. Otte , N. Park , V. Pelassa , M. Pohl , A. Popkow , E. Pueschel , K. Ragan , P. T. Reynolds , G. T. Richards , E. Roache , I. Sadeh , M. Santander , G. H. Sembroski , K. Shahinyan , D. Staszak , I. Telezhinsky , J. V. Tucci , J. Tyler , S. P. Wakely , A. Weinstein , A. Wilhelm , D. A. Williams , M. L. Ahnen , S. Ansoldi , L. A. Antonelli , P. Antoranz , C. Arcaro , 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 , R. Carosi , A. Carosi , A. Chatterjee , P. Colin , E. Colombo , J. L. Contreras , J. Cortina , S. Covino , P. Cumani , P. Da Vela , F. Dazzi , A. De Angelis , B. De Lotto , E. de Oña 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 , C. Fruck , D. Galindo , R. J. García López , M. Garczarczyk , M. Gaug , P. Giammaria , N. Godinović , D. Gora , D. Guberman , D. Hadasch , A. Hahn , T. Hassan , M. Hayashida , J. Herrera , J. Hose , D. Hrupec , G. Hughes , W. Idec , K. Kodani , Y. Konno , H. Kubo , J. Kushida , 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 , R. Mirzoyan , A. Moralejo , E. Moretti , D. Nakajima , V. Neustroev , A. Niedzwiecki , M. Nievas Rosillo , K. Nilsson , K. Nishijima , K. Noda , L. Nogués , M. Nöthe , 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 , J. R. Garcia , I. Reichardt , W. Rhode , M. Ribó , J. Rico , T. Saito , K. Satalecka , S. Schroeder , T. Schweizer , S. N. Shore , A. Sillanpää , J. Sitarek , I. Snidaric , D. Sobczynska , A. Stamerra , M. Strzys , T. Surić , L. Takalo , F. Tavecchio , P. Temnikov , T. Terzić , D. Tescaro , M. Teshima , D. F. Torres , N. Torres-Albà , T. Toyama , A. Treves , G. Vanzo , M. Vazquez Acosta , I. Vovk , J. E. Ward , M. Will , M. H. Wu , R. Zanin , T. Hovatta , I. de la Calle Perez , P. S. Smith , E. Racero , M. Baloković

Very high energy gamma-ray emission from the BL Lac object Markarian 421 has been detected over three observing seasons on 59 nights between April 1992 and June 1994 with the Whipple 10-meter imaging Cherenkov telescope. During its initial…

ARGO-YBJ is a full coverage air shower detector currently under construction at the Yangbajing Laboratory (4300 m a.s.l., Tibet, China). First data obtained with a subset of the apparatus will be available in summer 2003 while the full…

Astrophysics · Physics 2007-05-23 S. Vernetto , C. Bleve , T. Di Girolamo , G Di Sciascio , D. Martello

We report on the search for Gamma Ray Bursts (GRBs) in the energy range 1-100 GeV in coincidence with the prompt emission detected by satellites using the Astrophysical Radiation with Ground-based Observatory at YangBaJing (ARGO-YBJ) air…

High Energy Astrophysical Phenomena · Physics 2012-08-27 YBJ Collaboration , G. Aielli

We report results from a multi-wavelength monitoring campaign on Mrk 421 over the period of 2003-2004. The source was observed simultaneously at TeV and X-ray energies, with supporting observations frequently carried out at optical and…

Astrophysics · Physics 2008-11-26 M. Blazejowski

Blazars can be detected from very large distances due to their high luminosity. However, the detection of $\gamma$-ray emission of blazars beyond $z=3$ has only been confirmed for a small number of sources. Such observations probe the…

In this work, we report on the detection of enhanced TeV gamma- ray emission from the high synchrotron-peaked blazar Mrk 421 with the TACTIC telescope on the night of December 28, 2014 (MJD 57019). We use data from the TACTIC observations…