Observations of Markarian 421 with the MAGIC Telescope

The MAGIC telescope took data of very high energy gamma-ray emission from the blazar Markarian 421 ( Mrk 421) between 2004 November and 2005 April. We present a combined analysis of data samples recorded under different observational conditions, down to gamma- ray energies of 100 GeV. The flux was found to vary between 0.5 and 2 crab ( integrated above 200 GeV), considered a low state when compared to known data. Although the flux varied day by day, no short-term variability was observed, although there is some indication that not all nights show an equally quiescent state. The results at higher energies were found to be consistent with previous observations. A clear correlation is observed between gamma-ray and X-ray fluxes, whereas no significant correlation between gamma-ray and optical data is seen. The spectral energy distribution between 100 GeVand 3 TeV shows a clear deviation from a power law, more clearly and at lower flux than previous observations at higher energies. The deviation persists after correcting for the effect of attenuation by the extragalactic background light, and most likely is source- inherent. There is a rather clear indication of an inverse Compton peak around 100 GeV. The spectral energy distribution of Mrk 421 can be fitted by a one-zone synchrotron self-Compton model, suggesting once again a leptonic origin of the very high energy gamma-ray emission from this blazar.

Jose Flix | M. Garczarczyk | Denis Bastieri | Steven N. Shore | P. Temnikov | I. Oya | R. de los Reyes | E. Fernandez | I. Britvitch | A. De Angelis | Jelena Ninkovic | M. Errando | V. Scalzotto | Saverio Lombardi | P. Antoranz | A. Biland | Mario Meucci | Mario Martinez | O. Kalekin | E. Prandini | F. Pauss | Ll. Font | M. Poller | Josep M. Paredes | Razmik Mirzoyan | Michele Doro | W. Bednarek | K. Berger | E. Carmona | J. L. Contreras | J. Cortina | D. Ferenc | M. V. Fonseca | T. Jogler | G. Maneva | A. Moralejo | D. Paneque | M. Pasanen | L. Peruzzo | W. Rhode | J. Rico | A. Saggion | V. Scapin | T. Schweizer | M. Shayduk | D. Sobczynska | D. Tescaro | H. Vankov | R. Zanin | B. De Lotto | Alvaro Sanchez | Francesco Longo | D. Pascoli | M. Laatiaoui | N. Tonello | V. Danielyan | Justin Albert | C. Bigongiari | H. Bartko | A. Sillanpää | Karl Mannheim | O. Mansutti | Daniel Mazin | J. A. Barrio | J. Zapatero | R. Pegna | Antonio Stamerra | Ashot Chilingarian | T. Wibig | E. Lorenz | M. Meyer | Thomas Bretz | Daniela Dorner | Elina Lindfors | Kari Nilsson | Riccardo Paoletti | Massimo Persic | Marc Ribó | Masahiro Teshima | N. Otte | A. Chilingarian | O. Mansutti | M. Fagiolini | W. Rhode | E. Fernández | M. Meucci | R. Paoletti | N. Turini | V. Vitale | M. Pasanen | B. Lotto | J. Flix | F. Pauss | K. Mannheim | H. Anderhub | A. Biland | K. Shinozaki | H. Bartko | F. Goebel | R. Mirzoyan | M. Teshima | D. Paneque | S. Ciprini | T. Wibig | T. Schweizer | J. Ninković | J. Albert | C. Hsu | F. Longo | S. Shore | T. Bretz | E. Lorenz | P. Sartori | I. Britvitch | W. Wittek | P. Majumdar | M. Gaug | O. Kalekin | C. Bigongiari | E. Aliu | M. Errando | N. Galante | M. Mariotti | F. Dazzi | P. Antoranz | C. Baixeras | J. Barrio | D. Bastieri | W. Bednarek | P. Bordas | E. Carmona | J. Contreras | J. Cortina | D. Dorner | M. Doro | D. Ferenc | L. Font | M. Hayashida | T. Jogler | E. Lindfors | S. Lombardi | M. Lopez | G. Maneva | D. Mazin | J. Miranda | N. Otte | I. Oya | J. Paredes | M. Persic | E. Prandini | J. Rico | A. Saggion | V. Scalzotto | V. Scapin | M. Shayduk | A. Sillanpää | D. Sobczynska | A. Stamerra | L. Takalo | P. Temnikov | H. Vankov | R. Zanin | M. Garczarczyk | J. Hose | S. Lombardi | A. Moralejo | K. Nilsson | D. Tescaro | R. Wagner | V. Bosch-Ramon | M. Meyer | A. Armada | M. Asensio | J. Becker | K. Berger | R. Bock | J. Coarasa | S. Commichau | V. Curtef | V. Danielyan | R. Reyes | E. Domingo-Santamarı́a | R. Firpo | M. Fonseca | M. Fuchs | M. Giller | D. Hakobyan | T. Hengstebeck | D. Höhne | P. Jacon | R. Kosyra | D. Kranich | R. Kritzer | A. Laille | J. Lopez | M. Martínez | C. Merck | S. Mizobuchi | D. Pascoli | R. Pegna | L. Peruzzo | A. Piccioli | A. Raymers | M. Rissi | A. Robert | S. Rügamer | R. Schmitt | N. Sidro | L. S. Stark | J. Zapatero | M. Laatiaoui | A. De Angelis | B. De Lotto | Michela Fagiolini | M. Asensio | F. Dazzi | J. Hose | M. Mariotti | J. M. Miranda | C. Merck | Diego F. Torres | P. Liebing | Nicola Turini | Nicola Galante | M. Gaug | P. Majumdar | H. Anderhub | M. Camara | D. Kranich | M. Hayashida | E. Aliu | V. Vitale | C. C. Hsu | S. Mizobuchi | Maria Giller | W. Wittek | N. Tonello | D. Torres | R. Orduna | A. Sánchez | A. Torres | P. Liebing | M. Rissi | T. Bretz | A. Piccioli | C. Baixeras | S. Commichau | A. Laille | R. de los Reyes | K. Shinozaki | P. Sartori | M. Fuchs | A. Robert | Florian Goebel | T. Hengstebeck | R. Orduña | L. O. Takalo | Robert Wagner | Stefano Ciprini | M. López | E. Oña-Wilhelmi | R. Kosyra | A. Armada | J. K. Becker | R. Bock | Pol Bordas | Valentí Bosch-Ramon | Ja Coarasa | V. Curtef | E. Domingo-Santamaría | R. Firpo | D. Hakobyan | D. Höhne | P. Jacon | R. Kritzer | J. M. Lopez | A. Raymers | S. Rügamer | R. Schmitt | N. Sidro | A. Torres | M. Poller | M. Ribó | R. Paoletti | J. López | R. De Los Reyes | L. Stark | E. OÑA-WILHELMI | P. Jacoń | A. Sánchez | M. Cámara | J. Ninkovic | A. Sanchez | M. Ribó | A. D. Angelis | F. Longo | D. F. Torres | O. Mansutti | Mario Martinez | Masahiro Teshima | R. Wagner

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