Discovery of Very High Energy Gamma Rays from 1ES 1218+30.4

The MAGIC collaboration has studied the high-frequency-peaked BL Lac object 1ES 1218+30.4, at a redshift z = 0.182, using the MAGIC imaging air Cerenkov telescope located on the Canary Island of La Palma. A gamma-ray signal was observed with 6.4 σ significance. The differential energy spectrum for an energy threshold of 120 GeV can be fitted by a simple power law, yielding FE(E) = (8.1 ± 2.1) × 10-7[E/(250 GeV)]-3.0±0.4 TeV-1 m-2 s-1. During the 6 days of observation in 2005 January, no time variability on timescales of days was found within the statistical errors. The observed integral flux above 350 GeV is nearly a factor of 2 below the upper limit reported by the Whipple collaboration in 2003.

Miguel Ángel Martínez | J. F. Molina | A. Chilingarian | A. Vardanyan | M. Fagiolini | K. Mase | W. Rhode | E. Fernández | M. Meucci | N. Turini | M. Pasanen | A. Angelis | B. Lotto | J. Flix | F. Pauss | K. Mannheim | H. Anderhub | A. Biland | H. Bartko | F. Goebel | R. Mirzoyan | M. Teshima | D. Paneque | S. Ciprini | F. Lucarelli | T. Wibig | T. Schweizer | J. Albert | F. Longo | S. Shore | T. Bretz | E. Bisesi | E. Lorenz | P. Sartori | I. Britvitch | W. Wittek | P. Majumdar | M. Gaug | M. Bartelt | O. Kalekin | C. Bigongiari | E. Aliu | M. Errando | N. Galante | M. Mariotti | F. Dazzi | P. Antoranz | C. Baixeras | J. Barrio | D. Bastieri | W. Bednarek | J. Contreras | J. Cortina | D. Dorner | M. Doro | D. Ferenc | L. Font | M. Hayashida | E. Lindfors | G. Maneva | D. Mazin | J. Miranda | N. Otte | I. Oya | M. Persic | E. Prandini | J. Rico | A. Saggion | V. Scalzotto | M. Shayduk | A. Sillanpää | D. Sobczynska | A. Stamerra | L. Takalo | P. Temnikov | D. Torres | H. Vankov | M. Garczarczyk | J. Hose | A. Moralejo | K. Nilsson | D. Tescaro | M. Meyer | A. Armada | M. Asensio | K. Berger | R. Bock | J. Coarasa | S. Commichau | V. Curtef | V. Danielyan | R. Reyes | E. Domingo-Santamarı́a | R. Firpo | M. Fonseca | M. Giller | D. Hakobyan | T. Hengstebeck | D. Höhne | P. Jacon | D. Kranich | A. Laille | J. Lopez | S. Mizobuchi | D. Pascoli | R. Pegna | L. Peruzzo | A. Piccioli | M. Rissi | A. Robert | S. Rügamer | R. Schmitt | N. Sidro | R. Wagner | J. Zapatero | P. Liebing | Francesco Longo | N. Tonello | R. Orduna | A. Torres | T. Lenisa | B. Riegel | N. Otte | S. R. Bavikadi | M. Poller | D. Hoehne | V. Vitale | F. Dazzi | R. Paoletti | L. Stark | E. OÑA-WILHELMI | R. Bavikadi | O. Kalekin | N. Pavel | K. Shinozaki | J. Pérez | M. Cámara | A. Sanchez | F. Gobel | M. López | W. Rhode | N. Sidro | M. Martinez | M. Meyer

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