Observation of Very High Energy γ-Rays from the AGN 1ES 2344+514 in a Low Emission State with the MAGIC Telescope

Albert, J.; Aliu, E.; Anderhub, H.; Antoranz, P.; Armada, A.; Baixeras, C.; Barrio, J. A.; Bartko, H.; Bastieri, D.; Becker, J. K.; Bednarek, W.; Berger, K.; Bigongiari, C.; Biland, A.; Bock, R. K.; Bordas, P.; Bosch-Ramon, V.; Bretz, T.; Britvitch, I.; Camara, M.; Carmona, E.; Chilingarian, A.; Ciprini, S.; Coarasa, J. A.; Commichau, S.; Contreras, J. L.; Cortina, J.; Costado, M. T.; Curtef, V.; Danielyan, V.; Dazzi, F.; De Angelis, A.; Delgado, C.; de los Reyes, R.; De Lotto, B.; Domingo-Santamaría, E.; Dorner, D.; Doro, M.; Errando, M.; Fagiolini, M.; De Angelis; Ferenc, D.; Fernández, E.; Firpo, R.; Flix, J.; Fonseca, M. V.; Font, L.; Fuchs, M.; Galante, N.; García-López, R.; Garczarczyk, M.; Gaug, M.; Giller, M.; Goebel, F.; Hakobyan, D.; Hayashida, M.; Hengstebeck, T.; Herrero, A.; Höhne, D.; Hose, J.; Hsu, C. C.; Jacon, P.; Jogler, T.; Kalekin, O.; Kosyra, R.; Kranich, D.; Kritzer, R.; Laille, A.; Liebing, P.; Lindfors, E.; Lombardi, S.; Longo, F.; López, J.; López, M.; Lorenz, E.; Majumdar, P.; Maneva, G.; Mannheim, K.; Mansutti, O.; Mariotti, M.; Martínez, M.; Mazin, D.; Merck, C.; Meucci, M.; Meyer, M.; Miranda, J. M.; Mirzoyan, R.; Mizobuchi, S.; Moralejo, A.; Nilsson, K.; Ninkovic, J.; Onña-Wilhelmi, E.; Otte, N.; Oya, I.; Paneque, D.; Panniello, M.; Paoletti, R.; Paredes, J. M.; Pasanen, M.; Pascoli, D. et al.
Bibliographical reference

The Astrophysical Journal, Volume 662, Issue 2, pp. 892-899.

Advertised on:
6
2007
Number of authors
145
IAC number of authors
5
Citations
65
Refereed citations
54
Description
The MAGIC collaboration has observed very high energy gamma-ray emission from the AGN 1ES 2344+514. A gamma-ray signal corresponding to an 11 σ excess and an integral flux of (2.38+/-0.30stat+/-0.70syst)×10-11 cm-2 s-1 above 200 GeV has been obtained from 23.1 hr of data taking between 2005 August 3 and 2006 January 1. The data confirm the previously detected gamma-ray emission from this object during a flare seen by the Whipple collaboration in 1995 and the evidence (below 5 σ significance level) from long-term observations conducted by the Whipple and HEGRA groups. The MAGIC observations show a relatively steep differential photon spectrum that can be described by a power law with a photon index of α=-2.95+/-0.12stat+/-0.2syst between 140 GeV and 5.4 TeV. The observations reveal a low-flux state, about 6 times below the 1995 flare seen by Whipple and comparable with the previous Whipple and HEGRA long-term measurements. During the MAGIC observations no significant time variability was observed.