Discovery of VHE gamma-ray emission from the BL Lacertae object B3 2247+381 with the MAGIC telescopes

Aleksic, J.; Alvarez, E. A.; Antonelli, L. A.; Antoranz, P.; Asensio, M.; Backes, M.; Barrio, J. A.; Bastieri, D.; Gonzalez, J. B.; Bednarek, W.; Berdyugin, A.; Berger, K.; Bernardini, E.; Biland, A.; Blanch, O.; Bock, R. K.; Boller, A.; Bonnoli, Giacomo; Tridon, D. B.; Braun, I.; Bretz, T.; Canellas, A.; Carmona, E.; Carosi, A.; Colin, P.; Colombo, E.; Contreras, J. L.; Cortina, J.; Cossio, L.; Covino, S.; Dazzi, F.; Angelis, A. D.; Caneva, G. D.; Del, E. D.; Lotto, B. D.; Mendez, C. D.; Ortega, A. D.; Doert, M.; Dominguez, A.; Prester, D. D.; Dorner, D.; Doro, M.; Elsaesser, D.; Ferenc, D.; Fonseca, M. V.; Font, L.; Fruck, C.; R. J. G.,; Garczarczyk, M.; Garrido, D.; Giavitto, G.; Godinovic, N.; Hadasch, D.; Hafner, D.; Herrero, A.; Hildebrand, D.; Hohne Monch, D.; Hose, J.; Hrupec, D.; Huber, B.; Jogler, T.; Kellermann, H.; Klepser, S.; Krahenbuhl, T.; Krause, J.; Barbera, A. L.; Lelas, D.; Leonardo, E.; Lindfors, E.; Lombardi, S.; Lopez, M.; Lopez Oramas, A.; Lorenz, E.; Makariev, M.; Maneva, G.; Mankuzhiyil, N.; Mannheim, K.; Maraschi, L.; Mariotti, M.; Martinez, M.; Mazin, D.; Meucci, M.; Miranda, J. M.; Mirzoyan, R.; Miyamoto, H.; Moldon, J.; Moralejo, A.; Munar Adrover, P.; Nieto, D.; Nilsson, K.; Orito, R.; Oya, I.; Paneque, D.; Paoletti, Riccardo; Pardo, S.; Paredes, J. M.; Partini, S.; Pasanen, M.; Pauss, F.; Perez Torres, M. A.; Persic, M.; Peruzzo, L.; Pilia, M.; Pochon, J.; Prada, F.; P. G. P.,; Prandini, E.; Puljak, I.; Reichardt, I.; Reinthal, R.; Rhode, W.; Ribo, M.; Rico, J.; Rugamer, S.; Saggion, A.; Saito, K.; Saito, T. Y.; Salvati, M.; Satalecka, K.; Scalzotto, V.; Scapin, V.; Schultz, C.; Schweizer, T.; Shayduk, M.; Shore, S. N.; Sillanpaa, A.; Sitarek, J.; Snidaric, I.; Sobczynska, D.; Spanier, F.; Spiro, S.; Stamatescu, V.; Stamerra, Antonio; Steinke, B.; Storz, J.; Strah, N.; Suric, T.; Takalo, L.; Takami, H.; Tavecchio, F.; Temnikov, P.; Terzic, T.; Tescaro, D.; Teshima, M.; Tibolla, O.; Torres, D. F.; Treves, A.; Uellenbeck, M.; Vankov, H.; Vogler, P.; Wagner, R. M.; Weitzel, Q.; Zabalza, V.; Zandanel, F.; Zanin, R.; Kadenius, V.; Weidinger, M.; Buson, S.

doi:10.1051/0004-6361/201117967

Aims. We study the non-thermal jet emission of the BL Lac object B3 2247+381 during a high optical state. Methods. The MAGIC telescopes observed the source during 13 nights between September 30th and October 30th 2010, collecting a total of 14.2 h of good quality very high energy (VHE) gamma-ray data. Simultaneous multiwavelength data was obtained with X-ray observations by the Swift satellite and optical R-band observations at the KVA-telescope. We also use high energy gamma-ray (HE, 0.1-100GeV) data from the Fermi satellite. Results. The BL Lac object B3 2247+381 (z = 0.119) was detected, for the first time, at VHE gamma-rays at a statistical significance of 5.6 sigma. A soft VHE spectrum with a photon index of -3.2 +/- 0.6 was determined. No significant short term flux variations were found. We model the spectral energy distribution using a one-zone SSC-model, which can successfully describe our data.

J., A., E. A., A., L. A., A., P., A., M., A., M., B., et al. (2012). Discovery of VHE gamma-ray emission from the BL Lacertae object B3 2247+381 with the MAGIC telescopes. ASTRONOMY & ASTROPHYSICS, 539 [10.1051/0004-6361/201117967].