MAGIC observations and multifrequency properties of the flat spectrum radio quasar 3C 279 in 2011
: Aeksic J, Ansoldi S, Antonelli LA, Antoranz P, Babie A, Bangale P, de Almeida EB, Barrio JA, Gonzalez JB, Bednarek W, Berger K, Bernardini E, Biland A, Bianch O, Bock RK, Bonnefoy S, Bormoli G, Borracci F, Bretz T, Carmona E, Carosi A, Fidalgo DC, Colin P, Colombo E, Contreras JL, Cortina J, Covino S, Da Vela P, Dazzi F, De Angelis A, De Caneva G, De Lotto B, Mendez CD, Doert M, Dominguez A, Presters DD, Dorner D, Doro M, Einecke S, Eisenacher D, Elsaesser D, Farina E, Ferenc D, Fonseca MV, Font L, Frantzen K, Fruck C, Lopez RJG, Garczarczyki M, Terrats DG, Gaug M, Giavitto G, Godinovic N, Munoz AG, Gozzini SR, Hadasch D, Herrero A, Hildebrand D, Hose J, Hrupec D, Idec W, Kadenius V, Kellermann H, Knoetig ML, Kodani K, Konno Y, Krause J, Kubo H, Kushida J, La Barbera A, Lelas D, Lewandowska N, Lindfors E, Lombardi S, Lopez M, Lopez-Coto R, Lopez-Oramas A, Lorenz U, Lozano I, Makariev M, Mallot K, Maneva G, Mankuzhiyil N, Mannheim K, Maraschi L, Mareote B, Mariotti M, Martinez M, Mazin D, Menzel U, Meucci M, Miranda JM, Mirzoyan R, Moralejo A, Munar-Adrover P, Nakajima D, Niedzwiecki A, Niisson K, Nishijima K, Nowak N, Orito R, Overkemping A, Paiano S, Palatiello M, Paneque D, Paoletti R, Paredes JM, Paredes-Fortuny X, Partini S, Persic M, Prada F, Moroni PGP, Prandini E, Preziuso S, Puljak I, Reinthal R, Rhode W, Ribo M, Rico J, Garcia JR, Rugamer S, Saggion A, Saito T, Saito K, Salvati M, Satalecka K, Scalzotto V, Seapin V, Schultz C, Schweizer T, Shore SN, Sillanpaa A, Sitarek J, Snidarie I, Sobczynska D, Spanier F, Stamatescu V, Stamerra A, Steinbring T, Storz J, Sun S, Suric T, Takalo L, Takarni H, Taveeehio F, Temnikov P, Terzic T, Tescaro D, Teshima M, Thaele J, Tibolla O, Torres DF, Toyama T, Treves A, Vogler P, Wagner RM, Zandane F, Zanin R, Berdyugin A, Vornanen T, Lahbteenmaki A, Tammi J, Tornikoski M, Hovatta T, Max-Moerbeek W, Readhead A, Richards J, Hayashida M, Sanehez DA, Marscher A, Jorstad S
Publisher: EDP SCIENCES S A
: 2014
: Astronomy and Astrophysics
: ASTRONOMY & ASTROPHYSICS
: ASTRON ASTROPHYS
: UNSP A41
: 567
: 14
: 0004-6361
DOI: https://doi.org/10.1051/0004-6361/201323036
Results. During the MAGIC observations (2011 February 8 to April 11) 3C 279 was in a low state in optical, X-ray, and gamma-rays. The MAGIC observations did not yield a significant detection. The derived upper limits are in agreement with the extrapolation of the HE gamma-ray spectrum, corrected for EBL absorption, from Fermi-LAT. The second part of the MAGIC observations in 2011 was triggered by a high-activity state in the optical and gamma-ray bands. During the optical outburst the optical electric vector position angle (EVPA) showed a rotation of similar to 180 degrees. Unlike previous cases, there was no simultaneous rotation of the 43 GHz radio polarisation angle. No VHE gamma-rays were detected by MAGIC, and the derived upper limits suggest the presence of a spectral break or curvature between the Fermi-LAT and MAGIC bands. The combined upper limits are the strongest derived to date for the source at VHE and below the level of the previously detected flux by a factor of similar to 2. Radiation models that include synchrotron and inverse Compton emissions match the optical to gamma-ray data, assuming an emission component inside the broad line region with size R = 1.1 x 10(16) cm and magnetic field B = 1.45 G responsible for the high-energy emission, and another one outside the broad line region and the infrared torus (R = 1.5 x 10(17) cm and B = 0.8 G) causing the optical and low-energy emission. We also study the optical polarisation in detail and interpret it with a bent trajectory model.
