Observations of the blazar 3C 66A with the magic telescopes in stereoscopic mode

We report new observations of the intermediate-frequency peaked BL Lacertae object 3C 66A with the MAGIC telescopes. The data sample we use were taken in 2009 December and 2010 January, and comprises 2.3 hr of good quality data in stereoscopic mode. In this period, we find a significant signal from...

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Bibliographic Details
Authors: Paredes i Poy, Josep Maria, Bordas Coma, Pol, Bosch i Ramon, Valentí, Ribó Gomis, Marc, Cañellas, A., Moldón Vara, Francisco Javier, Zabalza de Torres, Víctor
Format: article
Status:Published version
Publication Date:2011
Country:España
Institution:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repository:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:2445/122812
Online Access:https://hdl.handle.net/2445/122812
Access Level:Open access
Keyword:Galàxies actives
Raigs gamma
Active galaxies
Gamma rays
Description
Summary:We report new observations of the intermediate-frequency peaked BL Lacertae object 3C 66A with the MAGIC telescopes. The data sample we use were taken in 2009 December and 2010 January, and comprises 2.3 hr of good quality data in stereoscopic mode. In this period, we find a significant signal from the direction of the blazar 3C 66A. The new MAGIC stereoscopic system is shown to play an essential role for the separation between 3C 66A and the nearby radio galaxy 3C 66B, which is at a distance of only 6'. The derived integral flux above 100 GeV is 8.3% of the Crab Nebula flux and the energy spectrum is reproduced by a power law of photon index 3.64 ± 0.39stat ± 0.25sys. Within errors, this is compatible with the one derived by VERITAS in 2009. From the spectra corrected for absorption by the extragalactic background light, we only find small differences between the four models that we applied, and constrain the redshift of the blazar to z < 0.68.