Observations of the Blazar 3C 66A with the MAGIC Telescopes in Stereoscopic Mode

Abstract

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 $6^{\prime }$. The derived integral flux above $100\eh{GeV}$ is 8.3% of Crab Nebula flux and the energy spectrum is reproduced by a power law of photon index $3.64\pm 0.39_{\mathrm{stat}}\pm 0.25_{\mathrm{sys}}$. 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 $z<0.68$.

Accepted for publication in ApJ

References in corpus (9)

• VHE Gamma-Ray Observation of the Crab Nebula and its Pulsar with the MAGIC telescope
• Implementation of the Random Forest Method for the Imaging Atmospheric Cherenkov Telescope MAGIC
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Cited by in corpus (5)

• MAGIC discovery of VHE Emission from the FSRQ PKS 1222+21
• Quasi-periodic behaviour in the optical and γ-ray light curves of blazars 3C 66A and B2 1633+38
• Empirical multi-wavelength prediction method for very high energy gamma-ray emitting BL Lacs
• Discovery of very high energy gamma-ray emission from the blazar 1ES 0033+595 by the MAGIC telescopes
• Study of correlation between optical flux and polarization variations in BL Lac objects