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arXiv · 1502.07825

Polarization Swings Reveal Magnetic Energy Dissipation in Blazars

Haocheng Zhang·Xuhui Chen·Markus Boettcher·Fan Guo·Hui Li
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Abstract

The polarization signatures of the blazar emissions are known to be highly variable. In addition to small fluctuations of the polarization angle around a mean value, sometimes large (> 180^o) polarization angle swings are observed. We suggest that such p henomena can be interpreted as arising from light-travel-time effects within an underlying axisymmetric emission region. We present the first simultaneous fitting of the multi-wavelength spectrum, variability and time-dependent polarization features of a correlated optical and gamma-ray flaring event of the prominent blazar 3C279, which was accompanied by a drastic change of its polarization signatures. This unprecedented combination of spectral, variability, and polarization information in a coherent physical model allows us to place stringent constraints on the particle acceleration and magnetic-field topology in the relativistic jet of a blazar, strongly favoring a scenario in which magnetic energy dissipation is the primary driver of the flare event.

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Haocheng Zhang, Xuhui Chen, Markus Boettcher, Fan Guo, Hui Li. 2015-02-27. Polarization Swings Reveal Magnetic Energy Dissipation in Blazars. https://doi.org/10.1088/0004-637x%2F804%2F1%2F58

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