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Polarimetric Properties of Blazars Caught by the WEBT

INAF, Osservatorio Astrofisico di Torino, via Osservatorio 20, I-10025 Pino Torinese, Italy
Author to whom correspondence should be addressed.
Academic Editors: Margo Aller, Jose L. Gómez and Eric Perlman
Galaxies 2021, 9(2), 42;
Received: 13 April 2021 / Revised: 8 June 2021 / Accepted: 10 June 2021 / Published: 11 June 2021
(This article belongs to the Special Issue Polarimetry as a Probe of Magnetic Fields in AGN Jets)
Active galactic nuclei come in many varieties. A minority of them are radio-loud, and exhibit two opposite prominent plasma jets extending from the proximity of the supermassive black hole up to megaparsec distances. When one of the relativistic jets is oriented closely to the line of sight, its emission is Doppler beamed and these objects show extreme variability properties at all wavelengths. These are called “blazars”. The unpredictable blazar variability, occurring on a continuous range of time-scales, from minutes to years, is most effectively investigated in a multi-wavelength context. Ground-based and space observations together contribute to give us a comprehensive picture of the blazar emission properties from the radio to the γ-ray band. Moreover, in recent years, a lot of effort has been devoted to the observation and analysis of the blazar polarimetric radio and optical behaviour, showing strong variability of both the polarisation degree and angle. The Whole Earth Blazar Telescope (WEBT) Collaboration, involving many tens of astronomers all around the globe, has been monitoring several blazars since 1997. The results of the corresponding data analysis have contributed to the understanding of the blazar phenomenon, particularly stressing the viability of a geometrical interpretation of the blazar variability. We review here the most significant polarimetric results achieved in the WEBT studies. View Full-Text
Keywords: active galactic nuclei; blazars; jets; polarimetry active galactic nuclei; blazars; jets; polarimetry
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MDPI and ACS Style

Raiteri, C.M.; Villata, M. Polarimetric Properties of Blazars Caught by the WEBT. Galaxies 2021, 9, 42.

AMA Style

Raiteri CM, Villata M. Polarimetric Properties of Blazars Caught by the WEBT. Galaxies. 2021; 9(2):42.

Chicago/Turabian Style

Raiteri, Claudia M., and Massimo Villata. 2021. "Polarimetric Properties of Blazars Caught by the WEBT" Galaxies 9, no. 2: 42.

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