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arXiv · 1108.1514

Faraday rotation in the MOJAVE blazars: 3C 273 a case study

T. Hovatta·M. L. Lister·M. F. Aller·H. D. Aller·D. C. Homan·Y. Y. Kovalev·A. B Pushkarev·T. Savolainen
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Abstract

Radio polarimetric observations of Active Galactic Nuclei can reveal the magnetic field structure in the parsec-scale jets of these sources. We have observed the gamma-ray blazar 3C 273 as part of our multi-frequency survey with the Very Long Baseline Array to study Faraday rotation in a large sample of jets. Our observations re-confirm the transverse rotation measure gradient in 3C 273. For the first time the gradient is seen to cross zero which is further indication for a helical magnetic field and spine-sheath structure in the jet. We believe the difference to previous epochs is due to a different part of the jet being illuminated in our observations.

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T. Hovatta, M. L. Lister, M. F. Aller, H. D. Aller, D. C. Homan, Y. Y. Kovalev, A. B Pushkarev, T. Savolainen. 2011-08-06. Faraday rotation in the MOJAVE blazars: 3C 273 a case study. https://doi.org/10.1088/1742-6596%2F355%2F1%2F012008

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