Parsec-Scale Jets in Active Galactic Nuclei

  • Denise C. GabuzdaEmail author
Part of the Astrophysics and Space Science Library book series (ASSL, volume 414)


Considerable progress has been made over the past decade or so in understanding the jets of Active Galactic Nuclei on the parsec scales probed by Very Long Baseline Interferometry. The availability of multi-wavelength polarization VLBI observations for relatively large samples of objects for the first time has provided fundamental new information about the spectral indices and Faraday rotation measures in the core and jet components. Reliable estimates of the core magnetic fields and degrees of circular polarization have also become available for the first time. The jets exhibit complex behaviour, such as accelerations and non-radial motions of individual moving features, and even swings of the jet as a whole. New approaches have been developed to estimate the intrinsic speeds and viewing angles of the jets. A variety of new evidence seems to be suggesting that many of the properties we are observing are a consequence of helical magnetic fields carried outward by the jets, which should come about naturally due to the rotation of the central black hole and its accretion disk together with the jet outflow.


Circular Polarization Very Long Baseline Interferometry Active Galactic Nucleus Faraday Rotation Very Long Baseline Interferometry Observation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



This review has made use of data from the MOJAVE database that is maintained by the MOJAVE team (Lister et al., 2009, AJ, 137, 3718). The image used to compose Fig. 5.4 was taken from the MOJAVE website,


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© Springer International Publishing Switzerland 2015

Authors and Affiliations

  1. 1.Department of PhysicsUniversity College CorkCorkIreland

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