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arXiv · astro-ph/0308412

Polarization and kinematics in Cygnus A

Ilse M. van Bemmel·Joel Vernet·Robert A. E. Fosbury·Henny J. G. L. M. Lamers
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Abstract

From optical spectropolarimetry of Cygnus A we conclude that the scattering medium in the ionization cones in Cygnus A is moving outward at a speed of 170+-34 km/s, and that the required momentum can be supplied by the radiation pressure of an average quasar. Such a process could produce a structure resembling the observed ionization cones, which are thought to result from shadowing by a circumnuclear dust torus. We detect a polarized red wing in the [O III] emission lines arising from the central kiloparsec of Cygnus A. This wing is consistent with line emission created close to the boundary of the broad-line region.

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Ilse M. van Bemmel, Joel Vernet, Robert A. E. Fosbury, Henny J. G. L. M. Lamers. 2003-08-22. Polarization and kinematics in Cygnus A. https://doi.org/10.1046/j.1365-8711.2003.07141.x

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