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Magnetic Field Generation by Galactic Winds

Published online by Cambridge University Press:  19 July 2016

S.J. Spencer
Affiliation:
School of Physics, The University of Sydney, N.S.W. 2006, Australia
L.E. Cram
Affiliation:
School of Physics, The University of Sydney, N.S.W. 2006, Australia

Abstract

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A new mechanism is presented for the local amplification and possible global dynamo maintenance of non-axisymmetric large-scale magnetic fields in disk galaxies. Shear in a galactic wind or large-scale flow of ionised gas with components axial and radial to the disk plane may regenerate large-scale magnetic fields.

Numerical results are presented from kinematic mathematical models based on a local (thin disk) approximation and an exact three-dimensional formulation. The one-dimensional thin-disk model illustrates the possibility of exponential amplification and the resulting local axial spatial structure of large-scale galactic magnetic fields. Three-dimensional results support the possibility of global wind dynamo action.

Type
8. Magnetic Fields in Galaxies: Dynamo Theory
Copyright
Copyright © Kluwer 1993 

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