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Key Problems of Flat Objects Dynamo Theory and Ways of Their Solution

Published online by Cambridge University Press:  19 July 2016

F. Krause
Affiliation:
Sternwarte Babelsberg Academy of Science Potsdam 1591 GDR
R. Meinel
Affiliation:
Sternwarte Babelsberg Academy of Science Potsdam 1591 GDR
D. Elstner
Affiliation:
Sternwarte Babelsberg Academy of Science Potsdam 1591 GDR
G. Rüdiger
Affiliation:
Sternwarte Babelsberg Academy of Science Potsdam 1591 GDR

Abstract

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The present status of galactic dynamo theory is discussed. A new concept which allows the determination of marginal dynamo numbers for axisymmetric as well as non-axisymmetric large-scale magnetic field modes in axisymmetric disks is applied to a simple galaxy model. The results obtained so far show that a preference of non-axisymmetric fields can only be expected if the α-effect is highly anisotropic and the differential rotation is not too strong. Mostly axisymmetric-spiral fields have to be expected.

Type
4. Magnetohydrodynamics of Galactic Magnetic Fields
Copyright
Copyright © Kluwer 1990 

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