Galactic dynamo models without sharp boundaries
- 1 January 1990
- journal article
- research article
- Published by Taylor & Francis in Geophysical & Astrophysical Fluid Dynamics
- Vol. 50 (1-3) , 85-94
- https://doi.org/10.1080/03091929008219874
Abstract
A new numerical approach is introduced which allows investigation into the conditions for dynamogeneration of axisymmetric and non-axisymmetric large-scale magnetic field modes in galaxy models which are defined by axisymmetric distributions of the α-parameter, the angular velocity and the electrical conductivity. The velocity field is assumed to be localized, however, the common assumption of a sharp boundary of the conducting region is dropped. The possible anisotropy of the α-tensor is taken into account. The critical dynamo numbers (excitation conditions) for different modes are obtained by a direct method. The required steady states are attained by the use of an artificial non-linearity. Initial test calculations demonstrate the efficacy of this new concept.Keywords
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