Symmetry breaking in a nonlinear αω-dynamo
- 1 June 1991
- journal article
- research article
- Published by Taylor & Francis in Geophysical & Astrophysical Fluid Dynamics
- Vol. 57 (1-4) , 147-189
- https://doi.org/10.1080/03091929108225233
Abstract
An idealized nonlinear αω-dynamo is investigated. Emphasis is placed upon the different spatial symmetries, and the asymmetries that arise after secondary bifurcations. On varying the main control parameter D (the dynamo number), many transitions are found involving solutions without an equatorial symmetry, and solutions with quasiperiodic time dependence, but no chaos. Instead of a cascade to smaller spatial scales when D is highly supercritical it is found that additional asymmetries are introduced at tertiary bifurcations. Our complete bifurcation diagrams allow us to follow in detail how stability is passed from one solution to another as D varies. In these diagrams there are typically multiple stable solutions at any value of D, which suggests that similar stars can have different magnetic patterns.Keywords
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