Field-line resonances in arbitrary magnetic field topology
Abstract
We present first results of a cold plasma field-line resonance model which can be utilized in arbitrary magnetic field topology. It turns out that for realistic magnetospheric magnetic fields there is no orthogonal coordinate system which is aligned everywhere with the background magnetic field. Therefore, a more general description based on covariant-contravariant formalism is required. We discuss the mathematical methods for computing the metric tensor coefficients required in this case and present the set of equations for covariant components of the perturbation electric and magnetic fields. An eigenvalue problem for these equations is solved numerically to compute the fundamental resonance frequency of a twisted magnetic field line and the results for several background field configurations are shown.
- Publication:
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AGU Spring Meeting Abstracts
- Pub Date:
- May 2004
- Bibcode:
- 2004AGUSMSM21B..06K
- Keywords:
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- 2704 Auroral phenomena (2407);
- 2740 Magnetospheric configuration and dynamics;
- 2752 MHD waves and instabilities;
- 7899 General or miscellaneous