|
Titel |
Ponderomotive effects in magnetospheric hydromagnetic waves (*) |
VerfasserIn |
W. Allan, J. R. Manuel |
Medientyp |
Artikel
|
Sprache |
Englisch
|
ISSN |
0992-7689
|
Digitales Dokument |
URL |
Erschienen |
In: Annales Geophysicae ; 14, no. 9 ; Nr. 14, no. 9, S.893-905 |
Datensatznummer |
250012413
|
Publikation (Nr.) |
copernicus.org/angeo-14-893-1996.pdf |
|
|
|
Zusammenfassung |
The ponderomotive force (PMF) is a ubiquitous
nonlinear wave effect arising in plasma physics when applied wave fields or
plasma parameters have significant spatial gradients. Some basic properties of
the PMF are described as they relate to ULF hydromagnetic waves in the
magnetosphere. Examples are given of recent results obtained using both
analytical and numerical techniques for waves from the lowest frequencies
(determined by the dimensions of the magnetosphere) up to the vicinity of the
ion cyclotron frequency. These results include the possibilities that the PMF
may transport plasma over large distances in the magnetosphere, and that the PMF
may energize magnetospheric ions significantly. In particular the PMF may play a
role in transporting and energizing O+ ions from the ionosphere into
the body of the magnetosphere. The PMF can also generate nonlinear coupling
between the slow magnetosonic mode and the other hydromagnetic modes. This
should lead to limitation of density enhancements and, notably in the case of
standing Alfvén waves, to spatial harmonic generation, secularly growing
frequency shifts, and saturation of driven wave fields. Some implications of
these results for the magnetosphere are discussed. |
|
|
Teil von |
|
|
|
|
|
|