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Titel |
Spiky parallel electrostatic ion cyclotron and ion acoustic waves |
VerfasserIn |
R. V. Reddy, G. S. Lakhina, N. Singh, R. Bharuthram |
Medientyp |
Artikel
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Sprache |
Englisch
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ISSN |
1023-5809
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Digitales Dokument |
URL |
Erschienen |
In: Nonlinear Processes in Geophysics ; 9, no. 1 ; Nr. 9, no. 1, S.25-29 |
Datensatznummer |
250006596
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Publikation (Nr.) |
copernicus.org/npg-9-25-2002.pdf |
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Zusammenfassung |
One of the
interesting observations from the FAST satellite is the detection of
strong spiky waveforms in the parallel electric field in association with
ion cyclotron oscillations in the perpendicular electric fields. We report
here an analytical model of the coupled nonlinear ion cyclotron and
ion-acoustic waves, which could explain the observations. Using the fluid
equations for the plasma consisting of warm electrons and cold ions, a
nonlinear wave equation is derived in the rest frame of the propagating
wave for any direction of propagation oblique to the ambient magnetic
field. The equilibrium bulk flow of ions is also included in the model to
mimic the field-aligned current. Depending on the wave Mach number M
defined by M = V/Cs with V and Cs being
the wave phase velocity and ion-acoustic speed, respectively, we find a
range of solutions varying from a sinusoidal wave form for small
amplitudes and low M to sawtooth and highly spiky waveforms for nearly
parallel propagation. The results from the model are compared with the
satellite observations. |
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