The electromagnetic ion cyclotron instability in the Io torus

Journal Article · Fri Jul 01 04:00:00 EDT 1988 · Journal of Geophysical Research; (United States)

DOI:https://doi.org/10.1029/JA093iA07p07545· OSTI ID:5257071

Machida, S; Goertz, C K ^[1]; Hada, T ^[2]

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1. Univ. of Iowa, Iowa City (USA)
2. Univ. of California, Los Angeles (USA)

The electromagnetic ion cyclotron waves which are expected to exist in the Jovian magnetosphere are investigated. The temperature anisotropy generated by the inward radial diffusion of hot ions gives rise to an instability of L mode waves in the off-equatorial region of the Io torus. The resulting pitch angle scattering has been suggested as the cause for the precipitation of ions into the loss cone and auroral excitation. The linear wave dispersion is first examined, and the nonlinear wave amplitude for the saturated state is studied. Two estimates of the wave saturation level are checked by performing an electromagnetic hybrid simulation. Estimated nonlinear saturation amplitudes are compared with those resulting from linear amplification in a finite length. The result shows that the waves in the Jovian magnetosphere produced by the hot protons are mostly in a linear regime.

• OSTI ID: 5257071
• Journal Information: Journal of Geophysical Research; (United States), Journal Name: Journal of Geophysical Research; (United States) Vol. 93:A7; ISSN 0148-0227; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

640107* -- Astrophysics & Cosmology-- Planetary Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ANISOTROPY
ATMOSPHERES
AURORAE
CHARGED-PARTICLE PRECIPITATION
COMPARATIVE EVALUATIONS
DIFFUSION
DISPERSION RELATIONS
EVALUATION
ION WAVES
JUPITER PLANET
LOSS CONE
NONLINEAR PROBLEMS
PLANETARY ATMOSPHERES
PLANETARY MAGNETOSPHERES
PLANETS
PLASMA WAVES
SATELLITES