ISEE 1 observations of electrostatic ion cyclotron waves in association with ion beams on auroral field lines from @ 2. 5 to 4. 5 R sub E

Journal Article · Mon Jul 01 04:00:00 EDT 1991 · Journal of Geophysical Research; (United States)

DOI:https://doi.org/10.1029/91JA00378· OSTI ID:5257077

Cattell, C A; Mozer, F S; Roth, I ^[1]; Anderson, R R ^[2]; Elphic, R C ^[3]; Lennartsson, W ^[4]; Ungstrup, E ^[5]

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1. Univ. of California, Berkeley (USA)
2. Univ. of Iowa, Iowa City (USA)
3. Univ. of California, Los Angeles (USA)
4. Lockheed Palo Alto Research Lab., CA (USA)
5. Danish Space Research Inst., Lyngby (Denmark)

Quasi-monochromatic waves at {approximately}1.2 f{sub cH}, where f{sub cH} is the hydrogen cyclotron frequency, were observed as the ISEE 1 satellite traversed auroral field lines at radial distances of {approximately}2.5 - 4.5 R{sub E} near midnight on June 19, 1981. The waves were polarized perpendicular to the magnetic field (k{sub {parallel}}/k{sub {perpendicular}} {le} 0.2). In addition, there were waves at slightly above both the helium and the oxygen cyclotron frequencies. The waves occurred within a region of reduced density ({approximately}0.1 - 0.2/cm{sup 3}) with the electron temperature greater than the ion temperature, upflowing hydrogen and oxygen beams, and weak field-aligned currents bounded by electrostatic shocks. The wave characteristics and associations were similar to those observed at lower altitudes by the S3-3 satellite. Comparisons were made between the observed H{sup +} and O{sup +} beams, field-aligned currents, densities and temperatures, and linear theories of electrostatic ion cyclotron waves and H{sup +}{minus}O{sup +} two-stream instabilities. The features of the observed waves are most consistent with the current-driven mode. In addition, numerical studies of the linear dispersion relation, using parameters based on the observations, showed that both the parallel and oblique two-stream modes and the ion-beam driven modes were stable while oblique current driven modes were unstable. The O{sup +} and H{sup +} distributions provide evidence for interactions with local electrostatic ion cyclotron waves and for the H{sup +}{minus}O{sup +} two-stream instability at altitudes below the satellite.

• OSTI ID: 5257077
• Journal Information: Journal of Geophysical Research; (United States), Journal Name: Journal of Geophysical Research; (United States) Vol. 96:A7; ISSN 0148-0227; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

640201* -- Atmospheric Physics-- Auroral
Ionospheric
& Magetospheric Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
AURORAL ZONES
BARYONS
BEAMS
CHARGED PARTICLES
COMPARATIVE EVALUATIONS
CURRENTS
CYCLOTRON FREQUENCY
DISTRIBUTION FUNCTIONS
ELECTRIC CURRENTS
ELECTRON DENSITY
ELECTRON TEMPERATURE
ELEMENTARY PARTICLES
EVALUATION
FERMIONS
FUNCTIONS
HADRONS
INSTABILITY
ION BEAMS
ION TEMPERATURE
ION WAVES
IONS
MATHEMATICS
NUCLEONS
NUMERICAL ANALYSIS
OXYGEN IONS
PLASMA INSTABILITY
PLASMA MICROINSTABILITIES
PLASMA WAVES
POLARIZATION
PROTONS
SATELLITES
TWO-STREAM INSTABILITY