Generation of high-frequency broadband electrostatic noise: The role of cold electrons

Journal Article · Mon Jun 01 04:00:00 EDT 1987 · Journal of Geophysical Research; (United States)

DOI:https://doi.org/10.1029/JA092iA06p05807· OSTI ID:5962689

Schriver, D; Ashour-Abdalla, M ^[1]

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1. Univ. of California, Los Angeles (United States)

Broadband electrostatic noise (BEN) is commonly observed in the plasma sheet boundary layer in association with ion beams. Here the authors investigate the generation of these waves in a plasma consisting of an ion beam and a background of hot ions, hot electrons, and cold electrons. The cold electrons are of ionospheric origin. A complete, systematic study of electrostatic ion beam instabilities, including cold electrons, has been done, and it is shown that for the plasma configuration described, four instabilities can be excited. These are the (1) ion acoustic, (2) Buneman, (3) beam resonant, and (4) electron acoustic instabilities. A low and high beam temperature division is shown to exist that separates when different instabilities can be excited. For typically observed parameters in the plasma sheet boundary layer, the ion beams lie in the high-temperature regime. In this regime, the beam resonant and electron acoustic instabilities are excited, and these instabilities can account for the high-frequency (> 500 Hz), low-power portion of the BEN spectrum. In the absence of cold electrons, no such wave growth occurs.

• OSTI ID: 5962689
• Journal Information: Journal of Geophysical Research; (United States), Journal Name: Journal of Geophysical Research; (United States) Vol. 92:A6; ISSN 0148-0227; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

661320* -- Auroral
Ionospheric
& Magnetospheric Phenomena-- (1992-)
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
BEAMS
BOUNDARY LAYERS
EARTH ATMOSPHERE
EARTH MAGNETOSPHERE
ELECTRIC FIELDS
ELECTRONS
ELEMENTARY PARTICLES
FERMIONS
INSTABILITY
ION BEAMS
IONOSPHERE
LANGMUIR FREQUENCY
LAYERS
LEPTONS
MAGNETOTAIL
ORIGIN
PLANETARY IONOSPHERES
PLASMA INSTABILITY
PLASMA SHEET
PLASMA WAVES