Langmuir turbulence in moderately magnetized space plasmas

Journal Article · Sun May 01 04:00:00 EDT 1994 · Physics of Plasmas; (United States)

DOI:https://doi.org/10.1063/1.870672· OSTI ID:6685824

Newman, D L; Goldman, M V ^[1]; Ergun, R E ^[2]

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1. APAS Department, University of Colorado, Boulder, Colorado 80309-0391 (United States)
2. Space Sciences Laboratory, University of California, Berkeley, California 94720 (United States)

Beam-driven Langmuir turbulence is studied in two moderately magnetized ([Omega][sub [ital e]][approx][omega][sub [ital e]]) space-plasma regimes: regions of the lower solar corona and the Earth's auroral ionosphere. The turbulence is modeled using modified Zakharov equations, which are employed in two-dimensional numerical simulations. For coronal parameters, highly anisotropic coherent wave packets form and collapse when [Omega][sub [ital e]][lt][omega][sub [ital e]]. By contrast, the turbulence is phase incoherent when [Omega][sub [ital e]][gt][omega][sub [ital e]], as a result of change in the topology of the Langmuir dispersion relation. In the auroral ionosphere, intense Langmuir waves (up to 500 mV/m) have been measured, in conjunction with field-aligned electron streams and nonthermal electron tails. Approximate agreement with high-time-resolution electric-field measurements, is found in the simulations. However, because of strong damping on nonthermal electrons, wave collapse is inhibited, irrespective of the ordering of [Omega][sub [ital e]] and [omega][sub [ital e]].

• OSTI ID: 6685824
• Journal Information: Physics of Plasmas; (United States), Journal Name: Physics of Plasmas; (United States) Vol. 1:5; ISSN PHPAEN; ISSN 1070-664X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700340* -- Plasma Waves
Oscillations
& Instabilities-- (1992-)
700370 -- Plasma Fluid & MHD Properties-- (1992-)
ATMOSPHERES
AURORAL ZONES
BEAMS
DISPERSION RELATIONS
EARTH ATMOSPHERE
ELECTRON BEAMS
IONOSPHERE
LEPTON BEAMS
MAGNETIC FIELD CONFIGURATIONS
MATHEMATICS
PARTICLE BEAMS
PLANETARY IONOSPHERES
PLASMA SIMULATION
SIMULATION
SOLAR ATMOSPHERE
SOLAR CORONA
STELLAR ATMOSPHERES
STELLAR CORONAE
TOPOLOGY
TURBULENCE
WAVE PACKETS