Simulation of collisionless electrostatic velocity-shear-driven instabilities

Journal Article · Fri Oct 01 04:00:00 EDT 1993 · Physics of Fluids B; (United States)

DOI:https://doi.org/10.1063/1.860847· OSTI ID:6190746

Pritchett, P L ^[1]

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1. Department of Physics and Institute of Geophysics and Planetary Physics, University of California, Los Angeles, California 90024-1547 (United States)

The properties of electrostatic instabilities in velocity shear layers in collisionless plasmas are investigated by means of two-dimensional particle simulations for the case where the ion gyroradius is comparable to the scale length of the velocity shear. For modes exactly perpendicular to the magnetic field, the Kelvin--Helmholtz instability dominates the evolution of the system producing [ital e][phi]/[ital T][sub [ital e]][gt]1; the observed growth rates show no reduction compared to the hydromagnetic limit. To obtain this result for the case of negative shear ([ital v][sub 0][ital y][sup [prime]]/[Omega][sub [ital i]][lt]0), it is necessary to include the kinetic modifications to the structure of the shear layer equilibrium. For finite [ital k][sub [parallel]] in the range 0[lt][ital k][sub [parallel]]/[ital k][lt]0.04, the shorter-wavelength inhomogeneous-energy-density-driven instability cannot be identified in the simulations, and the upper limit on its excitation is [ital e][phi]/[ital T][sub [ital e]][approx lt]2[times]10[sup [minus]3].

• OSTI ID: 6190746
• Journal Information: Physics of Fluids B; (United States), Journal Name: Physics of Fluids B; (United States) Vol. 5:10; ISSN 0899-8221; ISSN PFBPEI
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700330 -- Plasma Kinetics
Transport
& Impurities-- (1992-)
700340* -- Plasma Waves
Oscillations
& Instabilities-- (1992-)
COLLISIONLESS PLASMA
ELECTROSTATICS
HELMHOLTZ INSTABILITY
INSTABILITY
INSTABILITY GROWTH RATES
MAGNETOPAUSE
PLASMA
PLASMA INSTABILITY
PLASMA MACROINSTABILITIES
PLASMA SIMULATION
SHEAR
SIMULATION
SOLAR ACTIVITY
SOLAR WIND