SHEAR LANGMUIR VORTEX - AN ELEMENTARY MODE OF PLASMA COLLECTIVE BEHAVIOR

Citation
Ad. Rogava et al., SHEAR LANGMUIR VORTEX - AN ELEMENTARY MODE OF PLASMA COLLECTIVE BEHAVIOR, Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics, 57(6), 1998, pp. 7103-7110
Citations number
28
Categorie Soggetti
Physycs, Mathematical","Phsycs, Fluid & Plasmas
ISSN journal
1063651X
Volume
57
Issue
6
Year of publication
1998
Pages
7103 - 7110
Database
ISI
SICI code
1063-651X(1998)57:6<7103:SLV-AE>2.0.ZU;2-1
Abstract
Linear evolution of electrostatic perturbations in a cold, unmagnetize d, two-component plasma with shear flow is studied. It is shown that t he velocity shear induces, due to the non-normality of the linear dyna mics, a new elementary mode of plasma nonperiodic collective behavior- the ''shear Langmuir vortex.'' The mode, characterized by intense ener gy exchange with the mean flow, is associated with nonoscillatory moti on of the plasma species. In the low-shear limit, the vortex patterns can be described by extremely simple analytic solutions both for the t wo-dimensional and three-dimensional cases. It is shown that the two-d imensional vortices are able to extract the mean flow energy only tran siently, while the three-dimensional structures can grow asymptoticall y. In moderate and high shear regimes, the conversion of shear Langmui r vortexes into Langmuir oscillations becomes possible; the latter has nonresonant character and happens abruptly in time.