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Title: On The Chaotic Dynamics Of Multiple Double Layers In Plasma

Abstract

When a multiple double layers structure in plasma is driven far from equilibrium, it passes into a chaotic state, characterized by uncorrelated oscillations of the plasma parameters. Two scenarios of transition to chaos were identified: the Feigenbaum scenario (cascade of period doubling bifurcations) and the intermittency scenario.

Authors:
; ; ;  [1]
  1. Faculty of Physics, 'Al. I. Cuza' University, 11 Carol I Blvd., 700506 Iasi (Romania)
Publication Date:
OSTI Identifier:
21057250
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 899; Journal Issue: 1; Conference: 6. international conference of the Balkan Physical Union, Istanbul (Turkey), 22-26 Aug 2006; Other Information: DOI: 10.1063/1.2733439; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; BIFURCATION; CHAOS THEORY; EQUILIBRIUM; LAYERS; OSCILLATIONS; PLASMA; PLASMA SHEATH; PLASMA WAVES

Citation Formats

Ivan, L. M., Chiriac, S. A., Aflori, M., and Dimitriu, D. G.. On The Chaotic Dynamics Of Multiple Double Layers In Plasma. United States: N. p., 2007. Web. doi:10.1063/1.2733439.
Ivan, L. M., Chiriac, S. A., Aflori, M., & Dimitriu, D. G.. On The Chaotic Dynamics Of Multiple Double Layers In Plasma. United States. doi:10.1063/1.2733439.
Ivan, L. M., Chiriac, S. A., Aflori, M., and Dimitriu, D. G.. Mon . "On The Chaotic Dynamics Of Multiple Double Layers In Plasma". United States. doi:10.1063/1.2733439.
@article{osti_21057250,
title = {On The Chaotic Dynamics Of Multiple Double Layers In Plasma},
author = {Ivan, L. M. and Chiriac, S. A. and Aflori, M. and Dimitriu, D. G.},
abstractNote = {When a multiple double layers structure in plasma is driven far from equilibrium, it passes into a chaotic state, characterized by uncorrelated oscillations of the plasma parameters. Two scenarios of transition to chaos were identified: the Feigenbaum scenario (cascade of period doubling bifurcations) and the intermittency scenario.},
doi = {10.1063/1.2733439},
journal = {AIP Conference Proceedings},
number = 1,
volume = 899,
place = {United States},
year = {Mon Apr 23 00:00:00 EDT 2007},
month = {Mon Apr 23 00:00:00 EDT 2007}
}
  • Experimental results are presented that reveal a complex route to chaos in plasma, in which a Feigenbaum scenario (cascade of temporal period-doubling bifurcation) develops simultaneously with a cascade of spatial period-doubling bifurcations, in connection with the appearance of a non-concentric multiple double layers structure. The Feigenbaum scenario is identified in the time series of the oscillations of the current through the plasma conductor.
  • Parametric characterization of multiple double layers is done during high pressure glow discharge in a toroidal vessel of small aspect ratio. Although glow discharge (without magnetic field) is known to be independent of device geometry, but the toroidal boundary conditions are conducive to plasma growth and eventually the plasma occupy the toroidal volume partially. At higher anode potential, the visibly glowing spots on the body of spatially extended anode transform into multiple intensely luminous spherical plasma blob structures attached to the tip of the positive electrode. Dynamics of multiple double layers are observed in argon glow discharge plasma in presencemore » of toroidal magnetic field. The radial profiles of plasma parameters measured at various toroidal locations show signatures of double layer formation in our system. Parametric dependence of double layer dynamics in presence of toroidal magnetic field is presented here.« less
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  • The properties of the electron beams that are produced by magnetized plasma double layers (which may reside in the auroral zone) are examined by means of particle-in-cell simulations, test particle simulations, and analytic theory. It is found that these beams are characterized by (1) a large degree of gyrophase bunching, (2) large T/sub perpendicular//T/sub parallel/ ratios, (3) very strong partialf/partialv/sub parallel/ gradients, and sometimes (4) a minimum in f(v/sub perpendicular/)/v/sub perpendicular/ near v/sub perpendicular/ = 0. The temporal modulation of the electron beams by the cyclic disruption and reformation of the magnetized double layers is quantified, and the disruption distancemore » of the sheet-shaped electron beams via the Langmuir waves that they drive is estimated. copyright American Geophysical Union 1988« less
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