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Title: Coulomb Clusters in Dusty Plasmas: Rotation and Stability

Abstract

Rotation and stability of dust clusters with different numbers (2 to 12) of micron-sized particles levitated in a horizontal plane was studied experimentally in inductively coupled magnetised dusty plasma. It was found that magnetic field has an influence on the cluster radius and its configuration producing a change in the confinement potential profile in plasma. In the experiment, dust particles have been confined over a flat unbiased electrode using magnetic field only. It was found that the fluctuating motion of the particles was dominated by its azimuthal component which was 2-12 times larger than radial component. It was also observed that the number of particles in a cluster strongly influenced the cluster instability. The reason behind certain cluster structures being more unstable than others was likely to be due to their number of possible metastable states.

Authors:
; ; ;  [1]
  1. School of Physics, University of Sydney, NSW 2006 (Australia)
Publication Date:
OSTI Identifier:
20726743
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 799; Journal Issue: 1; Conference: 4. international conference on the physics of dusty plasmas, Orleans (France), 13-17 Jun 2005; Other Information: DOI: 10.1063/1.2134596; (c) 2005 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; DUSTS; ELECTRODES; INSTABILITY; MAGNETIC FIELDS; METASTABLE STATES; PARTICLE SIZE; PARTICLES; PLASMA; PLASMA CONFINEMENT; POTENTIALS; ROTATION; STABILITY

Citation Formats

Cheung, F.M.H., Brunner, C., Samarian, A.A., and James, B.W.. Coulomb Clusters in Dusty Plasmas: Rotation and Stability. United States: N. p., 2005. Web. doi:10.1063/1.2134596.
Cheung, F.M.H., Brunner, C., Samarian, A.A., & James, B.W.. Coulomb Clusters in Dusty Plasmas: Rotation and Stability. United States. doi:10.1063/1.2134596.
Cheung, F.M.H., Brunner, C., Samarian, A.A., and James, B.W.. Mon . "Coulomb Clusters in Dusty Plasmas: Rotation and Stability". United States. doi:10.1063/1.2134596.
@article{osti_20726743,
title = {Coulomb Clusters in Dusty Plasmas: Rotation and Stability},
author = {Cheung, F.M.H. and Brunner, C. and Samarian, A.A. and James, B.W.},
abstractNote = {Rotation and stability of dust clusters with different numbers (2 to 12) of micron-sized particles levitated in a horizontal plane was studied experimentally in inductively coupled magnetised dusty plasma. It was found that magnetic field has an influence on the cluster radius and its configuration producing a change in the confinement potential profile in plasma. In the experiment, dust particles have been confined over a flat unbiased electrode using magnetic field only. It was found that the fluctuating motion of the particles was dominated by its azimuthal component which was 2-12 times larger than radial component. It was also observed that the number of particles in a cluster strongly influenced the cluster instability. The reason behind certain cluster structures being more unstable than others was likely to be due to their number of possible metastable states.},
doi = {10.1063/1.2134596},
journal = {AIP Conference Proceedings},
number = 1,
volume = 799,
place = {United States},
year = {Mon Oct 31 00:00:00 EST 2005},
month = {Mon Oct 31 00:00:00 EST 2005}
}
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