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Title: Particle-in-cell simulations of ion-acoustic waves with application to Saturn's magnetosphere

Abstract

Using a particle-in-cell simulation, the dispersion and growth rate of the ion-acoustic mode are investigated for a plasma containing two ion and two electron components. The electron velocities are modelled by a combination of two kappa distributions, as found in Saturn's magnetosphere. The ion components consist of adiabatic ions and an ultra-low density ion beam to drive a very weak instability, thereby ensuring observable waves. The ion-acoustic mode is explored for a range of parameter values such as κ, temperature ratio, and density ratio of the two electron components. The phase speed, frequency range, and growth rate of the mode are investigated. Simulations of double-kappa two-temperature plasmas typical of the three regions of Saturn's magnetosphere are also presented and analysed.

Authors:
 [1];  [2]; ;  [3];  [1]
  1. South African National Space Agency (SANSA), Space Science, Hermanus (South Africa)
  2. (KTH), Stockholm (Sweden)
  3. School of Chemistry and Physics, University of KwaZulu-Natal, Durban (South Africa)
Publication Date:
OSTI Identifier:
22300252
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 21; Journal Issue: 7; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; ELECTRONS; FREQUENCY RANGE; ION DENSITY; PLASMA; SATURN PLANET; SIMULATION; SOUND WAVES

Citation Formats

Koen, Etienne J., School of Electrical Engineering, Royal Institute of Technology, Collier, Andrew B., Hellberg, Manfred A., and Maharaj, Shimul K.. Particle-in-cell simulations of ion-acoustic waves with application to Saturn's magnetosphere. United States: N. p., 2014. Web. doi:10.1063/1.4891320.
Koen, Etienne J., School of Electrical Engineering, Royal Institute of Technology, Collier, Andrew B., Hellberg, Manfred A., & Maharaj, Shimul K.. Particle-in-cell simulations of ion-acoustic waves with application to Saturn's magnetosphere. United States. doi:10.1063/1.4891320.
Koen, Etienne J., School of Electrical Engineering, Royal Institute of Technology, Collier, Andrew B., Hellberg, Manfred A., and Maharaj, Shimul K.. Tue . "Particle-in-cell simulations of ion-acoustic waves with application to Saturn's magnetosphere". United States. doi:10.1063/1.4891320.
@article{osti_22300252,
title = {Particle-in-cell simulations of ion-acoustic waves with application to Saturn's magnetosphere},
author = {Koen, Etienne J. and School of Electrical Engineering, Royal Institute of Technology and Collier, Andrew B. and Hellberg, Manfred A. and Maharaj, Shimul K.},
abstractNote = {Using a particle-in-cell simulation, the dispersion and growth rate of the ion-acoustic mode are investigated for a plasma containing two ion and two electron components. The electron velocities are modelled by a combination of two kappa distributions, as found in Saturn's magnetosphere. The ion components consist of adiabatic ions and an ultra-low density ion beam to drive a very weak instability, thereby ensuring observable waves. The ion-acoustic mode is explored for a range of parameter values such as κ, temperature ratio, and density ratio of the two electron components. The phase speed, frequency range, and growth rate of the mode are investigated. Simulations of double-kappa two-temperature plasmas typical of the three regions of Saturn's magnetosphere are also presented and analysed.},
doi = {10.1063/1.4891320},
journal = {Physics of Plasmas},
number = 7,
volume = 21,
place = {United States},
year = {Tue Jul 15 00:00:00 EDT 2014},
month = {Tue Jul 15 00:00:00 EDT 2014}
}
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