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Title: Electrostatic coherent structures: The role of the ions dynamics

Abstract

The Vlasov-Poisson model is the basic framework for the investigation of electrostatic coherent structures (e.g., phase space holes). Directly observed by high resolution space instruments, they are considered as one of the key ingredients of collisionless space and laboratory plasmas. These structures are in general studied numerically in the 1D limit of nonmoving ions eventually leading to a one single final structure (vortex merging). Here we show that, despite the electronic nature of such vortex, the merging process is inhibited by the ions so that many structures are still observed after several ion periods. Furthermore, the ion mass cannot be considered just as a rescaling parameter in the system evolution. Finally, numerical discretization effects significantly influence the nonlinear plasma dynamics even if statistically the number and typical dimension of the structures is unchanged, thus making the results relevant to space observations.

Authors:
; ;  [1];  [2];  [3]
  1. Physics Department, University of Pisa (Italy) and LESIA, Observatoire de Paris-Meudon (France)
  2. (Italy)
  3. (France)
Publication Date:
OSTI Identifier:
20974976
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 14; Journal Issue: 5; Other Information: DOI: 10.1063/1.2724807; (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; BOLTZMANN-VLASOV EQUATION; IONS; NONLINEAR PROBLEMS; PHASE SPACE; PLASMA; PLASMA WAVES; POISSON EQUATION; VORTICES

Citation Formats

Califano, F., Galeotti, L., Briand, C., Physics Department, University of Pisa, and LESIA, Observatoire de Paris-Meudon. Electrostatic coherent structures: The role of the ions dynamics. United States: N. p., 2007. Web. doi:10.1063/1.2724807.
Califano, F., Galeotti, L., Briand, C., Physics Department, University of Pisa, & LESIA, Observatoire de Paris-Meudon. Electrostatic coherent structures: The role of the ions dynamics. United States. doi:10.1063/1.2724807.
Califano, F., Galeotti, L., Briand, C., Physics Department, University of Pisa, and LESIA, Observatoire de Paris-Meudon. Tue . "Electrostatic coherent structures: The role of the ions dynamics". United States. doi:10.1063/1.2724807.
@article{osti_20974976,
title = {Electrostatic coherent structures: The role of the ions dynamics},
author = {Califano, F. and Galeotti, L. and Briand, C. and Physics Department, University of Pisa and LESIA, Observatoire de Paris-Meudon},
abstractNote = {The Vlasov-Poisson model is the basic framework for the investigation of electrostatic coherent structures (e.g., phase space holes). Directly observed by high resolution space instruments, they are considered as one of the key ingredients of collisionless space and laboratory plasmas. These structures are in general studied numerically in the 1D limit of nonmoving ions eventually leading to a one single final structure (vortex merging). Here we show that, despite the electronic nature of such vortex, the merging process is inhibited by the ions so that many structures are still observed after several ion periods. Furthermore, the ion mass cannot be considered just as a rescaling parameter in the system evolution. Finally, numerical discretization effects significantly influence the nonlinear plasma dynamics even if statistically the number and typical dimension of the structures is unchanged, thus making the results relevant to space observations.},
doi = {10.1063/1.2724807},
journal = {Physics of Plasmas},
number = 5,
volume = 14,
place = {United States},
year = {Tue May 15 00:00:00 EDT 2007},
month = {Tue May 15 00:00:00 EDT 2007}
}
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