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Title: Gas acoustic and ion acoustic waves in partially ionized plasmas with magnetized electrons

Abstract

The properties of gas acoustic and ion acoustic modes are investigated in a collisional, weakly ionized plasma in the presence of unmagnetized ions and magnetized electrons. In such a plasma, an ion acoustic mode, driven by an electron flow along the magnetic field lines, can propagate almost at any angle with respect to the ambient field lines as long as the electrons are capable of participating in the perturbations by moving only along the field lines. Several effects, including the electron-ion collisions, the perturbations of the neutral gas, and the electromagnetic perturbations, are studied in the present work. The electron-ion collisions are shown to modify the previously obtained angle-dependent instability threshold for the driving electron flow. The inclusion of the neutral dynamics implies an additional neutral sound mode, which couples to the current driven ion acoustic mode, and these two modes can interchange their identities in certain parameter regimes. The electromagnetic effects, which in the present model imply a bending of the magnetic field lines, result in a further destabilization of an already unstable ion acoustic wave. The applicability of these results to the solar and/or space and laboratory plasmas is discussed.

Authors:
; ;  [1];  [2];  [3]
  1. Center for Plasma Astrophysics, Celestijnenlaan 200B, 3001 Leuven (Belgium)
  2. (Australia)
  3. (Belgium)
Publication Date:
OSTI Identifier:
20974865
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 14; Journal Issue: 3; Other Information: DOI: 10.1063/1.2710796; (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; DISTURBANCES; ELECTROMAGNETIC RADIATION; ELECTRON GAS; ELECTRON-ION COLLISIONS; ELECTRONS; ION ACOUSTIC WAVES; IONS; MAGNETIC FIELDS; PLASMA; PLASMA INSTABILITY

Citation Formats

Vranjes, J., Pandey, B. P., Poedts, S., Department of Physics, Macquarie University, Sydney, NSW 2109, and Center for Plasma Astrophysics, Celestijnenlaan 200B, 3001 Leuven. Gas acoustic and ion acoustic waves in partially ionized plasmas with magnetized electrons. United States: N. p., 2007. Web. doi:10.1063/1.2710796.
Vranjes, J., Pandey, B. P., Poedts, S., Department of Physics, Macquarie University, Sydney, NSW 2109, & Center for Plasma Astrophysics, Celestijnenlaan 200B, 3001 Leuven. Gas acoustic and ion acoustic waves in partially ionized plasmas with magnetized electrons. United States. doi:10.1063/1.2710796.
Vranjes, J., Pandey, B. P., Poedts, S., Department of Physics, Macquarie University, Sydney, NSW 2109, and Center for Plasma Astrophysics, Celestijnenlaan 200B, 3001 Leuven. Thu . "Gas acoustic and ion acoustic waves in partially ionized plasmas with magnetized electrons". United States. doi:10.1063/1.2710796.
@article{osti_20974865,
title = {Gas acoustic and ion acoustic waves in partially ionized plasmas with magnetized electrons},
author = {Vranjes, J. and Pandey, B. P. and Poedts, S. and Department of Physics, Macquarie University, Sydney, NSW 2109 and Center for Plasma Astrophysics, Celestijnenlaan 200B, 3001 Leuven},
abstractNote = {The properties of gas acoustic and ion acoustic modes are investigated in a collisional, weakly ionized plasma in the presence of unmagnetized ions and magnetized electrons. In such a plasma, an ion acoustic mode, driven by an electron flow along the magnetic field lines, can propagate almost at any angle with respect to the ambient field lines as long as the electrons are capable of participating in the perturbations by moving only along the field lines. Several effects, including the electron-ion collisions, the perturbations of the neutral gas, and the electromagnetic perturbations, are studied in the present work. The electron-ion collisions are shown to modify the previously obtained angle-dependent instability threshold for the driving electron flow. The inclusion of the neutral dynamics implies an additional neutral sound mode, which couples to the current driven ion acoustic mode, and these two modes can interchange their identities in certain parameter regimes. The electromagnetic effects, which in the present model imply a bending of the magnetic field lines, result in a further destabilization of an already unstable ion acoustic wave. The applicability of these results to the solar and/or space and laboratory plasmas is discussed.},
doi = {10.1063/1.2710796},
journal = {Physics of Plasmas},
number = 3,
volume = 14,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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