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Title: Density steepening formation in the interaction of microwave field with a plasma

Abstract

A modification of the electron density distribution of an unmagnetized plasma by the ponderomotive force of high-power microwave propagating into the plasma is studied. Using the Maxwell and fluid equations, nonlinear differential and integral equations for the electric field are obtained. The solution of these nonlinear equations shows that the profiles of the electric and magnetic field depart slightly from a sinusoidal shape, the amplitude of oscillations decreases in the plasma, and these oscillations become lengthened. Also, the period of oscillations decreases by increasing the microwave energy flux and the electron density becomes highly steepened for high microwave energy flux. Furthermore, the axial density profile shows a stationary density modulation that is phase-shifted with respect to the wave amplitude. This density modulation increases with the microwave energy flux.

Authors:
;  [1];  [2]
  1. Laser-Plasma Research Institute of Shahid Beheshti University, Evin, 1983963113 Tehran (Iran, Islamic Republic of) and Department of Physics and Laser-Plasma Research Institute of Shahid Beheshti University, Tehran (Iran, Islamic Republic of)
  2. (Iran, Islamic Republic of) and Research Institute Of Astronomy and Astrophysics Of Maragha, P. O. Box 55134-44, Maragha (Iran, Islamic Republic of)
Publication Date:
OSTI Identifier:
20974964
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 14; Journal Issue: 5; Other Information: DOI: 10.1063/1.2727483; (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; AMPLITUDES; ELECTRIC FIELDS; ELECTRON DENSITY; INTEGRAL EQUATIONS; MAGNETIC FIELDS; MAXWELL EQUATIONS; MICROWAVE RADIATION; MODULATION; NONLINEAR PROBLEMS; OSCILLATIONS; PHASE SHIFT; PLASMA; PLASMA DENSITY; PLASMA WAVES; PONDEROMOTIVE FORCE

Citation Formats

Niknam, A. R., Shokri, B., and Institute for Studies in Theoretical Physics and Mathematics, P. O. Box 19395-1795, Tehran. Density steepening formation in the interaction of microwave field with a plasma. United States: N. p., 2007. Web. doi:10.1063/1.2727483.
Niknam, A. R., Shokri, B., & Institute for Studies in Theoretical Physics and Mathematics, P. O. Box 19395-1795, Tehran. Density steepening formation in the interaction of microwave field with a plasma. United States. doi:10.1063/1.2727483.
Niknam, A. R., Shokri, B., and Institute for Studies in Theoretical Physics and Mathematics, P. O. Box 19395-1795, Tehran. Tue . "Density steepening formation in the interaction of microwave field with a plasma". United States. doi:10.1063/1.2727483.
@article{osti_20974964,
title = {Density steepening formation in the interaction of microwave field with a plasma},
author = {Niknam, A. R. and Shokri, B. and Institute for Studies in Theoretical Physics and Mathematics, P. O. Box 19395-1795, Tehran},
abstractNote = {A modification of the electron density distribution of an unmagnetized plasma by the ponderomotive force of high-power microwave propagating into the plasma is studied. Using the Maxwell and fluid equations, nonlinear differential and integral equations for the electric field are obtained. The solution of these nonlinear equations shows that the profiles of the electric and magnetic field depart slightly from a sinusoidal shape, the amplitude of oscillations decreases in the plasma, and these oscillations become lengthened. Also, the period of oscillations decreases by increasing the microwave energy flux and the electron density becomes highly steepened for high microwave energy flux. Furthermore, the axial density profile shows a stationary density modulation that is phase-shifted with respect to the wave amplitude. This density modulation increases with the microwave energy flux.},
doi = {10.1063/1.2727483},
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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