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Title: Comparison of two approaches to the study of filamentation in plasmas

Abstract

This communication presents a comparison of two approaches to the study of filamentation in a plasma; viz., the study of the spatial growth of a sinusoidal instability, superposed on a uniform electromagnetic beam and the study of self-focusing of a Gaussian ripple, superposed on a uniform electromagnetic beam. The results of the two approaches have been expressed in a form whereby they can be compared and the similarities/differences highlighted. It has been pointed out that the growth of the instability in the first approach is equivalent to the self-focusing of the ripple in the second approach. The critical condition for the onset of the growth of a sinusoidal instability is seen to depend only on the irradiance of the main beam, while that for the self-focusing of the Gaussian ripple depends on the irradiance of the main beam, the irradiance of the ripple, and the phase difference between the two.

Authors:
;  [1]
  1. Ramanna Fellowship Programme, Department of Education Building, Lucknow University, Lucknow 226 007 (India)
Publication Date:
OSTI Identifier:
20974951
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 14; Journal Issue: 4; Other Information: DOI: 10.1063/1.2717884; (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; BEAMS; COMPARATIVE EVALUATIONS; ELECTROMAGNETIC RADIATION; INSTABILITY; PLASMA; RADIANT FLUX DENSITY

Citation Formats

Sodha, Mahendra Singh, and Sharma, Ashutosh. Comparison of two approaches to the study of filamentation in plasmas. United States: N. p., 2007. Web. doi:10.1063/1.2717884.
Sodha, Mahendra Singh, & Sharma, Ashutosh. Comparison of two approaches to the study of filamentation in plasmas. United States. doi:10.1063/1.2717884.
Sodha, Mahendra Singh, and Sharma, Ashutosh. Sun . "Comparison of two approaches to the study of filamentation in plasmas". United States. doi:10.1063/1.2717884.
@article{osti_20974951,
title = {Comparison of two approaches to the study of filamentation in plasmas},
author = {Sodha, Mahendra Singh and Sharma, Ashutosh},
abstractNote = {This communication presents a comparison of two approaches to the study of filamentation in a plasma; viz., the study of the spatial growth of a sinusoidal instability, superposed on a uniform electromagnetic beam and the study of self-focusing of a Gaussian ripple, superposed on a uniform electromagnetic beam. The results of the two approaches have been expressed in a form whereby they can be compared and the similarities/differences highlighted. It has been pointed out that the growth of the instability in the first approach is equivalent to the self-focusing of the ripple in the second approach. The critical condition for the onset of the growth of a sinusoidal instability is seen to depend only on the irradiance of the main beam, while that for the self-focusing of the Gaussian ripple depends on the irradiance of the main beam, the irradiance of the ripple, and the phase difference between the two.},
doi = {10.1063/1.2717884},
journal = {Physics of Plasmas},
number = 4,
volume = 14,
place = {United States},
year = {Sun Apr 15 00:00:00 EDT 2007},
month = {Sun Apr 15 00:00:00 EDT 2007}
}
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