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Title: Comment on “Existence domains of slow and fast ion-acoustic solitons in two-ion space plasmas” [Phys. Plasmas 22, 032313 (2015)]

Abstract

In a series of papers by Maharaj et al., including “Existence domains of slow and fast ion-acoustic solitons in two-ion space plasmas” [Phys. Plasmas 22, 032313 (2015)], incorrect expressions for the Sagdeev potential are presented. In this paper, we provide the correct expression of the Sagdeev potential. The correct expression was used to generate the numerical results for the above-mentioned series of papers, so that all results and conclusions are correct, despite the wrong Sagdeev potential expressions printed in the papers. The correct expression of the Sagdeev potential presented here is a very useful generic expression in the sense that a single expression can be used to study nonlinear structures associated with any acoustic mode, despite the fact that the supersonic and subsonic species would vary if solitons associated with different linear modes are studied.

Authors:
;  [1];  [2]
  1. South African National Space Agency (SANSA) Space Science, P. O. Box 32, Hermanus 7200 (South Africa)
  2. Department of Physics, University of the Western Cape, Robert Sobukwe Road, Bellville 7535 (South Africa)
Publication Date:
OSTI Identifier:
22600164
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 23; Journal Issue: 6; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; IONS; NONLINEAR PROBLEMS; PLASMA; POTENTIALS; SOLITONS; SPACE

Citation Formats

Olivier, C. P., E-mail: colivier@sansa.org.za, Maharaj, S. K., E-mail: smaharaj@sansa.org.za, E-mail: rbharuthram@uwc.ac.za, and Bharuthram, R., E-mail: rbharuthram@uwc.ac.za. Comment on “Existence domains of slow and fast ion-acoustic solitons in two-ion space plasmas” [Phys. Plasmas 22, 032313 (2015)]. United States: N. p., 2016. Web. doi:10.1063/1.4952639.
Olivier, C. P., E-mail: colivier@sansa.org.za, Maharaj, S. K., E-mail: smaharaj@sansa.org.za, E-mail: rbharuthram@uwc.ac.za, & Bharuthram, R., E-mail: rbharuthram@uwc.ac.za. Comment on “Existence domains of slow and fast ion-acoustic solitons in two-ion space plasmas” [Phys. Plasmas 22, 032313 (2015)]. United States. doi:10.1063/1.4952639.
Olivier, C. P., E-mail: colivier@sansa.org.za, Maharaj, S. K., E-mail: smaharaj@sansa.org.za, E-mail: rbharuthram@uwc.ac.za, and Bharuthram, R., E-mail: rbharuthram@uwc.ac.za. 2016. "Comment on “Existence domains of slow and fast ion-acoustic solitons in two-ion space plasmas” [Phys. Plasmas 22, 032313 (2015)]". United States. doi:10.1063/1.4952639.
@article{osti_22600164,
title = {Comment on “Existence domains of slow and fast ion-acoustic solitons in two-ion space plasmas” [Phys. Plasmas 22, 032313 (2015)]},
author = {Olivier, C. P., E-mail: colivier@sansa.org.za and Maharaj, S. K., E-mail: smaharaj@sansa.org.za, E-mail: rbharuthram@uwc.ac.za and Bharuthram, R., E-mail: rbharuthram@uwc.ac.za},
abstractNote = {In a series of papers by Maharaj et al., including “Existence domains of slow and fast ion-acoustic solitons in two-ion space plasmas” [Phys. Plasmas 22, 032313 (2015)], incorrect expressions for the Sagdeev potential are presented. In this paper, we provide the correct expression of the Sagdeev potential. The correct expression was used to generate the numerical results for the above-mentioned series of papers, so that all results and conclusions are correct, despite the wrong Sagdeev potential expressions printed in the papers. The correct expression of the Sagdeev potential presented here is a very useful generic expression in the sense that a single expression can be used to study nonlinear structures associated with any acoustic mode, despite the fact that the supersonic and subsonic species would vary if solitons associated with different linear modes are studied.},
doi = {10.1063/1.4952639},
journal = {Physics of Plasmas},
number = 6,
volume = 23,
place = {United States},
year = 2016,
month = 6
}
  • No abstract prepared.
  • A study of large amplitude ion-acoustic solitons is conducted for a model composed of cool and hot ions and cool and hot electrons. Using the Sagdeev pseudo-potential formalism, the scope of earlier studies is extended to consider why upper Mach number limitations arise for slow and fast ion-acoustic solitons. Treating all plasma constituents as adiabatic fluids, slow ion-acoustic solitons are limited in the order of increasing cool ion concentrations by the number densities of the cool, and then the hot ions becoming complex valued, followed by positive and then negative potential double layer regions. Only positive potentials are found formore » fast ion-acoustic solitons which are limited only by the hot ion number density having to remain real valued. The effect of neglecting as opposed to including inertial effects of the hot electrons is found to induce only minor quantitative changes in the existence regions of slow and fast ion-acoustic solitons.« less
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