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Title: Twisted electron-acoustic waves in plasmas

Abstract

In the paraxial limit, a twisted electron-acoustic (EA) wave is studied in a collisionless unmagnetized plasma, whose constituents are the dynamical cold electrons and Boltzmannian hot electrons in the background of static positive ions. The analytical and numerical solutions of the plasma kinetic equation suggest that EA waves with finite amount of orbital angular momentum exhibit a twist in its behavior. The twisted wave particle resonance is also taken into consideration that has been appeared through the effective wave number q{sub eff} accounting for Laguerre-Gaussian mode profiles attributed to helical phase structures. Consequently, the dispersion relation and the damping rate of the EA waves are significantly modified with the twisted parameter η, and for η → ∞, the results coincide with the straight propagating plane EA waves. Numerically, new features of twisted EA waves are identified by considering various regimes of wavelength and the results might be useful for transport and trapping of plasma particles in a two-electron component plasma.

Authors:
 [1];  [2]; ;  [3];  [4]
  1. Department of Nuclear Engineering, Pakistan Institute of Engineering and Applied Sciences (PIEAS), P. O. Nilore, Islamabad 45650 (Pakistan)
  2. (DPAM), Pakistan Institute of Engineering and Applied Sciences (PIEAS), P.O. Nilore, Islamabad 45650 (Pakistan)
  3. National Centre for Physics at Quaid-e-Azam University Campus, Shahdra Valley Road, Islamabad 44000 (Pakistan)
  4. Department of Physics and Applied Mathematics (DPAM), Pakistan Institute of Engineering and Applied Sciences (PIEAS), P.O. Nilore, Islamabad 45650 (Pakistan)
Publication Date:
OSTI Identifier:
22599876
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 23; Journal Issue: 8; 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; BOLTZMANN EQUATION; CATIONS; DISPERSION RELATIONS; ELECTRON PLASMA WAVES; ELECTRONS; GAUSS FUNCTION; LAGUERRE POLYNOMIALS; NUMERICAL SOLUTION; ORBITAL ANGULAR MOMENTUM; PARTICLES; PLASMA; TRANSPORT THEORY; TRAPPING

Citation Formats

Aman-ur-Rehman, E-mail: amansadiq@gmail.com, Department of Physics and Applied Mathematics, Ali, S., Khan, S. A., and Shahzad, K. Twisted electron-acoustic waves in plasmas. United States: N. p., 2016. Web. doi:10.1063/1.4961927.
Aman-ur-Rehman, E-mail: amansadiq@gmail.com, Department of Physics and Applied Mathematics, Ali, S., Khan, S. A., & Shahzad, K. Twisted electron-acoustic waves in plasmas. United States. doi:10.1063/1.4961927.
Aman-ur-Rehman, E-mail: amansadiq@gmail.com, Department of Physics and Applied Mathematics, Ali, S., Khan, S. A., and Shahzad, K. 2016. "Twisted electron-acoustic waves in plasmas". United States. doi:10.1063/1.4961927.
@article{osti_22599876,
title = {Twisted electron-acoustic waves in plasmas},
author = {Aman-ur-Rehman, E-mail: amansadiq@gmail.com and Department of Physics and Applied Mathematics and Ali, S. and Khan, S. A. and Shahzad, K.},
abstractNote = {In the paraxial limit, a twisted electron-acoustic (EA) wave is studied in a collisionless unmagnetized plasma, whose constituents are the dynamical cold electrons and Boltzmannian hot electrons in the background of static positive ions. The analytical and numerical solutions of the plasma kinetic equation suggest that EA waves with finite amount of orbital angular momentum exhibit a twist in its behavior. The twisted wave particle resonance is also taken into consideration that has been appeared through the effective wave number q{sub eff} accounting for Laguerre-Gaussian mode profiles attributed to helical phase structures. Consequently, the dispersion relation and the damping rate of the EA waves are significantly modified with the twisted parameter η, and for η → ∞, the results coincide with the straight propagating plane EA waves. Numerically, new features of twisted EA waves are identified by considering various regimes of wavelength and the results might be useful for transport and trapping of plasma particles in a two-electron component plasma.},
doi = {10.1063/1.4961927},
journal = {Physics of Plasmas},
number = 8,
volume = 23,
place = {United States},
year = 2016,
month = 8
}
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