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Title: Harmonic plasma waves excitation and structure evolution of intense ion beams in background plasmas

Abstract

The long-term dynamic evolutions of intense ion beams in plasmas have been investigated with two-dimensional electromagnetic particle simulations, taking into account the effect of the two-stream instability between beam ions and plasma electrons. Depending on the initial beam radial density profile and velocity distribution, ring structures may be formed in the beam edge regions. At the later stage of beam-plasma interactions, the ion beams are strongly modulated by the two-stream instability and multiple density spikes are formed in the longitudinal direction. The formation of these density spikes is shown to result from the excitation of harmonic plasma waves when the instability gets saturated. Comparisons between the beam cases with initial flat-top and Gaussian radial density profiles are made, and a higher instability growth rate is observed for the flat-top profile case.

Authors:
;  [1]
  1. School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)
Publication Date:
OSTI Identifier:
22599921
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; BEAM-PLASMA SYSTEMS; COMPARATIVE EVALUATIONS; DENSITY; DISTRIBUTION; ELECTRONS; EXCITATION; GAUSS FUNCTION; INSTABILITY GROWTH RATES; ION BEAMS; PLASMA WAVES; STREAMS; TWO-DIMENSIONAL CALCULATIONS; TWO-STREAM INSTABILITY

Citation Formats

Hu, Zhang-Hu, E-mail: zhanghu@dlut.edu.cn, and Wang, You-Nian. Harmonic plasma waves excitation and structure evolution of intense ion beams in background plasmas. United States: N. p., 2016. Web. doi:10.1063/1.4961083.
Hu, Zhang-Hu, E-mail: zhanghu@dlut.edu.cn, & Wang, You-Nian. Harmonic plasma waves excitation and structure evolution of intense ion beams in background plasmas. United States. doi:10.1063/1.4961083.
Hu, Zhang-Hu, E-mail: zhanghu@dlut.edu.cn, and Wang, You-Nian. 2016. "Harmonic plasma waves excitation and structure evolution of intense ion beams in background plasmas". United States. doi:10.1063/1.4961083.
@article{osti_22599921,
title = {Harmonic plasma waves excitation and structure evolution of intense ion beams in background plasmas},
author = {Hu, Zhang-Hu, E-mail: zhanghu@dlut.edu.cn and Wang, You-Nian},
abstractNote = {The long-term dynamic evolutions of intense ion beams in plasmas have been investigated with two-dimensional electromagnetic particle simulations, taking into account the effect of the two-stream instability between beam ions and plasma electrons. Depending on the initial beam radial density profile and velocity distribution, ring structures may be formed in the beam edge regions. At the later stage of beam-plasma interactions, the ion beams are strongly modulated by the two-stream instability and multiple density spikes are formed in the longitudinal direction. The formation of these density spikes is shown to result from the excitation of harmonic plasma waves when the instability gets saturated. Comparisons between the beam cases with initial flat-top and Gaussian radial density profiles are made, and a higher instability growth rate is observed for the flat-top profile case.},
doi = {10.1063/1.4961083},
journal = {Physics of Plasmas},
number = 8,
volume = 23,
place = {United States},
year = 2016,
month = 8
}
  • The transport of intense ion beams with sharp radial beam edge in plasmas has been studied with two-dimensional electromagnetic particle simulations. The initial solid beam evolves into a hollow beam due to the nonlinear sharp transverse force peak in the regions of beam edge. The magnitude and nonlinearity of this peak are enhanced as the ion beam travels further into the plasma, due to the self-consistent interactions between the beam ions and the plasma electrons. This structure formation is shown to be independent on the beam radius.
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