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Title: Computationally efficient description of relativistic electron beam transport in collisionless plasma

Abstract

A reduced approach to modeling the electromagnetic Weibel instability and relativistic electron beam transport in collisionless background plasma is developed. Beam electrons are modeled by macroparticles and the background plasma is represented by electron fluid. Conservation of generalized vorticity and quasineutrality of the plasma-beam system are used to simplify the governing equations. The method is suitable for modeling the nonlinear stages of collisionless beam-plasma interaction. A computationally efficient code based on this reduced description is developed and benchmarked against a standard particle-in-cell code. The full-scale two-dimensional numerical simulation of the Weibel instability saturation of a low-current electron beam is presented. Using the present approach, linear growth rates of the Weibel instability are derived for the cold and finite-temperature beams.

Authors:
; ; ;  [1];  [2];  [2]
  1. Department of Physics and Institute for Fusion Studies, University of Texas at Austin, Austin, Texas 78712 (United States)
  2. (United States)
Publication Date:
OSTI Identifier:
20974942
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 14; Journal Issue: 4; Other Information: DOI: 10.1063/1.2710812; (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; BEAM-PLASMA SYSTEMS; COLLISIONLESS PLASMA; ELECTRON BEAMS; ELECTRON TEMPERATURE; ELECTRONS; ION TEMPERATURE; NONLINEAR PROBLEMS; PLASMA INSTABILITY; PLASMA SIMULATION; RELATIVISTIC PLASMA; RELATIVISTIC RANGE; TWO-DIMENSIONAL CALCULATIONS

Citation Formats

Polomarov, Oleg, Sefkow, Adam B., Kaganovich, Igor, Shvets, Gennady, Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543, and Department of Physics and Institute for Fusion Studies, University of Texas at Austin, Austin, Texas 78712. Computationally efficient description of relativistic electron beam transport in collisionless plasma. United States: N. p., 2007. Web. doi:10.1063/1.2710812.
Polomarov, Oleg, Sefkow, Adam B., Kaganovich, Igor, Shvets, Gennady, Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543, & Department of Physics and Institute for Fusion Studies, University of Texas at Austin, Austin, Texas 78712. Computationally efficient description of relativistic electron beam transport in collisionless plasma. United States. doi:10.1063/1.2710812.
Polomarov, Oleg, Sefkow, Adam B., Kaganovich, Igor, Shvets, Gennady, Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543, and Department of Physics and Institute for Fusion Studies, University of Texas at Austin, Austin, Texas 78712. Sun . "Computationally efficient description of relativistic electron beam transport in collisionless plasma". United States. doi:10.1063/1.2710812.
@article{osti_20974942,
title = {Computationally efficient description of relativistic electron beam transport in collisionless plasma},
author = {Polomarov, Oleg and Sefkow, Adam B. and Kaganovich, Igor and Shvets, Gennady and Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 and Department of Physics and Institute for Fusion Studies, University of Texas at Austin, Austin, Texas 78712},
abstractNote = {A reduced approach to modeling the electromagnetic Weibel instability and relativistic electron beam transport in collisionless background plasma is developed. Beam electrons are modeled by macroparticles and the background plasma is represented by electron fluid. Conservation of generalized vorticity and quasineutrality of the plasma-beam system are used to simplify the governing equations. The method is suitable for modeling the nonlinear stages of collisionless beam-plasma interaction. A computationally efficient code based on this reduced description is developed and benchmarked against a standard particle-in-cell code. The full-scale two-dimensional numerical simulation of the Weibel instability saturation of a low-current electron beam is presented. Using the present approach, linear growth rates of the Weibel instability are derived for the cold and finite-temperature beams.},
doi = {10.1063/1.2710812},
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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