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 plasmabeam system are used to simplify the governing equations. The method is suitable for modeling the nonlinear stages of collisionless beamplasma interaction. A computationally efficient code based on this reduced description is developed and benchmarked against a standard particleincell code. The fullscale twodimensional numerical simulation of the Weibel instability saturation of a lowcurrent electron beam is presented. Using the present approach, linear growth rates of the Weibel instability are derived for the cold and finitetemperature beams.
 Authors:
 Department of Physics and Institute for Fusion Studies, University of Texas at Austin, Austin, Texas 78712 (United States)
 (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; BEAMPLASMA SYSTEMS; COLLISIONLESS PLASMA; ELECTRON BEAMS; ELECTRON TEMPERATURE; ELECTRONS; ION TEMPERATURE; NONLINEAR PROBLEMS; PLASMA INSTABILITY; PLASMA SIMULATION; RELATIVISTIC PLASMA; RELATIVISTIC RANGE; TWODIMENSIONAL 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 plasmabeam system are used to simplify the governing equations. The method is suitable for modeling the nonlinear stages of collisionless beamplasma interaction. A computationally efficient code based on this reduced description is developed and benchmarked against a standard particleincell code. The fullscale twodimensional numerical simulation of the Weibel instability saturation of a lowcurrent electron beam is presented. Using the present approach, linear growth rates of the Weibel instability are derived for the cold and finitetemperature 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}
}

Nonlinear stabilization of the collisionless radial defocusing of a relativistic electron beam in a plasma
The defocusing effect of the Cerenkov and cylcotron modes on a relativistic electron beam in a plasma is studied for a beam directed along the external magnetic field. The role of nonlinear effects during the collective scattering of resonant electrons by plasma waves is determined. Possible mechanisms for the nonlinear suppression of the instability are offered. Nonlinear saturation of the Cerenkov mode occurs even in a weak magnetic field because of a decrease in the growth rate with increasing amplitude of the waves in the beam. The cyclotron (anomalous Doppler) mode is stabilized by the nonlinear dispersion in the plasma,more » 
Kinetic description of coupled transverse oscillations in an intense relativistic electron beamplasma system
The stability properties of an intense relativistic electron beam propagating through a collisionless background plasma are investigated within the framework of the VlasovMaxwell equations. It is assumed that ..nu../sub j//..gamma../sub j/<<1, where j=b,e,i denote beam electrons, plasma electrons, and plasma ions, respectively, and ..nu../sub j/ and ..gamma../sub j/m/sub j/c/sup 2/ are Budker's parameter and the characteristic energy, respectively, of the plasma component j. The analysis is carried out for the class of rigidrotor equilibrium distribution functions in which all particles of plasma component j have the same value of energy in a frame rotating with angular velocity ..omega../sub j/ andmore » 
Plasma wakefield effects on highcurrent relativistic electron beam transport in the ionfocused regime
Modulation of the beam current has recently been observed during ionfocused regime (IFR) transport of a highpower relativistic electron beam propagating through a lowdensity background plasma. Injecting a highcurrent, highenergy electron beam into an IFR channel immersed in a background plasma induces plasma oscillations. These background plasma oscillations, induced by the risetime portion of the beam ejecting plasma electrons from the vicinity of the beam into the background plasma, give rise to a modulated axial electric field. This field travels with the beam leading to beam energy and current oscillations. In the experiment, a 1.7 MeV, 1 kA, risetimesharpened electronmore »