A method for obtaining threedimensional computation equilibrium of nonneutral plasmas using WARP
Abstract
Computer simulation studies of the stability and transport properties of trapped nonneutral plasmas require the numerical realization of a threedimensional plasma distribution. This paper presents a new numerical method for obtaining, without an explicit model for physical collisions in the code, a low noise threedimensional computational equilibrium distribution. This requires both the loading of particles into an idealized distribution and the relaxation from that distribution toward an approximate numerical equilibrium. The equilibrium can then be modified through a slow change of system parameters, to generate other equilibria. In the present work we apply this method to a UC Berkeley experiment on electron confinement in magnetic geometries appropriate for the ALPHA antihydrogen experiment, using the threedimensional ParticleInCell code WARP. WARP's guiding center mover and its option to switch between different solvers during a simulation are highly valuable because they speed up the simulations; they enable the practical use of the new technique for generating numerical equilibrium states of trapped nonneutral plasmas.
 Authors:
 Publication Date:
 Research Org.:
 Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
 Sponsoring Org.:
 Accelerator& Fusion Research Division
 OSTI Identifier:
 928303
 Report Number(s):
 LBNL256E
Journal ID: ISSN 00219991; JCTPAH; TRN: US0804322
 DOE Contract Number:
 DEAC0205CH11231
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Computational Physics
 Country of Publication:
 United States
 Language:
 English
 Subject:
 70; COMPUTERIZED SIMULATION; CONFINEMENT; DISTRIBUTION; ELECTRONS; PLASMA; RELAXATION; SIMULATION; STABILITY; TRANSPORT; VELOCITY; WARP NonNeutral Plasmas
Citation Formats
Wurtele, J., Wurtele, J., Friedman, A., Grote, D.P., Vay, JL., and Gomberoff, K. A method for obtaining threedimensional computation equilibrium of nonneutral plasmas using WARP. United States: N. p., 2006.
Web.
Wurtele, J., Wurtele, J., Friedman, A., Grote, D.P., Vay, JL., & Gomberoff, K. A method for obtaining threedimensional computation equilibrium of nonneutral plasmas using WARP. United States.
Wurtele, J., Wurtele, J., Friedman, A., Grote, D.P., Vay, JL., and Gomberoff, K. Sat .
"A method for obtaining threedimensional computation equilibrium of nonneutral plasmas using WARP". United States.
doi:. https://www.osti.gov/servlets/purl/928303.
@article{osti_928303,
title = {A method for obtaining threedimensional computation equilibrium of nonneutral plasmas using WARP},
author = {Wurtele, J. and Wurtele, J. and Friedman, A. and Grote, D.P. and Vay, JL. and Gomberoff, K.},
abstractNote = {Computer simulation studies of the stability and transport properties of trapped nonneutral plasmas require the numerical realization of a threedimensional plasma distribution. This paper presents a new numerical method for obtaining, without an explicit model for physical collisions in the code, a low noise threedimensional computational equilibrium distribution. This requires both the loading of particles into an idealized distribution and the relaxation from that distribution toward an approximate numerical equilibrium. The equilibrium can then be modified through a slow change of system parameters, to generate other equilibria. In the present work we apply this method to a UC Berkeley experiment on electron confinement in magnetic geometries appropriate for the ALPHA antihydrogen experiment, using the threedimensional ParticleInCell code WARP. WARP's guiding center mover and its option to switch between different solvers during a simulation are highly valuable because they speed up the simulations; they enable the practical use of the new technique for generating numerical equilibrium states of trapped nonneutral plasmas.},
doi = {},
journal = {Journal of Computational Physics},
number = ,
volume = ,
place = {United States},
year = {Sat Mar 25 00:00:00 EST 2006},
month = {Sat Mar 25 00:00:00 EST 2006}
}

Computer simulation studies of the stability and transport properties of trapped nonneutral plasmas require the numerical realization of a threedimensional plasma distribution. This paper presents a new numerical method for obtaining, without an explicit model for physical collisions in the code, a low noise threedimensional computational equilibrium distribution. This requires both the loading of particles into an idealized distribution and the relaxation from that distribution toward an approximate numerical equilibrium. The equilibrium can then be modified through a slow change of system parameters, to generate other equilibria. In the present, work we apply this method to a UC Berkeley experimentmore »

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