DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: On the validity of the guiding-center approximation in the presence of strong magnetic gradients

Abstract

The motion of a charged particle in a nonuniform straight magnetic field with a constant magnetic-field gradient is solved exactly in terms of elliptic functions. The connection between this problem and the guiding-center approximation is discussed. Here, it is shown that, for this problem, the predictions of higher-order guiding-center theory agree very well with the orbit-averaged particle motion and hold well beyond the standard guiding-center limit $$\epsilon$$ $$\equiv$$ p/L << 1, where p is the gyromotion length scale and L is the magnetic-field gradient length scale.

Authors:
ORCiD logo [1]
  1. Saint Michael's College, Colchester, VT (United States). Dept. of Physics
Publication Date:
Research Org.:
Saint Michael's College, Colchester, VT (United States). Dept. of Physics
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1465758
Alternate Identifier(s):
OSTI ID: 1361830
Grant/Contract Number:  
SC0014032
Resource Type:
Accepted Manuscript
Journal Name:
Physics of Plasmas
Additional Journal Information:
Journal Volume: 24; Journal Issue: 4; Journal ID: ISSN 1070-664X
Publisher:
American Institute of Physics (AIP)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY

Citation Formats

Brizard, Alain J. On the validity of the guiding-center approximation in the presence of strong magnetic gradients. United States: N. p., 2017. Web. doi:10.1063/1.4981217.
Brizard, Alain J. On the validity of the guiding-center approximation in the presence of strong magnetic gradients. United States. https://doi.org/10.1063/1.4981217
Brizard, Alain J. Tue . "On the validity of the guiding-center approximation in the presence of strong magnetic gradients". United States. https://doi.org/10.1063/1.4981217. https://www.osti.gov/servlets/purl/1465758.
@article{osti_1465758,
title = {On the validity of the guiding-center approximation in the presence of strong magnetic gradients},
author = {Brizard, Alain J.},
abstractNote = {The motion of a charged particle in a nonuniform straight magnetic field with a constant magnetic-field gradient is solved exactly in terms of elliptic functions. The connection between this problem and the guiding-center approximation is discussed. Here, it is shown that, for this problem, the predictions of higher-order guiding-center theory agree very well with the orbit-averaged particle motion and hold well beyond the standard guiding-center limit $\epsilon$ $\equiv$ p/L << 1, where p is the gyromotion length scale and L is the magnetic-field gradient length scale.},
doi = {10.1063/1.4981217},
journal = {Physics of Plasmas},
number = 4,
volume = 24,
place = {United States},
year = {Tue Apr 18 00:00:00 EDT 2017},
month = {Tue Apr 18 00:00:00 EDT 2017}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 9 works
Citation information provided by
Web of Science

Save / Share:

Works referenced in this record:

Guiding-center Hamiltonian for large gyroexcursion particles in mirror configurations
journal, January 1980


Drift velocity of charged particles in magnetic fields and its relation to the direction of the source current
journal, October 2016


Hamiltonian theory of guiding-center motion
journal, May 2009


Linear gyrokinetic simulations of microinstabilities within the pedestal region of H-mode NSTX discharges in a highly shaped geometry
journal, June 2016

  • Coury, M.; Guttenfelder, W.; Mikkelsen, D. R.
  • Physics of Plasmas, Vol. 23, Issue 6
  • DOI: 10.1063/1.4954911

Motion of charged particles near magnetic-field discontinuities
journal, June 2001


Canonical transformation for trapped/passing guiding-center orbits in axisymmetric tokamak geometry
journal, May 2014

  • Brizard, Alain J.; Duthoit, François-Xavier
  • Physics of Plasmas, Vol. 21, Issue 5
  • DOI: 10.1063/1.4879811

Charged particle trajectories in simple nonuniform magnetic fields
journal, July 1991

  • Repko, Jane M.; Repko, Wayne W.; Saaf, Allan
  • American Journal of Physics, Vol. 59, Issue 7
  • DOI: 10.1119/1.16788

Gyrokinetic equations for strong-gradient regions
journal, February 2012


Drift of a Charged Particle in a Static Magnetic Field Having a Power Law Dependence
journal, January 1975

  • Headland, M.; Seymour, Pw
  • Australian Journal of Physics, Vol. 28, Issue 3
  • DOI: 10.1071/PH750289

Guiding-Center Hamiltonian for Arbitrary Gyration
journal, October 1979


Compact formulas for guiding-center orbits in axisymmetric tokamak geometry
journal, February 2011


Lagrangian and Hamiltonian constraints for guiding-center Hamiltonian theories
journal, November 2015

  • Tronko, Natalia; Brizard, Alain J.
  • Physics of Plasmas, Vol. 22, Issue 11
  • DOI: 10.1063/1.4935925

Compact formulas for bounce/transit averaging in axisymmetric tokamak geometry
journal, December 2014

  • Duthoit, F. -X.; Brizard, A. J.; Hahm, T. S.
  • Physics of Plasmas, Vol. 21, Issue 12
  • DOI: 10.1063/1.4903885

Foundations of nonlinear gyrokinetic theory
journal, April 2007


Works referencing / citing this record:

Global simulation of ion temperature gradient instabilities in a field-reversed configuration
journal, April 2019

  • Bao, J.; Lau, C. K.; Lin, Z.
  • Physics of Plasmas, Vol. 26, Issue 4
  • DOI: 10.1063/1.5087079