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Title: Faithful guiding-center orbits in an axisymmetric magnetic field
The problem of the charged-particle motion in an axisymmetric magnetic geometry is used to assess the validity of higher-order Hamiltonian guiding-center theory, which includes higher-order corrections associated with gyrogauge invariance as well as guiding-center polarization induced by magnetic-field non-uniformity. Two axisymmetric magnetic geometries are considered: a magnetic mirror geometry and a simple tokamak geometry. When a magnetically confined charged-particle orbit is regular (i.e., its guiding-center magnetic moment is adiabatically invariant), the guiding-center approximation, which conserves both energy and azimuthal canonical angular momentum, is shown to be faithful to the particle orbit when higher-order corrections are taken into account.  more » « less
Award ID(s):
2206302
PAR ID:
10498420
Author(s) / Creator(s):
;
Publisher / Repository:
American Institute of Physics
Date Published:
Journal Name:
Physics of Plasmas
Volume:
30
Issue:
4
ISSN:
1070-664X
Page Range / eLocation ID:
042115
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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