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arXiv · 2111.05353

On the validity of the guiding-center approximation in a magnetic dipole field

Alain J Brizard·Danielle G Markowski
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Abstract

The problem of the charged-particle motion in an axisymmetric magnetic-dipole geometry is used to assess the validity of Hamiltonian guiding-center theory, which includes higher-order corrections associated with guiding-center polarization induced by magnetic-field nonuniformity. 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 guiding-center polarization effects are taken into account.

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Alain J Brizard, Danielle G Markowski. 2021-11-09. On the validity of the guiding-center approximation in a magnetic dipole field. https://doi.org/10.1063/5.0078786

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