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arXiv · 1905.12316

Hamiltonian for guiding center motion: symplectic structure approach

Anatoly Neishtadt·Anton Artemyev
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Abstract

The guiding center approximation represents a very powerful tool for analyzing and modeling a charged particle motion in strong magnetic fields. This approximation is based on conservation of the adiabatic invariant, magnetic moment. Hamiltonian equations for the guiding centre motion are traditionally intoduced using a non-canonical symplectic structure. Such approach requires application of non-canonical Hamiltonian perturbation theory for calculations of the magnetic moment corrections. In this study we present an alternative approach with canonical Hamiltonian equations for guiding centre motion in time-dependent electromagnetic fields. We show that the derived Hamiltonian decouples three types of motion (gyrorotation, field-aligned motion, and across-field drifts), and each type is described by a pair of conjugate variables. This form of Hamiltonian and symplectic structure allows simple introduction of adiabatic invariants and can be useful for analysis of various plasma systems.

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Anatoly Neishtadt, Anton Artemyev. 2019-05-29. Hamiltonian for guiding center motion: symplectic structure approach. https://arxiv.org/abs/1905.12316

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