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arXiv · 2607.28305

Variational Formulation of a Hybrid Kinetic and Gyrokinetic Model for Astrophysical and Laboratory Plasmas

F. N. deOliveira-Lopes·S. C. Thatikonda·D. Told·A. Mustonen·K. Pommois·K. Hagiwara·F. Jenko·R. Grauer
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Abstract

We present a Lagrangian model that encapsulates fully kinetic ions and gyrokinetic electrons for solar wind electromagnetic turbulence. Using a consistent method, where both electrons and protons are treated with the same mathematical formalism, we derive and implement a model in which high-frequency waves and kinetic electron effects are described in a computationally cost-efficient way. Higher-order Lie-transform perturbation methods applied to Hamiltonian formulation of guiding center motion are used to describe the dynamics of particles and fields. We use a variational approach to derive field equations for closure of the system.

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F. N. deOliveira-Lopes, S. C. Thatikonda, D. Told, A. Mustonen, K. Pommois, K. Hagiwara, F. Jenko, R. Grauer. 2026-07-30. Variational Formulation of a Hybrid Kinetic and Gyrokinetic Model for Astrophysical and Laboratory Plasmas. https://arxiv.org/abs/2607.28305

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