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arXiv · 2410.02175

Non-perturbative guiding center model for magnetized plasmas

J. W. Burby·I. A. Maldonado·M. Ruth·D. A. Messenger
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Abstract

Perturbative guiding center theory adequately describes the slow drift motion of charged particles in the strongly-magnetized regime characteristic of thermal particle populations in various magnetic fusion devices. However, it breaks down for particles with large enough energy. We report on a data-driven method for learning a non-perturbative guiding center model from full-orbit particle simulation data. We show the data-driven model significantly outperforms traditional asymptotic theory in magnetization regimes appropriate for fusion-born $\alpha$-particles in stellarators, thus opening the door to non-perturbative guiding center calculations.

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J. W. Burby, I. A. Maldonado, M. Ruth, D. A. Messenger. 2024-10-03. Non-perturbative guiding center model for magnetized plasmas. https://arxiv.org/abs/2410.02175

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