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arXiv · 1907.13439

Pad\'e-based arbitrary wavelength polarization closures for full-F gyro-kinetic and -fluid models

Markus Held·Matthias Wiesenberger·Alexander Kendl
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Abstract

We propose a solution to the long-standing short wavelength polarization closure shortfall of full-F gyro-fluid models. This is achieved by first finding an appropriate quadratic form of the gyro-fluid moment over the polarization part of the gyro-center Hamiltonian. Secondly, we deduce Pad\'e-based approximations to the latter expression that produce a polarization charge density with the desired order of accuracy and retain linear polarization effects for arbitrary wavelengths. The proposed closures feature proper energy conservation and the anticipated Oberbeck-Boussinesq and long wavelength limits.

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Markus Held, Matthias Wiesenberger, Alexander Kendl. 2019-07-31. Pad\'e-based arbitrary wavelength polarization closures for full-F gyro-kinetic and -fluid models. https://doi.org/10.1088/1741-4326%2Fab7a68

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