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arXiv · 1707.05901

Differential formulation of the gyrokinetic Landau operator

Eero Hirvijoki·Alain J. Brizard·David Pfefferlé
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Abstract

Subsequent to the recent rigorous derivation of an energetically consistent gyrokinetic collision operator in the so-called Landau representation, this paper investigates the possibility of finding a differential formulation of the gyrokinetic Landau collision operator. It is observed that, while a differential formulation is possible in the gyrokinetic phase space, reduction of the resulting system of partial differential equations to five dimensions via gyroaveraging poses a challenge. Based on the present work, it is likely that the gyrocentre analogues of the Rosenbluth-MacDonald-Judd potential functions must be kept gyroangle dependent.

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Eero Hirvijoki, Alain J. Brizard, David Pfefferlé. 2017-07-19. Differential formulation of the gyrokinetic Landau operator. https://doi.org/10.1017/s0022377816001203

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