English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

We propose a novel derivation of the gyrokinetic field-particle Lagrangianfor non-collisional ion-electron plasmas in a magnetic background with strongvariations (maximal ordering). Our approach follows the two-step reductionprocess, where the guiding-center coordinate transformation is followed by thegyrocenter coordinate transformation in the single-particle phase space. Forthe first time both steps are addressed within a unique methodology, based onnear-identity coordinate transformations constructed as polynomial transforms.These are well-defined transformations composed of a finite number of termsthat are linear and algebraic with respect to the generating functions. Thederivation is carried out in a fully non-dimensional framework, based onparameters governing the magnetic fusion experiments ASDEX Upgrade and ITER.Our method leads to a gyrokinetic Vlasov-Maxwell model for ions and electrons,derived without the use of Lie perturbation methods. It is found that, based onthe employed ordering, curvature terms such as the gyro-gauge term and theBa\~nos drift appear at first order in the ion Hamiltonian, whereas ionpolarization terms appear only at second order. By contrast, curvature termsare absent from the first-order electron Hamiltonian, where instead magneticflutter plays a role.

Gyrokinetic theory with polynomial transforms: a model for ions and electrons in maximal ordering