Rigidity of MHD equilibria to smooth incompressible ideal motion near resonant surfaces

Research output: Contribution to journalArticlepeer-review

1 Citation (Scopus)
28 Downloads (Pure)

Abstract

In ideal MHD, the magnetic flux is advected by the plasma motion, freezing flux-surfaces into the flow. An MHD equilibrium is reached when the flow relaxes and force balance is achieved. We ask what classes of MHD equilibria can be accessed from a given initial state via smooth incompressible ideal motion. It is found that certain boundary displacements are formally not supported. This follows from yet another investigation of the Hahm--Kulsrud--Taylor (HKT) problem, which highlights the resonant behaviour near a rational layer formed by a set of degenerate critical points in the flux-function. When trying to retain the mirror symmetry of the flux-function with respect to the resonant layer, the vector field that generates the volume-preserving diffeomorphism vanishes at the identity to all order in the time-like path parameter.
Original languageEnglish
Number of pages9
JournalPlasma Physics and Controlled Fusion
Volume62
Issue number7
DOIs
Publication statusPublished - Jul 2020

Fingerprint

Dive into the research topics of 'Rigidity of MHD equilibria to smooth incompressible ideal motion near resonant surfaces'. Together they form a unique fingerprint.

Cite this