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Title: Flexibility and rigidity of free boundary MHD equilibria
Abstract We study stationary free boundary configurations of an ideal incompressible magnetohydrodynamic fluid possessing nested flux surfaces. In 2D simply connected domains, we prove that if the magnetic field and velocity field are never commensurate, the only possible domain for any such equilibria is a disk, and the velocity and magnetic field are circular. We give examples of non-symmetric equilibria occupying a domain of any shape by imposing an external magnetic field generated by a singular current sheet charge distribution (external coils). Some results carry over to 3D axisymmetric solutions. These results highlight the importance of external magnetic fields for the existence of asymmetric equilibria.  more » « less
Award ID(s):
2106233
PAR ID:
10373904
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Nonlinearity
Volume:
35
Issue:
5
ISSN:
0951-7715
Page Range / eLocation ID:
2363 to 2384
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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