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arXiv · 1304.6273

Plasmoid solutions of the Hahm--Kulsrud--Taylor equilibrium model

R. L. Dewar·A. Bhattacharjee·R. M. Kulsrud·A. M. Wright
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Abstract

The Hahm--Kulsrud (HK) [T. S. Hahm and R. M. Kulsrud, Phys. Fluids {\bf 28}, 2412 (1985)] solutions for a magnetically sheared plasma slab driven by a resonant periodic boundary perturbation illustrate fully shielded (current sheet) and fully reconnected (magnetic island) responses. On the global scale, reconnection involves solving a magnetohydrodynamic (MHD) equilibrium problem. In systems with a continuous symmetry such MHD equilibria are typically found by solving the Grad--Shafranov equation, and in slab geometry the elliptic operator in this equation is the 2-D Laplacian. Thus, assuming appropriate pressure and poloidal current profiles, a conformal mapping method can be used to transform one solution into another with different boundary conditions, giving a continuous sequence of solutions in the form of partially reconnected magnetic islands (plasmoids) separated by Syrovatsky current sheets. The two HK solutions appear as special cases.

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R. L. Dewar, A. Bhattacharjee, R. M. Kulsrud, A. M. Wright. 2013-04-23. Plasmoid solutions of the Hahm--Kulsrud--Taylor equilibrium model. https://doi.org/10.1063/1.4817276

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