Abstract
The solution of the Grad–Shafranov (GS) equation, which is at the basis of Tokamak plasma MHD equilibrium computation, in the fixed boundary formulation first requires the description of the plasma boundary in terms of a few physical quantities. Limiter plasmas are characterized by a boundary that is a closed magnetic surface tangent to a material surface for which there is a simple parametrization in terms of those quantities. Divertor plasmas are, by contrast, characterized by a boundary that is not a closed flux surface nor tangent to any material surface, but contains saddle point(s) at which the boundary has cusp(s) of 90◦. For such a boundary the limiter plasma parametrization is no longer valid. We investigate whether there is an analogous simple parametrization of divertor plasma boundaries.
Content
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