Figure 2
From: Finite element methods on composite meshes for tuning plasma equilibria in tokamaks
Sketch for characteristic plasma shapes. Contour lines (black) of the poloidal flux and plasma domain (red): The plasma boundary either (left) touches the limiter (gray) or the plasma is enclosed by a flux contour line (middle and right) that passes through a saddle point. This can be a non-degenerated (middle) in the X-point configuration or degenerated (right) saddle point in the snowflake configuration