Available Beta-Value for Tokamak, Screw-Pinch, Spheromak, and Reversed-Field-Pinch in Partially Relaxed States

Numerical results for various types of equilibria in the partially relaxed, minimum-energy states are presented. It is shown that there exists a maximum point of available beta-value in the Screw-pinch type with relatively low current density without the pitch minimum. The available beta-value for the reversed-field-pinch becomes larger in the partially relaxed states dominated by the helical tearing modes with higher toroidal mode numbers.