Equilibrium and stability of current-carrying discharges in the non-axisymmetric CTH experiment

Detailed knowledge of the experimental plasma equilibrium is becoming as important for stellarators as it is for tokamaks, but reconstruction of magnetic flux surfaces from magnetic measurements is more difficult in the three-dimensional geometry of stellarators than in axisymmetric configurations. We report the first reconstructions of experimental stellarator equilibria with the V3FIT [1] code. We also introduce the signal effectiveness, and describe initial studies of density-driven disruption in current-carrying stellarator plasmas. At low vacuum transform, disruptions can be triggered at a plasma density comparable to the Greenwald limit, but disruption signatures disappear as the vacuum rotational transform is raised above 0.1.