Radial transport reduction in tandem mirrors using end-wall boundary conditions

Results from the Tandem Mirror Experiment‐Upgrade (TMX‐U) demonstrate that radial transport in the plasma volume can be affected by the boundary conditions at the end wall. Measurements in which end‐wall plates, mapping to the plasma core, are switched from floating to grounded during plugging operation demonstrate that this floating increases the build‐up rate of the central cell plasma (by increasing the radial confinement time), steepens the core density profile, and affects the plasma throughout the entire cross section.