Confinement of Non-neutral Plasmas in Stellarator Magnetic Surfaces

The Columbia Non-neutral Torus (CNT) is the first experiment designed to create and study small Debye length non-neutral plasmas confined by magnetic surfaces. This thesis describes experimental confinement studies of non-neutral plasmas on magnetic surfaces in CNT. Open orbits exist in CNT resulting in electron loss rates that are much faster than initially predicted. For this reason a conforming boundary was designed and installed to address what is believed to be the primary cause of open orbits: the existence of a sizable mismatch between the electrostatic potential surfaces and the magnetic surfaces. After installation a record confinement time of 337 ms was measured, more than an order of magnitude improvement over the previous 20 ms record. This improvement was a combination of the predicted improvement in orbit quality, a reduced Debye length that resulted in decreased transport due to the perturbing insulated rods, and improved operating parameters not indicative of any new physics. The perturbation caused by the insulated rods that hold emitters on axis in CNT is a source of electron transport and would provide a loss mechanism for positrons in future positron-electron pl