Design considerations and operations for Pegasus-III linear plasma injector test facility

Pegasus-III is dedicated to solenoid-free plasma initiation technologies. For in-vessel helicity injectors, rapid component design and commissioning is critical. The surfaces of new components need to be conditioned prior to full power operation to avoid cathode spot formation, which may damage the injectors. To minimize injector conditioning time on Pegasus-III, a new linear plasma facility is being developed to support local helicity injection technology. This facility will have an on-axis magnetic field comparable to that of Pegasus-III, on order > 0.1 T and capability to study conditioning injector surfaces through removal of oxide layers and surface roughness by gradually increasing applied voltage up to 2 kV at 4 kA. This will provide a test bed for rapid prototyping of injector technology and surface treatments such as nitriding and peening. With injectors capable of high energy (2keV) and high particle flux (~5e21 m-2 s-1) as an electron or ion source, this facility will provide the capability to subject materials to extreme plasma conditions. Future work will leverage the UW nuclear reactor and Ion Beam Laboratory to conduct PMI of irradiated materials.