Initial Design and Results from an Ion Current Collection Diagnostic for the Triggered Plasma Opening Switch Experiment

Study of the triggered plasma opening switch (TPOS) characteristics is in progress via an ion current collection diagnostic (ICCD), in addition to offline apparatus. This initial ion current collection diagnostic has been designed, fabricated, and tested on the TPOS in order to explore the opening profile of the main switch. The initial ion current collection device utilizes five collectors which are positioned perpendicularly to the main switch stage in order to collect radially traveling ions. It has been shown through analytical prowess that this specific geometry can be treated as a planar case of the Child-Langmuir law with only a 6% deviation from the cylindrical case. Additionally, magnetostatic simulations with self consistent space charge emitting surfaces of the main switch using the Trak code are under way. It is hoped that the simulations will provide evidence in support of both the analytical derivations and experimental data. Finally, an improved design of the ICCD (containing 12 collectors in the axial direction) is presently being implemented.