RESONANT LASER DIAGNOSTICS OF A PLANAR PLASMA OPENING SWITCH

The plasma opening switch (POS) is an integral part of inductive store pulsed power systems. Using flashboards coated with BaO and a dye las er tuned to the 493.4 nm ground state transition of the singly-ionized barium ion, resonant laser diagnostics have been employed to image th e switch plasma and provide a measurement of the plasma density during conduction and opening. Gaps open during the conduction phase with th eir position in the inter-electrode region depending upon the initial fill plasma, There is little axial motion of the plasma, contrary to t he predictions of analytical hydro model calculations performed using the measured switch parameters, This discrepancy may be due to a finit e lifetime for ions in the switch that is less than the conduction tim e resulting in a larger effective mass, From a functional point of vie w modified bipolar model calculations best fit the data.