High Pressure NEQ Plasma Formation by Non-Self-Sustained Repetitively Pulsed Discharges

We describe generation of large volume ($\sim $ 1-2 cm dimension) stable, high pressure non-equilibrium plasmas, utilizing non-self sustained repetitive high voltage pulsing. Ionization is created by means of $\sim $ 10 KV -- 10 nsec duration pulses, repeated at 100 kHz repetition rate. In between the high voltage pulses, the plasma is sustained by application of a relatively low DC or RF field, in which the reduced electric field, E/n, is selected to optimize energy loading into desired molecular degrees of freedom. Detailed measurements of i-V characteristics, plasma lifetime, and heavy species temperature will be presented, along with recent results documenting creation of large ($\sim $5{\%} or more) fractional excitation of O$_{2}$ into the metastable ``single delta'' electronic state, which is the upper lasing level for the oxygen -- iodine laser. Demonstration of turbulent supersonic boundary layer control using Lorentz forces will also be presented.