Investigation of a vacuum spark discharge with preliminary formed anode plasma cloud

The measurement of parameters of ion flow emanating from anode plasma has been performed. Anode plasma was accelerated by explosive emission electron flow. For preliminary formation of anode plasma the flashover discharge on an internal surface of a dielectric ring has been used. The voltage pulse with 100ns duration and 30kV amplitude was applied to the cathode. Time delay between anode plasma formation and application of voltage pulse on the cathode was 75ns. Charged particle flow parameters was analysed with Thomson spectrometer. It was found that the flow of explosion electrons, interacting with plasma cloud, dissipates and decreases. The energies of ions, accelerated from plasma cloud have wide distribution, and do not exceed the amplitude of voltage pulse.