Investigation of a plasma flow of a short vacuum spark

The vacuum spark was explored. The pulse of a voltage was put to a vacuum gap by duration 4 ns and amplitude 150kV. At the analysis of plasma flow ions of a material emanating from cathode area with energies up to 150keV are found out. Copper and graphite cathodes were used. In case of the graphite cathode the one-charging ions of carbon with energy bell-shaped distribution were observed only. In case of the copper cathode charging numbers up to 3 are fixed, energy distribution has some maximums. The most probable energies of ions depend on distance the anode-cathode