Generation of multiply charged ions from a cathode jet of a low-energy vacuum spark

Ion parameters in a cathode plasma jet of a vacuum spark with a discharge energy of a few joules were measured. The studies were performed by a time-of-flight method with the help of an energy analyser. It was found that the discharge plasma generated a short-run beam of multiply charged ions of the cathode material at the initial stage of the discharge firing. The ions had charge states from Z = +1 up to Z = +18. When the initial capacitor voltage was varied within the ranges of 0.3-2.5 kV, the mean ion charge increased from +4.3 to +9.0.