Vacuum discharge as an effective source of multiply charged ions

The time-of-flight (TOF) spectra measured under high vacuum conditions revealed ion beams of a cathode material (Cu n + ) with a maximum charge of up to +19 generated in the initial stage of a spark discharge development at a storage voltage of up to U 0 =2.5 kV. As the U 0 value increases, the range of the multiply charged states of ions detected by the TOF technique increases, the average ion charge reaching +9.