On the nature of charged particle flow of vacuum arc

Time resolving investigations of charged particles flow from the cathode region of the vacuum arc reveal that the basis of charged particles flow is short-term burst. These bursts can form sequences, groups with a relatively smooth waveform and superbursts. The Fourier analysis showed that ion flow has a brown-like frequency law. This fact can serve as evidence of the fractal nature of the cathode spot. However, the detailed analysis of ionsand accelerated electron signals revealed that the fractal nature of charged particle signal can reflect the fractal nature of plasma turbulences in discharge plasma. Also, the strong correlation between intensive charged particle flow appearance and arc discharge parameter instabilities was revealed. Thus, the plasma instabilities can be considered as the cause of ion and electron flow acceleration in the vacuum arc. (paper)