One-dimensional simulation studies of breakdown and electron beam generation processes for a hollow cathode pseudospark discharge

We have developed a 1-D model to study the importance of some of the basic physical processes involved in a low pressure discharge. Our results show that during the early stage of the discharge, the emitted electron current comes mainly from the secondary emission off the cathode. Meanwhile, a quasi-neutral plasma column is being formed in the gap via ionization. The growing plasma oscillations are excited by the fast electrons from the cathode as they pass through the plasma due to the two-stream instability. The oscillation heats the background electrons to energies above the ionization threshold and ultimately leads to a rapid increase in both the plasma density and electron current at the anode. To our knowledge previous pseudospark models have not included ionization of the ambient gas due to the heated background charged particles within the dense quasi-neutral plasma region. Under this 1-D model, the discharge approximately satisfies a Paschen's Law in the low pressure regime.<
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