Mechanism for initiation of pseudospark discharge by ions ejected from the anode side

This paper presents a discussion of the discharge formation mechanism for a pseudospark switch at the conditions when the discharge is initiated by an ion beam ejected from the anode side. Experimental data show that the switch is triggered only in case when the cathode has a cavity. Then, the major factor effecting in the discharge initiation is the space charge of positive ions, which forms in the cavity. Due to this charge, the electric field is distorted in such a manner that a potential trap for secondary cathode electrons appears and the oscillatory motion of electrons provides for intense generation of plasma inside the cavity. The hollow cathode plasma serves as a source of an electron beam for the main gap, so that the switch is finally triggered under the effect of this beam.