Electric Field Mechanism of Thin Plasma Jet Formation in an Open Atmospheric Discharge

Experimental and theoretical investigations of a new form of pulsed periodic discharge burning in the form of a thin plasma jet – apokamp – have been carried out. It is shown that for sustainable apokamp formation, the presence of a weak external electric field is required which is enhanced near the head of a growing streamer at the expense of good conductivity of the plasma trace. It is experimentally demonstrated that the apokamp formation is initiated by external electric field strength of ~1 kV/cm.