PLASMA GRID CATHODE BASED ON ARC DISCHARGE IN A MAGNETIC FIELD FOR GENERATION ELECTRON BEAM OF VARIABLE DIAMETER
Vladimir Devyatkov, N.N. Koval
IHCE SB RAS, Tomsk, Russian Federation
May be, a discharge begin between cathode grid and redistr. electrode (RE), supported by ion flow from the transporting area (TA) and electron flow from RE due to ion-electron secondary emission? For small B1 plasma in TA may diffuse to axis easy.
The voltage between the R-E electrode and the grid occurs only when the discharge current flows from the cathode to the R-E. Although the voltage across Ra will provide the addition of secondary electrons from the R-E electrode to the beam, the contribution to the overall picture is probably not so great at the nominal operating pressure.
May be, of course... But all events occur simultaneously and contribution of this discharge may be not small.