Perveance of a high-impedance diode with blade explosive emission cathodes

Summary form only given. The electron explosive emission based cathodes with a solid surface have a high emission capability that causes the definite challenge in their application in the accelerators with an impedance of over tens of Ohm. The application of the blade cathodes enables to reduce the number of emission centers, to provide the significant delay of the intensive emission, and thus to provide the effective operation in such accelerators. The findings of the perveance of the high-impedance diode with a blade explosive emission cathode at different diode gap-to-cathode radius ratio have been presented. The blade cathode is made from the coiled copper band. The duration of the applied voltage pulse is 450 ns (at the level of 0.1-0.9) under a peak accelerating voltage of 500 kV. A distinguishing feature of an electron beam generation in the experiments carried out is a rather high duration of the accelerating voltage front, which is over 0.1 μs, and a high output impedance of the accelerator, which is about 220 Ω. On the basis of the experimental data, we suggested an analytical model for variation of the diode perveance allowing for the edge effects on the blade cathode during the generation of an electron beam. The model describes adequately the behavior of the diode perveance under changes of the ratio d_AK/r = 0.7-1.4 and of the cathode material.