Accelerating tube of «Gamma-4» pulsed power facility module

The accelerating tube of "Gamma-4" pulsed power facility module is presented. The facility is now being built at RFNC-VNIIEF. The accelerating tube is the part of pulse transmission system of the module. This system provides high-voltage electric pulse delivering from forming system output to the diode load. The specific feature of a tube design is using of dielectric lens for better grading of electric field stress distribution over vacuum insulator surface. Using the lens made possible to lower electric field stress by 30% and reduced insulator flashover probability correspondingly. The dimensions of the tube were determined by average electric field stress values that not exceed 55 kV/cm. The inductance of the tube is 87 nH. 230 shots were done with accelerating tube with the voltage on insulator up to 2.7 MV. No electric breakdowns of insulator have been observed in these shots.