Monitoring and influence analysis of flashes on insulator surface of high current diode

A current diagnostic system included a B-dot array and a Rogowski coil was designed for the Flash Ⅱ accelerator diode. Flashes on the insulator surface were monitored and their impact on the output of the diode was discussed based on the differences between the current probes. The waveforms of the B-dot near the position of flashes were distorted, and the waveforms of the other B-dots and the Rogowski coil accorded with those without flash. Compared with no flash situation, the electron beam intensity and energy of the diode, derived with measurements of the B-dot far away from the flash, did not reduce obviously. Flashes on the insulator surface were local discharges and had little impact on the output of high current diodes for the accelerators like Flash-Ⅱ accelerator．