Pulse-to-Pulse Modulation of Injector Linac with Event Timing System

The Pulse-to-Pulse Modulation of Injector Linac at KEK is developed for efficient injections. It automatically switches the beam mode with the real-time process. We integrated this system in 2009 to simultaneously perform the top-up filling into more than one rings with only one injector. The system is based on the Event Timing System. Recently, we upgraded the configuration of Event Timing System to satisfy the complicated requirements of SuperKEKB and developed the test procedure to understand stability of real-time process. The failure of real-time process at Main Trigger Station is intentionally caused when we shorten the allowed computing time as the stress test. The reasonable dependence between the failure rate and the allowed computing time is determined. It indicates we can evaluate the failure rate in case of normal operation at Main Trigger Station.