DEVELOPMENT OF TIMING AND CONTROL SYSTEMS FOR FAST BEAM SWITCH AT KEK 8 GEV LINAC

The 8-GeV Linac at KEK provides electrons and positrons to Photon Factory (PF) and B-Factory (KEKB). Simultaneous top-up injections have been considered for both PF and KEKB rings in order to improve the injec- tion efficiency and the experimental stability. Therefore, fast beam-switching mechanisms are being implemented, upgrading the timing and control systems. While the old timing system provides precise timing signals for 150 de- vices, many of the signals are now dynamically switched using an event system. A new scheme has been developed and tested to enable double-fold synchronization between rf signals. Fast controls of low-level rf, beam instrumen- tation, kickers, a gun, and beam operation parameters are also upgraded for fast and precise tuning of those param- eters. The system has been developed since 2006, and is being deployed under the beam operation in 2008.