Timing system of the ATF

A timing system was constructed for Accelerator Test Facility(ATF) for future linear collider R&D at KEK. The operation of the ATF has several features, for example, multi-bunch acceleration, delta-f energy compensation, multi-train storage, etc.. The timing system provides synchronized reference signals and trigger signals for each hardware. To keep stable phase relationships at each component, the reference signals of acceleration frequencies are transferred directly by using phase stabilized optical transfer lines. The beam timing is adjusted with the synchronized delay modules which used ECL preset counter circuits. A bucket selector circuit and a bucket matching circuit are used for manipulation of the beams in the damping ring. CAMAC interfaces and Vsystem for programming were used for control. The hardware performance and the software environment are described.