The design of HEPS global timing system

Purpose The high energy photon source(HEPS)is a 4th generation synchrotron light source under construction by the institute of high energy physics.The accelerator complex consists of a 500-MeV Linac,a full-energy synchrotron booster,a 6-GeV synchrotron storage ring(SR),and three e-beam transport lines for injection and extraction among accelerators.A global timing system(GTS)covers the timing needs for all accelerator,beamline,and experiment systems.The GTS is designed to coordinate the injection processes and various measurements and protections.Most systems require that the RMS jitter of the GTS signal is less than 30 ps,while the trigger jitters for the electron gun and SR injection and extraction kickers are less than 10 ps.Method The HEPS GTS is an event-based timing system based on MicroTCA.4 hardware architecture.The MicroTCA.4300 series products from the micro-research Finland Oy are implemented in the HEPS GTS system.Results and conclusions The RMS jitter,integrated from 1 Hz to 10 MHz,of the 166.6 MHz event clock is 5.489 ps.The RMS jitter of TTL outputs is less than 30 ps.This paper reports the design of the HEPS GTS,which satisfies all of the HEPS physics requirements for timing with preliminary test results shown.