FERMI@Elettra Optical Timing System


Mario Ferianis
Elettra Sincrotrone Trieste


FERMI@Elettra is a Free Electron Laser User facility in operation in Trieste Italy since aug 2009. In this paper, we present at first the free electron laser layout and the rationale for adopting a femtosecond class optical timing system for the generation and the distribution of the phase reference signal. Then, the optical timing system at FERMI@Elettra is presented, which distributes at 25 locations over a linear extension of 300m the phase reference signal with a jitter and drift lower than 30fs. The optical timing system is used to synchronize the 15 RF power plants used to accelerate the electrons, the laser systems operating in the facility as well as the femtosecond longitudinal diagnostics. Finally, some of the femtosecond class time domain longitudinal diagnostics are presented; these are of fundamental importance to validate the timing system itself and to monitor in real time its operation. Results of measurements done with beam are presented as well.