How the optical timing system, the longitudinal diagnostics and ...

FERMI, the seeded free electron laser (FEL) in operation in Italy, is providing the User Community with unique fully coherent radiation, in the wavelength range 100–4 nm. FERMI is the first FEL fully synchronized by means of optical fibers. The optical timing system ensures an ultra-stable phase reference to its distributed clients. Several femtosecond longitudinal diagnostics verify the achieved performance; the bunch length monitor (BLM) and the bunch arrival monitor (BAM) will be presented in