Laser pulse timing synchronization to an electron bunch for Compton scattering

Precise synchronization of an electron bunch and a laser pulse is required to generate an X-ray pulse by 90° inverse Compton scattering. The stability of a mode-locked oscillator is primarily essential for the total laser system. We minimized the pulse timing fluctuation of a mode-locked Ti:sapphire oscillator using a low-noise all-solid-state pumping source to reduce the gain fluctuation and to control the position of a mirror to stabilize the cavity length with an active feedback. The short-term jitter was reduced to 77 fs and the long-term frequency drift was reduced to 70 μHz.