Fully intensity and timing jitter compensated ultra-fast experiments at accelerator-driven photonsources at high repetition rates

Timing jitter and power instabilities are crucial parameters which greatly reduce the applicability of accelerator driven light sources for time-resolved experiments. In this contribution we present a technique that allows achieving few 10 fs time-resolution in experiments operating at cw repetition rates of up to 100 kHz by employing high repetition rate data acquisition. The method employs a fs-level arrival time monitor based on electro-optic sampling of residual pulses from a coherent diffraction radiator and a fast THz detector allowing for pulse to pulse detection of arrival time and pump intensity. The monitor can operate at high repetition rates cw (presently up to a few 100 kHz) and low electron bunch charges (sub pC). The prototype device has been tested at the quasi CW SRF accelerator (ELBE) by performing an ultra-fast THz driven magnetization dynamics experiment. Our method has high potential to provide few fs level timing on next generation large scale X-ray photon sources based on high repetition rate electron accelerators such as LCLSII. A demonstrator aiming at operation up to 4.7 MHz is under development for the European X-FEL.