Bunch arrival-time monitor for synchronization of high power lasers and electron LINACs

The ELBE center of high power radiation sources at Helmholtz-Zentrum Dresden-Rossendorf combines a superconducting CW linear accelerator with Terawatt- and Petawatt-class laser sources. Key applications like the Thomson scattering x-ray source PHOENIX or external injection of electron bunches into a laser wakefield accelerator rely on precise timing and synchronization between the different radiation pulses.
An online single shot monitoring system has been set up measuring the timing between the high-power Ti:Sa laser DRACO and electron bunches generated by the conventional SRF accelerator. It uses a broadband RF pickup to acquire a probe of the particle bunch’s electric field and modulates a fraction of the high power laser pulse in a fast electro-optical modulator. The amplitude modulation gives a direct measure for the timing between both beams. Using this setup a resolution of <200 fs RMS has been demonstrated. The contribution will show the prototype, first measurement results and will discuss future modification in order to improve the resolution of the system.