Characterization of the arrival time jitter at the MAX-lab test-FEL using electro-optical spectral decoding

Electro-optical spectral decoding is used as an online diagnostic tool at the MAX-lab test-FEL to characterize the arrival time of electrons relative to the seed-laser pulse, measure the jitter between them and to measure the relative width of the electron bunch in order to optimize compression. Frequency characteristics of the jitter are presented. The measurements are used to get information on possible causes of the jitter and accompanying drifts.