WEOBB03
SLAC, Menlo Park, California, USA
DESY, Hamburg, Germany
We report on measurements of the longitudinal phase space profile of the bunch as it evolves along the length of the LCLS undulator. An x-band transverse deflecting cavity downstream of the undulator makes time resolved energy profile measurements with fs resolution. The electron energy loss mechanism of the FEL process is observed and allows us to reconstruct the temporal profile of the x-ray pulse on a shot by shot basis. We have been able to observe with unprecedented resolution microbunching in the beam and resonant energy loss leading to exponential gain and saturation in the FEL, as well as provide the users with the temporal profile of the x-rays on every shot.
