| Paper |
Title |
Page |
| MOPCH011 |
Jitter Measurement by Spatial Electro-optical Sampling at the Flash Free Electron Laser
|
71 |
| |
- A. Azima, S. Düsterer, J. Feldhaus, H. Schlarb
DESY, Hamburg
- A.L. Cavalieri
MPQ, Garching, Munich
- D. Fritz
Michigan University, Ann Arbor, Michigan
- K. Sengstock
Uni HH, Hamburg
|
|
| |
For pump-probe experiments carried out at the VUV-FEL at DESY, FEL laser pulses with 32 nm wavelength have to be synchronized with high precision to optical laser pulses generated by a TiSa oscillator. To measure the relative timing variations between the FEL and the optical laser, an electro-optical experiment to determine the electron beam arrival time at the undulator has been installed. Here, the electron beam profile is encoded spatially into the laser pulse and readout by an intensified camera. A similar experimental setup has been successfully used at the sub-picosecond pulsed source (SPPS) at higher charge and shorter rms bunch length. In this paper, we report about the achievements and difficulties of the Timing Electro-Optical (TEO) setup, that allows to post-order experimental user data with a precision of 100 fs rms and better.
|
|
| TUPCH024 |
Comparative Study of Bunch Length and Arrival Time Measurements at FLASH
|
1049 |
| |
- H. Schlarb, A. Azima, S. Düsterer, M. Huening, E.-A. Knabbe, M. Roehrs, R. Rybnikov, B. Schmidt, B. Steffen
DESY, Hamburg
- M.C. Ross
SLAC, Menlo Park, California
- P. Schmüser, A. Winter
Uni HH, Hamburg
|
|
| |
Diagnostic devices to precisely measure the longitudinal electron beam profile and the bunch arrival time require elaborate new instrumentation techniques. At the VUV-FEL, two entirely different methods are used. The bunch profile can be determined with high precision by a transverse deflecting RF structure. The method is disruptive and does not allow to monitor multiple bunches in a macro-pulse train. Therefore, it is augmented by two non-disruptive electro-optical devices, called EO and TEO. The EO setup uses a dedicated diagnostic laser synchronized to the machine RF. The longitudinal electron beam profile is encoded in the intensity profile of a chirped laser pulse and analyzed by looking at the spectral composition of the pulse. The second setup, TEO, utilizes the TiSa-based laser system used for pump-probe experiments. Here, the temporal electron shape is encoded into a spatial dimension of laser pulse by an intersection angle between the laser and the electron beam at the EO-crystal. In this paper, we present a comparative study of bunch length and arrival time measurements performed simultaneously with all three experimental techniques.
|
|