Bunch length and phase stability measurements at the TESLA test facility

Electron bunch lengths and time jitters have been measured with sub-ps resolution at the TESLA Test Facility at DESY. Synchrotron radiation emitted from a dipole magnet reflects the longitudinal charge distribution of the electron bunch and can also be used as a timing reference of the radiation pulses produced by the free-electron laser. For sub-ps time resolution, dispersion effects of the spectrally broad-band synchrotron radiation have to be suppressed. The phase stability of the FEL pulses with respect to the radio-frequency master oscillator has been studied with a streak camera operating in synchroscan mode.