DETECTOR RESPONSE AND BEAM LINE TRANSMISSION MEASUREMENT WITH FAR-INFRARED RADIATION

Good understanding of radiation generation and transport mechanisms and of detector characteristics is essential in attempting to use frequency-domain techniques for longitudinal bunch diagnostics which are of crucial importance at short-wavelength free-electron lasers. This paper summarizes the current state of experimental verification of the far-infrared performance of a synchrotron radiation beam line at the TTF2 accelerator at DESY, Hamburg. Measurement of the polarization as function of frequency has also been found a useful tool to characterize the beam line. Furthermore, several approaches for detector response measurements are reported.