NEW EXPERIMENTAL RESULTS FROM PITZ*

The Photo Injector Test facility at DESY, Zeuthen site, (PITZ) was built to develop and optimize high brightness electron sources for Free Electron Lasers (FELs) like FLASH and the European XFEL. Last year, an electron beam with a very low transverse projected emittance of 1.26 mm mrad for 1 nC charge (100 % RMS) was demonstrated [1, 2, 3]. In the shutdown last winter, a major upgrade of the facility took place where many new diagnostics elements were installed and almost all components in the beamline were repositioned. In addition, a new RF gun cavity with improved water cooling was installed and conditioned. It is the first RF gun where the surface cleaning was done with a dry-ice technique instead of high-pressure water rinsing. It showed a 10 times lower dark current emission than its precursor gun, even at cathode gradients as high as 60 MV/m. Also a new photo cathode laser system with higher bandwidth was installed, which so far has produced Gaussian laser pulses of 2.1 ps FWHM. This contribution will summarize the transverse emittance measurements in 2007, the upgrade of the facility, dark current measurements from the new dry-ice cleaned RF gun cavity and quantum efficiency measurements of Cs2Te photo cathodes