The VUV FEL at the TESLA Test Facility at DESY

It has been shown that the FEL at the TESLA Test Facility at DESY is an outstanding, presently unrivaled radiation source. The Phase I FEL experiments including the detailed characterisation of the VUV radiation ended in March 2002. In a second step (TTF 2) the maximum energy of the TTF linac will be increased to at least 1.0 GeV by adding additional rf accelerator modules. This facility will then serve a dual purpose: Beside offering a final test of the TESLA components it is also the basis for a world wide unique user facility providing FEL radiation from the VUV up to the soft X-ray region. The minimum wavelength will be about 6 nm. in the fundamental of the FEL and reach the water window in the higher harmonics. It is planned to deliver beam for users in early 2004.