The S-Band Linear Collider Test Facility at DESY

The S-Band Linear Collider Test Facility under construction at DESY serves as a test bed for the essential hardware to build a large scale e/sup +/e/sup -/ linear collider based on a 3 GHz accelerating RF and having a center of mass energy of at least 500 GeV. Besides the injection system at the beginning and a beam analysis area at the downstream end, the central part of the test facility consists of two modular units similar to those to be installed in a S-Band Linear Collider (SBLC) tunnel. The key-questions of Higher Order Mode (HOM) excitation, measurement, damping and feedback on the alignment of the accelerating structure as well as the quadrupole position have to be answered in order to manage the most crucial aspect of a 15 km linear accelerator, namely the beam stability. The final layout of this test facility and the performance of the present setup including the first accelerating section fed by a 150 MW klystron is presented.