Progress on the CLIC Final Focus System

The Final Focus System has been adapted to the revised parameter list for CLIC. It is expected that lower emittances are obtainable in the damping rings and the blowup in the main linac can be contained to 25%. Then the luminosity is no longer limited by synchrotron radiation in the final quadrupoles, and luminosity above 1033cm-2 s-1 could be reached for bunches colliding head on. However, finite crossing angles are required so the disrupted beam can pass through a special aperture in the first interaction region quadrupole. The reduction of luminosity due to this crossing angle and due to unavoidable misalignments has been studied as function of bunch length with a particle tracking code. Two designs of quadrupoles are presently being evaluated, one based on permanent magnets, and the other on pulsed currents. Results of measurements on models are presented