Design of a new generation of collimators for LEP 200

One hundred and twenty six movable collimator blocks have been installed for the first phase of LEP. They have proved indispensable for providing good conditions for data taking of the experiments and gave no problems for running LEP. Sixty four additional movable blocks are planned to be added for the second phase of LEP (LEP 200 project). The collimators will consist of copper blocks with tungsten inserts or of spherical tungsten blocks. Their design is adapted to maintain the original low RF loss factor of 0.06 V/pC at the nominal aperture with reduced variations over the entire useful stroke.<
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