FCC   FCCIS      

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Abstract (D5.S1)

The machine optics have been adapted to the new layout with eight surface sites instead of twelve, a circumference of about 91.1 km and a perfect four-fold superperiodicity, which allows either two or four collision points and experiments.

A new baseline layout has been developed for the pre-injector, where positrons are now generated at a primary electron beam energy of 6 GeV (previously 4.46 GeV) and each linac is operated only with a single unique energy profile; both these changes will boost the performance. A novel type of positron source is being developed for FCC-ee, a prototype of which will be constructed and later tested with beam, at the PSI SwissFEL at primary energies of between 0.5 and 6 GeV.