Speaker
Description
800 MHz bulk niobium superconducting RF cavities are a fundamental, and sizeable, component of the FCC machine at all operating points. In the Booster, for Z, W, and H operating points, there are 112 cavities in 28 cryomodules. For TTbar operation, there will be a total of 448 cavities in the booster in 112 cryomodules, The FCC cavity performance specifications currently sit at the upper limit of what present-day techniques can achieve, and still incur a high RF power budget, in addition to generating substantial static and dynamic heat loads per cavity, driving up cryogenic costs. In order to deliver the most cost-effective and feasible version of the FCC, R&D efforts on 800 MHz SRF cavities and cryomodules have begun, focusing on advanced surface treatments for bulk niobium on 5-cell and single-cell 800 MHz prototypes. We report the first cold test results of these prototypes, and propose a course for future development. In addition, FNAL is collaborating with CERN on the mechanical design of the 6-cell 800 MHz cavities and cryomodules, based on experience with PIP-II designs and production. We thus also present updates and future plans for 800 MHz SRF CM R&D for FCC.
