Inspired by the production of NEG-coated vacuum chambers, this novel technique for high quality Nb/Cu cavities that can be used in FCC-ee has completed its first qualitative feasibility study.

Crab cavities are critical to increase the number of interactions. After successful prototyping and testing, the US programme has entered series production.

In a recent paper, the densification of coated Nb films on copper samples at 90deg angle of incidence was explored for different techniques.