Niobium Coating of Cavities Using Cathodic Arc

Niobium thin film coated copper RF cavities are an interesting alternative to niobium bulk cavities for the development of high performance superconducting accelerators. The main limiting factor in their use is the degradation of the quality factor Q with increasing accelerating field (the ldquoQ-Sloperdquo). To try and overcome this limitation, we have developed an alternative coating technique b...