Surface Preparation of Superconducting Cavities

Improved Surface Treatment of the Superconducting TESLA Cavities

The proposed linear electron-positron collider TESLA is based on 1.3 GHz superconducting niobium cavities for particle acceleration. For a center-of-mass energy of 500 GeV an accelerating field of 23.4 MV/m is required which is reliably achieved with a niobium surface preparation by chemical etching. An upgrade of the collider to 800 GeV requires an improved cavity preparation technique. In thi...

Surface Studies of Materials for Superconducting Cavities * I

A multitechnique system has been constructed to study materials and processes used for producing high Q superconducting cavities, while constantly maintaining UBV environment. Characterization of a small disc of superconducting material, e. g. Nb, is done by a variety of methods, including AES, XPS, EID, ellipsometry, sputter profiling, and secondary electron yield measurements. The samples may...

Surface Superconductivity in Niobium for Superconducting RF Cavities

A systematic study is presented on the superconductivity (sc) parameters of the ultrapure niobium used for the fabrication of the nine-cell 1.3 GHz cavities for the linear collider project TESLA. Cylindrical Nb samples have been subjected to the same surface treatments that are applied to the TESLA cavities: buffered chemical polishing (BCP), electrolytic polishing (EP), low-temperature bakeout...

Superconducting cavities for accelerators

Superconducting cavities have been in operation in accelerators for 25 years. In the last decade many installations in storage rings and linacs have been completed. Meanwhile, nearly 1 km of active cavity length is in operation in accelerators. Large-scale applications of superconducting radiofrequency systems are planned for future e+e− linear colliders and proton linacs. Superconducting cavit...

Demonstration of superconducting micromachined cavities