Superconducting Cavities from High Thermal Conductivity Niobium for CEBAF

Abstract

The Continuous Electron Beam Accelerator Facility (CEBAF) is presently under construction in Newport News, VA.The accelerator consists of approximately 169 meters of 5-cell niobium cavities made from high thermal conductivity niobium with RRR values > 250.Cavities have been manufactured of material from three different suppliers.The material properties like thermal conductivity, residual resistivity and tensile behavior are compared.Results on the performance of these cavities in the presence of high rf fields are reported.Q(sub)0 values as high as 10^10 at 2 K and accelerating gradient of E > 14 MV/m have been achieved