PROTOTYPING OF A SUPERCONDUCTING ELLIPTICAL CAVITY FOR A PROTON LINAC∗

An L-band superconducting cavity has been designed for acceleration of particles travelling at 81 % the speed of light (β = 0.81). Four single-cell prototypes have been being fabricated and tested. Two of these cavities were formed from standard high purity fine grain niobium sheet. The rest were fabricated from large grain niobium. The RF per-formance of the single-cell cavities indicate that the design is suitable for use in a proton linac; the highest measured accelerating gradient was about 28 MV/m. The fabrication of two 7-cell cavity prototypes is in progress