Prototype Superconducting Triple-Spoke Cavity for Beta = 0.63

This paper reports the development status of a 345 MHz, three-spoke-loaded, TEM-class superconducting cavity with a transit-time factor peaked at = v/c = 0.63. The cavity has a 4 cm diameter beam aperture, a transverse diameter of 45.8 cm, and an interior length of 85 cm. The cavity is the second of two three-spoke loaded cavities being developed for the RIA driver linac and other high-intensity ion linac applications. Construction of a prototype niobium cavity has been completed and the cavity has been chemically processed. Results of initial cold tests are discussed.