Superconducting spoke cavities for high-velocity applications

To date, superconducting spoke cavities have been designed, developed, and tested for particle velocities up to β_{0}∼0.6, but there is a growing interest in possible applications of multispoke cavities for high-velocity applications. We have explored the design parameter space for low-frequency, high-velocity, double-spoke superconducting cavities in order to determine how each design parameter affects the electromagnetic properties, in particular the surface electromagnetic fields and the shunt impedance. We present detailed design for cavities operating at 325 and 352 MHz and optimized for β_{0}=0.82 and 1