Three phase R.F. systems for superconducting cyclotrons

This article describes and illustrates the three phase r.f. system for superconducting cyclotrons. It is discussed that the initial design of the MSU K500 cyclotron r.f. system has since been changed and these changes are reviewed. The author describes how, after several evolutions, there is now a successful moving short for the 6 dee stems. The stem current flowing on the 4-inch O.D. inner conductor is 2600 amps RMS, resulting in a linear current density of 206 amps per inch. Problems with the operation of the r.f. system are also reviewed