DEVELOPMENT OF A 130-MA, 75-KV HIGH-VOLTAGE COLUMN FOR HIGH-INTENSITYDC PROTON INJECTORS

A reliable high-voltage (KV) column has been developed for de proton i njectors with applications to high-intensity cw linacs. The HV column is coupled with a microwave-driven plasma generator to produce a 75-ke V, 110-mA de proton beam. Typical proton fraction from this source is 85%-90%, requiring the HV column and accelerating electrodes to operat e with a 130-mA hydrogen-ion beam current. A glow-discharge, which was caused by the ion source axial magnetic field, was initially observed in the HV column. This problem was solved by scaling the electron pro duction processes, the magnetic field, and the HV column pressure into a favorable regime. A subsequent 168 h reliability run on the 75-keV injector showed that the ion source (plasma generator and HV column) h as >98% beam availability. (C) 1998 American Institute of Physics.