A Compact 250-kV Injector System for PIGMI

A 250-kV proton injector to be used in the development of a linac suitable for medical applications has been constructed. This injector utilizes a spherical Pierce geometry to produce a converging beam. A gas insulated accelerating column is cantilevered on a grounded vacuum system, with a separate high voltage equipment dome connected to a 300-kV Cockcroft-Walton power supply. The injector can be operated locally or remotely, with the remote control accomplished by a microprocessor system linked to a central control minicomputer. This injector has been designed as a low-cost compact system. The design details and the data obtained during initial operation are presented.