A MICROWAVE-DRIVEN NEGATIVE-ION SOURCE

A 2.45 GHz microwave-driven ion source, originally developed to genera te a high-current H-1(+) beam, has been adapted to serve as a universa l negative-ion injector for the Tandem Accelerator Superconducting Cyc lotron (TASCC) facility. Positive heavy ion currents from the source a re converted into negative currents by means of a charge-exchange cana l. So far, beams of He-4(-), O-16(-), and O-18(-) have been accelerate d through the TASCC Tandem and He-3(-) and Bi-209(-) beams were accele rated through both the TASCC Tandem and cyclotron. A production versio n of the source has been designed, with emphasis on enhanced compactne ss and serviceability. (C) 1996 American Institute of Physics.