PRODUCTION OF HIGHLY-CHARGED ION-BEAMS FROM ELECTRON-CYCLOTRON-RESONANCE ION SOURCES (INVITED)

Electron cyclotron resonance ion source (ECRIS) development has progre ssed with multiple-frequency plasma heating, higher mirror magnetic fi elds, and better technique to provide extra cold electrons. Such techn iques greatly enhance the production of highly charged ions from ECRIS s. So far at continuous wave (CW) mode operation, up, to 300 e mu A of O7+ and 1.15 emA of O6+, more than 100 e mu A of intermediate heavy i ons for charge states up to Ar13+, Ca13+, Fe13+ Co14+, and Kr18+, and tens of e mu A of heavy ions with charge states to Kr26+, Xe28+, Au35, Bi34+, and U34+ were produced from ECRISs. At an intensity of at lea st 1 e mu A, the maximum charge state available for the heavy ions are Xe36+, Au46+, Bi47+, and U48+. An order of magnitude enhancement for fully stripped argon ions (I greater than or equal to 60 enA) were als o achieved. This article will review the ECR ion source progress and d iscuss key requirement for ECRISs to produce the highly charged ion be ams. (C) 1998 American Institute of Physics.