Ion source and stripper gas cell developments for the 6 MeV tandem heavy ion beam probe on the Large Helical Device

The feasibility of a heavy ion beam with a tandem acceleration system for plasma potential measurement has been examined. A plasma-sputter-type ion source which produces an Au/sup -/ beam with an energy width as small as 6 eV and a reasonably small emittance of /spl pi/ mm-mrad (MeV)/sup 1/2 /, can be used for this purpose. Suitable target gas thickness for a charge exchange is estimated to be less than 10/sup 15/ atom/cm/sup 2/ at the 3 MV terminal voltage.<
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