H. Reich, P. Spaedtke (Gesellschaft fur Schwerionenforschung mbH, Planckstrasse 1, D-64291 Darmstadt, Germany)
The new high current injector consisting of an RFQ and an IH structure accepts ions with a mass-to-charge ratio m/q up to 65 with a space charge limit of 0.25 emA x m/q. For ions of gaseous elements a multi-cusp ion source (MUCIS) [1] was used, metallic ions were produced by a metal vapor vacuum arc ion source (MEVVA) [2]. The very stable operation of the MUCIS and an ion beam intensity well above the theoretical space charge limit of the RFQ, provided at the front of the RFQ, enabled ideal conditions for the commissioning of the new accelerator. Whereas the the total ion beam current extracted from both type of ion sources was appr. 100emA, the total ion beam current measured behind the accelerating gap was limited to appr. 50emA. To improve the transmission, calculations to optimize the accelerating gap geometry were performed. Beside technical details of the ion sources, measurements of ion beam parameters (intensity, pulse shape and emittance) will be presented for Ar1+(18emA)(MUCIS) and Ni1+(10emA),92Mo2+(1emA), U4+(6mA)(MEVVA).
[1] R. Keller, Multicharged ion production with MUCIS, GSI annual report 1987, p.360
[2] I.G. Brown, The Metal Vapor Vacuum Arc Ion Source, in The Physics and Technology of Ion Sources, ed. by I.G. Brown, Jaohn Wiley and Sons, New York, 1989
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