The GSI 36 MHz high-current IH-type RFQ and HIIF–relevant extensions

The GSI High-Current Injector linac for ions with mass to charge ratios up to 65 and beam intensities up to 16 mA is under construction and will deliver beam in 1999. The first section of that linac is a 36 MHz RFQ cavity with a total length of 9.2 m and an energy range from 2.2 to 120 keV/u. It will be the first RFQ in H110-mode operation. The advantages of that RF structure for the acceleration of very heavy ion beams are outlined. MAFIA calculations are compared with the results from bead pull measurements of the completed cavity. Possible extensions of that type of RF structure towards a multibeam cavity are discussed.