HLI The High Charge State Injector ( see Fig . 1 , and Table 1 ) is equipped with a Compacte A Plusieurs Résonances

The High Charge State Injector (HochLadungsInjektor) HLI was commissioned in 1991 [1]. It was the first linac comprising of a Radio Frequency Quadrupole RFQ and an Interdigital H-Type cavity IH. For more than twenty years, it successfully provided essential heavy ion beams with high duty cycle for several lighthouse experiments and developments at GSI. Among them are the Super Heavy Element Research SHE, namely the experiments SHIP, TASCA, SHIPTRAP, and the heavy ion cancer therapy. Three out of the six transuranium elements found at GSI were discovered with ion beams from the HLI [2]. The ever increasing demand for beam intensity was met by the proposal of a SuperConducting Continuous Wave sc cw-Linac. As the HLI will serve as an injector for this new accelerator, a cw upgrade for the HLI was developed.