Recent Developments on Superconducting CH-Structures and Future Perspectives

Worldwide there is an increasing interest in new high intensity proton and ion driver linacs with beam powers up to several MW. A very challenging part of these accelerators is the low and medium energy section up to 100 MeV. Depending on the duty cycle room temperature or superconducting options are favoured. In both cases the Crossbar-H-mode (CH)-structure developed at the IAP in Frankfurt is an excellent candidate. Room temperature as well as superconducting prototype cavities have been developed and tested successfully. A superconducting 19 cell low energy CH-cavity at 360 MHz reached effective gradients of 7 MV/m corresponding to an accelerating voltage of 5.6 MV. This cavity could be used for high intensity, cw operated linacs like accelerator driven systems (ADS, EUROTRANS) or the international fusion material irradiation facility (IFMIF). Recent developments of this new type of a multi-cell drift tube cavity, tests of the prototypes and future plans will be presented.