Development of a Normal Conducting CH-DTL

The normal conducting "Crossbar H-Type" (CH) accelerating structure is a good candidate for pulsed, high intensity linacs application, covering the energy range from 3 to 100 MeV. H Mode cavities are outstanding in the low-beta range with respect to shunt impedance, high acceleration fields, and compact design: that\´s why we propose to base the 70 mA, 70 MeV, 352 MHz proton linac for the GSI FAIR project on that structure. The actual design consists of 11 CH-DTL\´s with a total length of around 20 m. Latest results from beam dynamics optimisation will be discussed. Moreover, this paper describes the CH-DTL cavity design with emphasis on the optimisation with Microwave Studio and on the achieved progress in the development of mechanical design concepts. A stainless steel multicell model cavity is presently fabricated by our institute in collaboration with GSI, in order to investigate manufacturing and assembly details. Based on this experience, the design of a CH prototype power cavity will be optimised.