Effective compact accelerating structures for heavy ions

The well known interdigital IH structure is now widely used for acceleration of heavy ions in low /spl beta/ range. Using the main idea of the IH cavities-transformation of the transverse RF voltage into a longitudinal accelerating one, but differing in realization of this principle, several RF structures are considered. In comparison with the IH cavities, the proposed versions originally have practically uniform field distribution along beam axis and no problems with end walls. With the small outer tank diameter, the effective shunt impedance is high enough. The design of the structures and preliminary results of optimization are presented.