TEST AND FIRST EXPERIMENTS WITH THE NEW REX-ISOLDE 200 MHZ IH STRUCTURE *

For the REX-ISOLDE accelerator, a new accelerating structure is at the moment installed and tested. It will raise the final energy from the present 2.3 MeV/u to 3 MeV/u. The aim is to increase the mass range of the nuclei available for nuclear spectroscopy from mass 40 to mass 80. The new accelerator component is a 0.5 m IH- structure, working at the double REX frequency of 202.56 MHz. It was originally developed as a 7-Gap resonator for the MAFF (1) project and later adapted to the requirements at REX by changing from a 7-Gap to a 9-Gap resonator to match the lower injection energy. We present the design of the resonator and the results of the rf-tests, commissioning and first operation during the 2004 running period.