• U. Laier, P. Hülsmann, K.-P. Ningel, G. Schreiber
  GSI, Darmstadt

The 'Facility of Antiproton and Ion Research' (FAIR) project will be realized at the 'GSI Helmholtzzentrum für Schwerionenforschung GmbH' (Darmstadt, Germany) in the scope of a large international collaboration. One of the FAIR storage rings is the collector ring (CR) whose main purpose is to allow a fast cooling of secondary beams (rare isotopes and antiprotons). The RF system of the collector ring has to allow pulsed operation (40kV, duty cycle 5e-4) as well as continuous operation (2kV) in the frequency range of 1.2 to 1.4MHz. The detailed conceptual design of this RF system is introduced here. It will be based (similar to the existing RF system 'SIS18 bunch compressor' which will also be presented at PAC09) on two inductively loaded quarter wavelength coaxial resonators operating on a common ceramic gap. The resonator will be loaded with twelve ring cores (rout=313mm, rin=145mm, h=25mm) of a cobalt based amorphous magnetic alloy (VitroVac6030F); it will be cooled by forced air. The cavity will be driven by a push-pull amplifier operated in class A consisting of two tetrodes (TH555A) that will be coupled inductively to the cavity.

• M. Mehler, H. Klingbeil, M. Kumm, U. Laier, K.-P. Ningel
  GSI, Darmstadt

Funding: Project funded by the European Community under the FP6 "Structuring the European Research Area" program (SIS100₂, contract number 515873)

SIS100 is a synchrotron that will be built in the scope of the FAIR (Facility for Antiproton and Ion Research) project. High intensity ion beams are required, making it necessary to damp longitudinal coupled and uncoupled bunch oscillations. For this purpose, a closed-loop control system was designed. Its processing part is based on digital signal processors (DSP) and field programmable gate arrays (FPGA) whose advantage is their adaptability to different problems by software changes. Experiments with a prototype were performed at the existing synchrotron SIS12/18 at GSI concentrating on the damping of longitudinal coupled bunch quadrupole oscillations of the lowest order. The configuration of the electronic system is described and results of the machine development experiments are reported. Finally, an outlook to the application in SIS100 is given.