Werner Bräutigam1, Ronald Brings1, Ralf Gebel1, Helge N. Jungwirth1, *, Rudolf Maier1, Garrett de Villiers2
1 Institut für Kernphysik (IKP), Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany,
2 Accelerator Group, iThemba LABS, P.O. Box 722, Somerset-West 7129, South Africa,
* present address: ACCEL Instruments GmbH, D-51429 Bergisch Gladbach, Germany
Since January 1996, the cyclotron JULIC operates more than 7500 hours per year as injector of H- or D- beams for the cooler synchrotron COSY at the IKP of the Forschungszentrum Jülich. Usually about 8 mA of unpolarized or 1 mA of polarized H- ions are delivered at 45 MeV for charge-exchange injection into COSY; higher beam intensities would be required especially for polarized beams to fill COSY to its space-charge limit. Also unpolarized D- ions at 75 MeV were delivered with good results, although the septum-deflector insulators give problems at higher voltage. The demand for deuterons at COSY is growing, however, and the first polarized D- beam is already scheduled for tests. This report sums up the characteristics of the cyclotron in its present mode of operation and describes the quest for higher beam intensities as well as for providing D- beams reliably. The results are presented and discussed in terms of JULIC’s future suitability as COSY injector.