Low cross section experiments to produce super-heavy elements have increased the demand for high intensity heavy ion beams at energies of about 5 MeV/nucleon at the 88-Inch Cyclotron at the Lawrence Berkeley National Laboratory. Therefore, efforts are underway to increase the overall ion beam transmission through the axial injection line and the cyclotron. The ion beam emittance has been measured for various ion masses and charge states. Beam transport simulations including space charge effects were performed for both of the injection line and the ion source extraction. The relatively low nominal injection voltage of 10 kV was found to be the main factor for ion beam losses, because of beam blow up due to space charge forces at higher intensities. Consequently, experiments and simulations have been performed at higher injection energies, and it was demonstrated that the ion beams could still be centered in the cyclotron at these energies. Therefore, the new injector ion source VENUS and its ion beam transport system (currently under construction at the 88-Inch Cyclotron) are designed for extraction voltages up to 30 kV.

VENUS (Versatile ECR ion source for NUclear Science) is a next generation superconducting ECR ion source, designed to produce high current, high charge state ions for the 88-Inch Cyclotron at the Lawrence Berkeley National Laboratory. VENUS also serves as the prototype ion source for the RIA (Rare Isotope Accelerator) front end. The magnetic confinement configuration consists of three superconducting axial coils and six superconducting radial coils in a sextupole configuration. The nominal design fields of the axial magnets are 4T at injection and 3T at extraction; the nominal radial design field strength at the plasma chamber wall is 2T, making VENUS the world most powerful ECR plasma confinement structure. The magnetic field strength has been designed for optimum operation at 28 GHz. The four-year VENUS project has recently achieved two major milestones: The first plasma was ignited in June, the first mass-analyzed high charge state ion beam was extracted in September of 2002. The paper describes the ongoing commissioning. Initial results including first emittance measurements are presented.