Progress and Perspective for High Frequency, High Performance Superconducting Ecr Ion Sources

Next-generation heavy ion beam accelerators require a great variety of high charge state ions with an order of magnitude higher beam intensity than is currently routinely available. Driven by this increasing demand for high performance ECR ion sources and enabled by advances in superconducting magnet technology, third generation superconducting (SC) ECR ion sources have been developed world-wide. The superconducting VENUS ECR ion source at the 88-Inch Cyclotron at the Lawrence Berkeley National Laboratory is the first ECR ion source designed for optimum operation at 28 GHz. Since it started operation in 2002 many world record ion beam intensities have been produced. VENUS has pioneered the field of high field SC ECR ion sources, and many of the design features and lessons learned during the VENUS commissioning phase have been incorporated in current 28 GHz ECR ion source projects such as GYROSERSE and SC-ECRIS. This paper will highlight recent progress on the VENUS ECR ion source for medium and high charge state production. In addition, it will discuss perspectives and main technical challenges of building 4th generation superconducting ECR ion sources using microwave heating frequencies of 56 GHz.