Cyclotrons in 1986

Fifty-six years after their invention, the design, construction and improvement of cyclotrons continues at a healthy rate, while their capabilities continue to be extended. Six projects have been completed within the last two years, 13 are under way and 4 more have been approved. The trend is more and more to use superconducting magnets, and in one case a superconducting rf cavity also. The advent of efficient, though expensive, ECR ion sources capable of producing highly stripped heavy ions has killed many PIG sources and is likely to do the same to a number of injector accelerators. Cooling rings, which can store, cool and accelerate beam from a cyclotron, promise powerful improvements in performance and are becoming increasingly popular; five are under construction and more are being proposed. The challenge of high intensity has revealed new problems and provoked new solutions in both beam dynamics and rf control. (author)