Recent developments in superconducting cyclotrons

Superconducting cyclotrons have come of age: three machines have been operating on a regular basis since several years. These first generation machines have benefited from improvement programs and new equipment, while proposals for further expansion of their capabilities have been elaborated. The most significant events of 1994 have been the first beams in two new machines: the AGOR cyclotron in Orsay (France) and the K800 cyclotron in Catania (Italy). The first beam of the machine in Catania, Ni ions at 30 MeV/A, crowned a long construction effort, requiring transport of the magnet from Milan and assembly of the accelerator at its final location on the island of Sicily. AGOR, the first machine of a new generation, accelerated and extracted α-particles with an energy of 50 MeV/A, proving the validity of a number of novel design features. The vitality of the concept of using superconducting coils in a cyclotron is demonstrated by new proposals for such machines, to be used in cancer therapy