First operational experience with the positive-ion injector of ATLAS

The recently completed positive-ion injector for the heavy-ion accelerator ATLAS was designed as a replacement for the tandem injector of the present tandem-linac system and, unlike the tandem, the positive-ion injector is required to provide ions from the full range of the periodic table. The concept for the new injector, which consists of an ECR ion source on a voltage platform coupled to a very-low-velocity superconducting linac, introduces technical problems and uncertainties that are well beyond those encountered previously for superconducting linacs. The solution to these problems and their relationship to performance are outlined, and initial experience in the acceleration of heavy-ion beams through the entire ATLAS system is discussed. The unusually good longitudinal beam quality of ATLAS with its new injector is emphasized