Large radio-frequency gas catchers and the production of radioactive nuclear beams

Abstract

Gas catchers provide a means to transform radioactive recoils from various production mechanisms into low-energy beams of good ion optical properties. Recent developments with large radio-frequency gas catchers have pushed back purity and space-charge limitations in this technology to the point that it can now be used reliably for producing radioactive beams intense enough for various secondary experiments to be possible. The basic technology available and the current demonstrated capabilities are presented in the following. A number of examples of such systems currently under commissioning/construction/design at ANL to produce beams from fusion-evaporation, fission, deep-inelastic and fragmentation reaction products will also be presented together with the specific challenges to each approach and the chosen solutions.