Feasibility studies for radioactive-ion storage ring

The low intensities of beams of unstable isotopes make it vital to use them efficiently. Their collection in a storage ring would open up a number of possibilities: higher beam intensities, enabling better suppression of background and more accurate measurement of isotopic and ionic properties; higher luminosities, by the use of beam cooling and internal targets; acceleration to higher energies; quasi-simultaneous operation with fixed-target experiments; and colliding- or merging-beam experiments with protons, electrons, muons, etc. The most crucial design aims are rapid accumulation of the beam and avoidance of beam spoilage and loss through interactions with strippers, residual gas and targets. This has led us to study injection by foil stripping and storage of the whole range of charge states produced, in the context of the ISAC radioactive beam facility at TRIUMF.