Optical pumping of ions at storage rings

During the last decades, considerable attention has been paid to new opportunities that can be provided by spin-polarized ions beams at storage rings. These beams may be employed for investigating spin-dependent phenomena in atomic and nuclear reactions, measuring the parity violation effects in highly-charged ions, or for the search of a permanent electric dipole moment. In practice, however, there are two key issues which need to be solved before collision experiments with polarized ions will become accessible. Apart from the production of polarized ion beams, the preservation of their polarization during the round trips in the storage ring remains a crucial issue. In my talk, I will address both these issues in the light of an experiment made recently at the GSI storage ring in Darmstadt. This experiment has demonstrated how the polarization of ion beams can be created by means of the optical pumping of hyperfine ionic levels. Moreover, based on the theoretical analysis we argue that this polarization survives, at least partially, when ions pass through the bending and focusing magnets of the ring.