Highly-charged ions in traps - Progress and opportunities

Penning and Kingdon ion traps have been used to study low-energy multiply-charged ions with charge states up to 80+ during the last few years. The ions have been captured into the traps from beams of external multiply-charged ion sources, or have been produced inside the trap. Measurements of cross sections for electron capture from neutrals to ions and studies of relative double electron capture rates have been completed. The lifetimes of metastable levels of ions, precision spectroscopy on multiply-charged ions in traps, and cooling of trapped ions using lasers, ion-ion elastic collisions, and parallel-tuned circuits, are briefly reviewed. Prospects for the future of highly-charged ions in traps are also discussed.