Experimental Investigations on Electron Capture in the Presence of Metastable Ion Beam Fractions

A survey is given of experimental methods for absolute determination of metastable ion beam fractions which are of interest for studies on electron capture in ion-atom collisions. Particular emphasis is given to new results about the extent to which primary ion state conservation in single electron capture processes can be useful for measuring metastable beam fractions for low lying excited levels. Furthermore, detection of highly excited metastable final states resulting from electron capture is discussed in connection with translational energy spectroscopy.