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The dissociation of ions produced in collisions of ions with CO has been studied by time-of-flight measurements. Both singles and coincidence time-of-flight techniques have been used to determine the kinetic energy release of the dissociating CO molecules. We describe the method to transform the singles and coincidence time-of-flight spectra into total kinetic energy distributions and discuss these distributions. They represent kinetic energy release distributions which clearly exhibit various contributions associated with different dissociation channels. In comparison with other ionization methods similarities but also clear differences are noted.

State-selective charge transfer and target excitation in collisions of He2+ ions with Na has been studied by means of far ultraviolet and visible light spectroscopy. Generally, the experimental results confirm the theoretical predictions by Shingal et al. (1987) for electron capture and for the dominant excitation channel, Na(3p). However in the lower half of the impact energy range studied, 2-9 keV amu-1, discrepancies in energy dependence and absolute magnitude (up to a factor of approximately 6) are found for the Na(4p) and Na(4d) excitation channels.

By means of photon emission spectroscopy we have studied state selective oneelectron capture and target-ion excitation in collisions of He2+ with He, The collision energy has been varied from 1 to 75 k V m u -' . Four-body classical Vajectory Monte Carlo calculations have been performed in the energy range of 5&300 keV mu-'. In the energy range where experiment and theory overlap there is in general fair agreement. allhough the 1-distributions within a principal quantum shell exhibit differences. At energies below SO keV am-' the experiments confirm the results of atomic orbital calculations. presented in an accompanying paper by Fritsch. Combining all the experimental and theoretical data we have determined a reliable cross section data bwe for use in neutral helium beam based plasma diagnostics on large tokamaks.