Kinetic energy release of dissociating CO3+ions produced in collisions of multiply charged ions with CO

We investigate fragmentation of CO molecules by collisions of He2+ ions at energies between 2 and 11 keV/amu by means of a reflectron time-of-flight (TOF) spectrometer. The kinetic-energy-release (KER) in the center of mass system of the molecule can be determined from the flight times of these particles. Different dissociation processes leading to different amounts of released energy and different fragments can be identified. The KER differs from the one expected from the pure Coulomb repulsion of two point charges, starting at the CO equilibrium distance and depended strongly on the collision energy. This will be discussed in terms of the classical overbarrier model. Furthermore, there is a strong influence of the projectile type on the KER. A feature of the experiments, namely the strong dependence of the KER on the projectile kinetic energy, is not yet fully understood.