Ion-induced triple fragmentation of CO 23+ into C++O++O+

Dissociation of CO${{}_{2}}^{3+}$ formed in fast, heavy-ion-induced ionization of CO${}_{2}$, using 5 MeV u${}^{\ensuremath{-}1}$ Si${}^{12+}$ ions as projectiles, has been studied by the technique of multi-ion coincidence momentum imaging. From the momentum correlation between the ejected ions, we conclude that dissociation of CO${{}_{2}}^{3+}$ into ${\text{C}}^{+}+{\text{O}}^{+}+{\text{O}}^{+}$ is a concerted process involving linear and bent conformations of CO${{}_{2}}^{3+}$. The kinetic-energy-release spectrum of the dissociation channel $\text{CO}{{}_{2}}^{3+}\ensuremath{\rightarrow}{\text{C}}^{+}+{\text{O}}^{+}+{\text{O}}^{+}$ is measured and the possible excited states of CO${{}_{2}}^{3+}$ are computed ab initio.