Target Ionization in Collisions with Few-keV Molecular Ions*

The dominant channel in slow (few keV) collisions between a molecular ion and a target atom is dissociative capture, $e.g.$ H$_{2}^{+}$ + Ar $\to $ H + H + Ar$^{+}$. Our coincidence imaging method allows us to collect all three collision products and therefore determine the efficiency of detecting the recoil ion. Using that efficiency, we measure the probability of target ionization ($e.g.$ H$_{2}^{+}$ + Ar $\to $ H + H$^{+}$ + Ar$^{+ }$+ e$^{- })$ relative to all collision induced dissociation ($e.g.$ H$_{2}^{+}$ + Ar $\to $ H + H$^{+}$ + Ar$^{ }$+ e$^{-}$, H + H$^{+}$ + Ar$^{+ }$+ e$^{-})$. We find that the probability for target ionization, and by implication target excitation, is greater than 10{\%} and therefore should not be neglected in theory calculations.