  We study excitation and ionization in the 1.5 MeV/amu O$^{8+}$-Li collision
system, which was the subject of a recent reaction-microscope-type experiment
[Fischer \textit{et al.}, Phys. Rev. Lett. \textbf{109}, 113202 (2012)].
Starting from an independent-electron model based on determinantal wave
functions and using single-electron basis generator method and continuum
distorted-wave with eikonal initial-state calculations we show that pure single
ionization of a lithium $K$-shell electron is too weak a process to explain the
measured single differential cross section. Rather, our analysis suggests that
two-electron excitation-ionization processes occur and have to be taken into
account when comparing with the data. Good agreement is obtained only if we
replace the independent-electron calculation by an independent-event model for
one of the excitation-ionization processes and also take a shake-off process
into account.
