\begin{table}%t11
\caption{\label{TabCX}Charge exchange reaction rates relevant to the post-shock PIR in an oxygen-dominated medium.}
%\centerline
 {\small \begin{tabular}{lllll}
\hline\hline\noalign{\smallskip}
 Reaction
   & $\Delta E$, eV & $\delta E$, eV & $\alpha_{\rm CX}$, cm$^3$/s
   & Emitted lines; notes \\
\hline\noalign{\smallskip}
O$^+$ + C$^0$ $\to$ O$^0$($^1$D) + C$^+$
   & 2.36 & 0.39 & $1\times10^{-9}$ &
   [\ion{O}{i}] 6300, 6363~\AA\\
%
O$^+$ + Si$^0$ $\to$ O$^0$ + Si$^+$(3s 3p$^2$ $^4$P)
   & 5.47 & 0.15 & $3\times10^{-9}$ &
   [\ion{Si}{ii}] 2329--2351~\AA\\
%
O$^+$ + S$^0$ $\to$ O$^0$ + S$^+$($^2$P)
   & 3.26 & 0.22 & $3\times10^{-9}$ &
   [\ion{S}{ii}] 4069, 4076, 6716, 6731, 10~287--10~370~\AA\\
%
O$^+$ + Fe$^0$ $\to$ O$^0$ + Fe$^+$ (excited)
   & 5.72 & many transitions & $1.7\times10^{-9}$ &
   multiple lines; rate from \citet{Rutherford72}\\
\hline
\end{tabular}}
\medskip
Notes: it is assumed that the atoms and ions are in their
ground states (or excited fine-structure states) before the
charge-exchange reaction. $\Delta E$ denotes the difference in the
ionization potentials of atom and ion in their ground states,
$\delta E$ denotes the same difference for outgoing atom and ion in
specified states, and $\alpha_{\rm CX}$ is the charge exchange rate
estimate. Only excited state classification is shown.
\end{table}