\begin{table}%t2
  \caption{\label{t2}Destruction cross-sections and sputtering yields obtained for CO experiments.}
  %\centering
\par
  \begin{tabular}{l l l l}
  \hline \hline\noalign{\smallskip}
  Projectile energy & CO column density              & Destruction cross-section & Sputtering yield            \\
  (MeV) & (10$^{17}$~molecules/cm$^{2}$) & ($10^{-14}$~cm$^{2}$)     & ($10^{4}$~molecules/impact) \\
  \hline
  50                & 16.3                          & 1$0.0 \pm 0.1$	 & $7 \pm 1$	               \\
  537               & 5.8                            & $3.5 \pm 1.0$	 & $5.8 \pm 0.4$	             \\
  537               & 10.4                           & $2.6 \pm 0.3$	 & $5.9 \pm 0.2$	             \\
  \hline
  \end{tabular}
\vspace*{-1mm}\end{table}