\begin{table}%t3
\caption{Electron density derived from \ion{Mg}{viii}~lines ratios.
The 315.015~\AA\ and 335.231~\AA\ line intensities have been
corrected assuming that they are affected by blendings contributing
50\% and~20\% of the observed intensity, respectively. $C$ is the
correction factor applied to the line ratio to take blending into
account.}
\label{table:MgVIII_line_ratios}
%\centering
\par
\begin{tabular}{lll}
\hline  \hline
Ratio (\AA)      & $\log~N_{\rm e}$   & $C$ \\
\hline
311.772/313.743  & $\rm 7.7_{-0.3}^{+0.3}$ & 1.00 \\
315.015/313.743  & $\rm 7.8_{-0.2}^{+0.3}$ & 0.67 \\
335.231/313.743  & $\rm 7.8_{-0.5}^{+0.5}$ & 0.82 \\
338.983/313.743  & $\rm 7.8_{-0.5}^{+0.5}$ & 1.00 \\
317.028/315.015  & $\rm 7.7_{-0.2}^{+0.3}$ & 1.50 \\
335.231/315.015  & $\rm 7.7_{-0.4}^{+0.7}$ & 1.24 \\
338.983/315.015  & $\rm 7.8_{-0.4}^{+0.9}$ & 1.50\\
311.772/317.028  & $\rm 7.7_{-0.3}^{+0.3}$ & 1.00 \\
335.231/317.028  & $\rm 7.7_{-0.6}^{+0.5}$ & 0.82 \\
338.983/317.028  & $\rm 7.7_{-0.4}^{+0.6}$ & 1.00 \\
\hline
\end{tabular}
\end{table}