\begin{table}%t4
\caption{\label{tabellafinale}Best-fit parameters for the three components of the adopted Cloudy model used to fit the RGS data.}
\par
%\centerline
{\small
\begin{tabular}{cccccc}
\hline\hline
  &  {\bf $\log U$} & {\bf $\log (n_{\rm e}/{\rm cm^{3}})$}& {\bf $\log (N_{\rm H}/{\rm cm^{2}})$}& {\bf $d$} (pc) & {\bf $\Delta_{f=1}$} (pc)\\
 % &              & (cm$^{-3}$)    &  (cm$^{-2}$)   &  (pc)     &  (pc)        \\
  &              &     &     &       &          \\
%  &                 &                                 &                                 &          \\
\hline
 {\bf Low}      &  $0.63_{\rm -0.03}^{+0.05}$ & $\la  $5 & $22.10_{\rm -0.04}^{+0.30}$ & $\ga  $0.22& $\ga  $0.04\\
 {\bf High}     &  $1.90_{\rm -0.10}^{+0.20}$ & $\la  $5 & $22.72_{\rm -0.13}^{+0.25}$ & $\ga  $0.05& $\ga  $0.20\\
\hline
 {\bf Warm Abs.}      &  $0.85_{\rm -0.02}^{+0.02}$ & $\la  $7 & $23.36_{\rm -0.01}^{+0.01}$ & $\ga  $0.02& $\ga  $0.01\\
\hline
\end{tabular}}
\tablefoot{Errors are given at the 90\% confidence level for one interesting parameter. Columns are: the ionization parameter, electron density, Hydrogen column density, distance from the central ionizing source, and the average X-ray emitting source size evaluated as $\Delta\simeq N_{\rm H}/f n_{\rm e}$, where $f$ is the filling factor. Here, for simplicity we have assumed $f \simeq 1$.}\vspace*{-3mm}
\end{table}