\begin{table}%t3
\caption{\label{tab:uncer}Uncertainties of the atmospheric parameters and of the equivalent widths.}
\small
%\centering
\par
\begin{tabular}{c c c c}
\hline\hline\noalign{\smallskip}
Parameter & $\sigma$ & Range of {\it EW} & $\sigma$ \\
\hline
$T_{\rm eff}$ (K) & $\pm$50 & {\it EW} $<$ 150 m\AA & $\pm$3 m\AA  \\
$\log g$ (dex) & $\pm$0.35 & 150 m\AA  $<$ {\it EW} $<$ 400 m\AA & $\pm$10 m\AA  \\
$\xi$ (km~s$^{-1}$) & $\pm$0.06 & {\it EW} $>$ 400 m\AA & $\pm$20 m\AA \\
\hline
\end{tabular}
\end{table}