\begin{table}%t1
%\centering
\par
\caption{Atomic constants for the \ion{Ru}{i} and \ion{Hf}{ii}
lines used in this work, and references for $\log gf$. "Sun''
denotes the $gf$-values fitted on the solar and Arcturus spectra.
Other $gf$-values were taken from VALD, \citet{lund06} (L06),
and \citet{lawler07} (L07).
\label{atcte}}
\begin{tabular}{lcccccc}
\hline\hline
\noalign{\smallskip}
 El. &  $\lambda$ (\rm \AA) & $\chi_{\rm ex} \rm (eV)$ & $\log gf$ & $\log gf$ & $\log gf$ & $\log gf$ \\
    &            &           & VALD   &  Sun & L06 & L07\\
\hline
\noalign{\smallskip}
Hf II & 4080.437 & 0.608 & ...    & --0.896 & --1.596  & --1.55 \\
Hf II & 4093.155 & 0.452 & --1.090 & ...    & ...     & --1.15 \\
Ru I  & 4080.574 & 0.810 & --0.040 & ...    & ...     &  ...  \\
Ru I  & 4757.856 & 0.928 & --0.890 & --0.540 & ...     &  ...  \\
\noalign{\smallskip}
\hline
\end{tabular}
\end{table}