\begin{table}%t5
%\centering
\par
\caption{\label{tab-on1}List of log~$gf$ values for the \ioni{Si}{ii-iv} lines considered  in this study (from Atomic Line List v2.05). For the \ioni{O}{ii} lines we refer to \cite{Sim06}.}
\small  \begin{tabular}{ccccc}
\hline \hline \noalign{\smallskip}
Ion & $\lambda$ \AA & log~$gf$ & Configuration & Term \\
\hline
\noalign{\smallskip}
\ioni{Si}{ii} & 3856.02 & --0.4569 & 3s 3p$^2$-3s$^2$ (1S) 4p & 2D-2Po \\
\ioni{Si}{ii} & 3862.60 & --0.7130 & 3s 3p$^2$-3s$^2$ (1S) 4p & 2D-2Po \\ 
\ioni{Si}{ii} & 4128.10 &  0.3646 & 3s$^2$ (1S) 3d-3s$^2$ (1S) 4f & 2D-2Fo \\ 
\ioni{Si}{ii} & 4130.90 &  0.5192 & 3s$^2$ (1S) 3d-3s$^2$ (1S) 4f & 2D-2Fo \\
\ioni{Si}{ii} & 5041.02 &  0.2543 & 3s$^2$ (1S) 4p-3s$^2$ (1S) 4d & 2Po-2D \\
\ioni{Si}{ii} & 5055.98 &  0.5083 & 3s$^2$ (1S) 4p-3s$^2$ (1S) 4d & 2Po-2D \\
\ioni{Si}{ii} & 5056.32 & --0.4460 & 3s$^2$ (1S) 4p-3s$^2$ (1S) 4d & 2Po-2D \\
\ioni{Si}{ii} & 6347.11 &  0.1819 & 3s$^2$ (1S) 4s-3s$^2$ (1S) 4p & 2S-2Po \\
\ioni{Si}{ii} & 6371.37 & --0.1208 & 3s$^2$ (1S) 4s-3s$^2$ (1S) 4p & 2S-2Po \\
\noalign{\smallskip}
\ioni{Si}{iii} & 4552.62 &  0.2828 & 3s 4s-3s 4p & 3S-3Po \\
\ioni{Si}{iii} & 4567.84 &  0.0595 & 3s 4s-3s 4p & 3S-3Po \\
\ioni{Si}{iii} & 4574.76 & --0.4183 & 3s 4s-3s 4p & 3S-3Po \\
\ioni{Si}{iii} & 5739.73 & --0.1032 & 3s 4s-3s 4p & 1S-1Po \\
\noalign{\smallskip}
\ioni{Si}{iv} & 4088.86 &  0.1984 & 2p$^6$ 4s-2p$^6$ 4p & 2S-2Po \\
\ioni{Si}{iv} & 4116.10 & --0.1055 & 2p$^6$ 4s-2p$^6$ 4p & 2S-2Po \\
\ioni{Si}{iv} & 4212.40 &  0.3840 & 2p$^6$ 5d-2p$^6$ 6f & 2D-2Fo \\
\ioni{Si}{iv} & 4212.41 &  0.5601 & 2p$^6$ 5d-2p$^6$ 6f & 2D-2Fo \\
\ioni{Si}{iv} & 4631.24 &  1.2158 & 2p$^6$ 5f-2p$^6$ 6g & 2Fo-2G \\
\hline
\end{tabular}
\vspace*{2mm}
\end{table}