\begin{table}%t2 \caption{\label{tab:lines}Lines studied in the present work and their parameters. } %\centerline {\small \begin{tabular}{ccrrr} \hline\hline Atomic species & $\lambda$ [nm] & $\log gf$ & $E_{{\rm low}}$ [eV] & $W_{\mu=1}$ [pm] \\ \hline Fe~\textsc{i} & 615.1618$^{\rm{c}}$ & --3.299$^{\rm{b}}$ & 2.18$^{\rm{b}}$ & 4.95\\ Si~\textsc{i} & 615.5693$^{\rm{a}}$ & --2.252$^{\rm{a}}$ & 5.62$^{\rm{a}}$ & 0.61\\ Ca~\textsc{i} & 615.6023$^{\rm{a}}$ & --2.497$^{\rm{a}}$ & 2.52$^{\rm{a}}$ & 0.92\\ Fe~\textsc{i} & 615.7728$^{\rm{c}}$ & --1.260$^{\rm{a}}$ & 4.08$^{\rm{b}}$ & 6.45\\ O~\textsc{i} & 615.8186$^{\rm{b}}$ & --1.841$^{\rm{b}}$ & 10.74$^{\rm{b}}$ & 0.63\\ Fe~\textsc{i} & 615.9378$^{\rm{c}}$ & --1.970$^{\rm{a}}$ & 4.61$^{\rm{a}}$ & 1.21\\ %\hline Fe~\textsc{i} & 629.0965$^{\rm{a}}$ & --0.774$^{\rm{a}}$ & 4.73$^{\rm{a}}$ & 7.06\\ Fe~\textsc{i} & 629.7792$^{\rm{b}}$ & --2.740$^{\rm{b}}$ & 2.22$^{\rm{b}}$ & 7.54\\ $\rm [O~\textsc{i}]$ & 630.0304$^{\rm{b}}$ & --9.717$^{\rm{d}}$ & 0.00$^{\rm{b}}$ & 0.45\\ Sc~\textsc{ii} & 630.0698$^{\rm{a}}$ & --1.887$^{\rm{a}}$ & 1.51$^{\rm{a}}$ & 0.59\\ %\hline O~\textsc{i} & 777.1944$^{\rm{b}}$ & 0.369$^{\rm{b}}$ & 9.15$^{\rm{b}}$ & 8.48\\ O~\textsc{i} & 777.4166$^{\rm{b}}$ & 0.223$^{\rm{b}}$ & 9.15$^{\rm{b}}$ & 7.44\\ O~\textsc{i} & 777.5390$^{\rm{b}}$ & 0.002$^{\rm{b}}$ & 9.15$^{\rm{b}}$ & 5.90\\ Fe~\textsc{i} & 778.0557$^{\rm{a}}$ & 0.029$^{\rm{a}}$ & 4.47$^{\rm{a}}$ & 14.81\\ \hline \end{tabular}} \medskip Equivalent widths at disk-centre measured from our observations. Data sources: a)~VALD database; b)~NIST database; c) \citet{Nave1994}; d)~\citet{Storey2000}. \end{table}