\begin{table}%T1
\par
\caption{\label{t1}Quotients $Q$ for set of the six Si~I spectral lines.}
%\centerline
 {
\begin{tabular}{ccccccc}
\hline\hline
$p$& 250.690 & 251.432& 251.611 & 251.920 &  252.411& 252.851 
\\
\cline{1-1}
$q$\\
\hline
250.690&1&  &  &  &  &  \\
251.432&0.87&1&  &  &  &  \\
251.611&1.18&1.33&1&  &  &  \\
251.920&--&--&--&1&  &  \\
252.411&--&--&--&0.95&1&  \\
252.851&--&--&--&0.95&1.18&1 \\
\hline
\end{tabular}}
\medskip
\par
Note 1. The quotients $Q_{p,q}=R^{\rm m}_{p,q}/R^{\rm th}_{p,q}$ of the
measured intensity ratios $R^{\rm m}_{p,q}=I_p/I_q$ and theoretical
$R^{\rm th}_{p,q}=A_pg_p/A_qg_q$ for the six Si~I~spectral lines from
the resonance $\rm 3s^23p^2 {-} 3s^23p4s$ transition. The transition
probabilities~$(A)$ and statistical weights~$(g)$ are taken from
NIST (\cite{NIST09}). Every cell contains quotient $Q_{p,q}$ calculated for
particular pair of spectral lines $p$ and $q$, measured at the
same temperature. The first group of three lines (250.690~nm,
251.432~nm, 251.611~nm) is recorded at $T=15~000$~K, the second
group (251.920~nm, 252.411~nm, 252.851~nm) is recorded at $T=12~500$~K.
\end{table}