\begin{table}%t1
\caption{\label{tab:datasets}\caii~854.2 line scan sequences from June~2008.}
\par
\small%\centerline
 {
\begin{tabular}{ccccccc}
\hline \hline
&&&&&& \\[-8pt]
Data set &  $\mu$ & $\lambda$ & $(\Delta \lambda)_{\rm core}$$^a$&
 $(\Delta \lambda)_{\rm wing}$$^b$& $\Delta{t}$&  dur.\\
(date)&&[pm]&[pm]&[pm]&[s]&[min]\\
\hline
1~(13th)& 0.92&  --92.0--+19.4  & 4.8&  4.8&  9& 33\\
2~(15th)& 0.99&  --193.9--+193.9 & 9.7& 19.4& 11& 53\\
\hline
\end{tabular}}
\medskip
$^a$ Wavelength sampling for $-70$~pm $< \lambda < 70$~pm (core);
$^b$ wavelength sampling for $\lambda > 70$~pm, $\lambda < -70$~pm (wings).
\end{table}