\begin{table}%t1
\caption{\label{Table:Observat}Observational diary: the data sources, number of points in each
curve, passband (effective central wavelength in nm), time interval in
Julian date minus~2~400~000, and year of observation. Vienna~$V$ and~$B$~refer to
the light curves obtained at Vienna Observatory, the Cereda~$B$ and~$V$~curves are by Cereda et~al. (\cite{Cereda1988}), $H_{{\rm p}}$ refers to the Hipparcos $H_{{\rm p}}$-band data centered~$\approx$500~nm and the Tycho \textit{BV}~data described and analyzed by~ZW03, DAO~indicates the Lu (\cite{Lu1993}) radial velocity curves, and Asiago stands
for the Asiago Observatory radial velocities from the Ca triplet region
(ZW03).}\small%\centering
\par
\begin{tabular}{cccccc}
\hline\hline
Data set & $n$ & $\lambda$ & $t_{\min }$ & $t_{\max }$ & year \\ 
\hline
Vienna $V$ & 1201 & 550 & 45359.3 & 45657.6 & 1983 \\ 
Vienna $B$ & 266 & 440 & 45662.3 & 45663.5 & 1983 \\ 
Cereda $B$ & 240 & 440 & 46775.5 & 46802.6 & 1986/87 \\ 
Cereda $V$ & 235 & 550 & 46775.5 & 46802.6 & 1986/87 \\ 
$H_{{\rm p}}$ & 61 & 500 & 47963.7 & 48486.5 & 1990--1993 \\ 
DAO $RV_{1+2}$ & 28 & 505 & 48187.0 & 48312.9 & 1991/92 \\ 
Asiago $RV_{1+2}$ & 34 & 861 & 51153.5 & 51626.4 & 1998--2000 \\ \hline
\end{tabular}
\end{table}