\begin{table}%Ta7
\caption{\label{tab:omdata}Optical properties of the AGN of the present catalog (from the Optical Monitor data). The data
refers to the magnitude averaged over the whole observation. 
Columns: 
(1) Source name; 
(2) $V$ magnitude [$543$~nm]; 
(3) $B$ magnitude [$450$~nm]; 
(4) $U$ magnitude [$344$~nm]; 
(5) {\it UVW1}~magnitude [$291$~nm]; 
(6) {\it UVM2} magnitude [$231$~nm];
(7) {\it UVW2} magnitude [$212$~nm];
The uncertainties in the parameter estimates are at the $1\sigma$~level and also include systematics.}
\small%\centerline
{
\begin{tabular}{lcccccc}
\hline\hline
Name          & $V$                 & $B$                 & $U$               & {\it UVW1}              & {\it UVM2}            & {\it UVW2}\\
(1)          & (2)               & (3)               & (4)             & (5)                & (6)             & (7) \\
\hline
$0219+428$    & {}                & {}                & {}              & $15.1\pm 0.1$    &  {}              & {}\\
AO~$0235+164$ & {}            & {}                & {}                  & $17.0\pm 0.1$    & {}              & {}\\
PKS~$0521-365$ & {}                & {}                & {}              & {}                 & {}              & {}\\
S5~$0716+714$ & $13.4\pm 0.1$   & {}                & $12.9\pm 0.1$ & $12.8\pm 0.1$    & $12.8\pm 0.1$   & {}\\
S5~$0836+710$ & $16.6\pm 0.1$   & {}                & $15.9\pm 0.1$ & $16.1\pm 0.1$    & {}              & $16.5\pm 0.1$ \\
Mkn~$421$ & {}                & {}                & {}              & {}                 & {}              & {}\\
{}           & {}                & {}                & {}              & {}                 & {}              & {}\\
PKS~$1127-145$ & {}            & {}                & {}              & $15.7\pm 0.1$    & $15.7\pm 0.1$ & $15.9\pm 0.1$ \\
ON~$231$ & $14.6\pm 0.1$   & $15.0\pm 0.1$   & $14.2\pm 0.1$ & {}                 & {}              & {} \\
3C~$273$ & $12.6\pm 0.1$   & $12.9\pm 0.1$   & $11.8\pm 0.1$ & $11.5\pm 0.1$    & $11.3\pm 0.1$ & $11.3\pm 0.1$ \\
{}           & $12.7\pm 0.1$   & $12.9\pm 0.1$   & $11.7\pm 0.1$ & {}                 & {}              & {} \\
{}           & {}                & {}                & {}              & $11.5\pm 0.1$    & $11.3\pm 0.1$ & $11.3\pm 0.1$\\
{}           & $12.7\pm 0.1$   & $12.9\pm 0.1$   & $11.8\pm 0.1$ & $11.5\pm 0.1$    & $11.3\pm 0.1$ & $11.3\pm 0.1$ \\
{}           & {}                & {}                & {}              & $11.3\pm 0.1$    & $11.1\pm 0.1$ & $11.1\pm 0.1$ \\
{}           & {}                & {}                & {}              & {}                 & {}              & {} \\
{}           & {}                & {}                & {}              & $11.4\pm 0.1$    & $11.3\pm 0.1$ & {} \\
{}           & {}                & {}                & {}              & {}                 & {}              & {} \\
{}           & $12.7\pm 0.1$   & $13.0\pm 0.1$   & $11.8\pm 0.1$ & $11.6\pm 0.1$    & $11.5\pm 0.1$ & $11.4\pm 0.1$ \\
Cen~A$^{*}$ & {}                & {}                & {}              & {}                 & {}              & {}  \\
PKS~$1334-127$ & {}            & {}                & {}              & $16.3\pm 0.1$    & $16.2\pm 0.1$  & {} \\
PKS~$1406-076$ & {}                & $19.5\pm 0.2$     & {}              & $18.6\pm 0.1$    & {}              & $19.7\pm 0.1$ \\
{}           & {}                & {}                & {}              & $19.4\pm 0.4$      & {}              & {} \\
NGC~$6251$ & {}                & $15.6\pm 0.1$   & $16.4\pm 0.1$  & $16.6\pm 0.1$   & {}              & {}  \\
PKS~$1830-211^{*}$ & {}                & {}                & {}              & {}                 & {}              & {} \\
{}           & {}                & {}                & {}              & {}                 & {}              & {} \\
PKS~$2155-304$ & {}                & {}                & {}              & {}                 & {}              & $12.5\pm 0.1$ \\
{}           & {}                & {}                & {}              & {}                 & {}                & $12.1\pm 0.1$ \\
{}           & {}                & {}                & {}              & {}                 & {}                & $12.2\pm 0.1$ \\
{}           & $13.2\pm 0.1$     & $13.4\pm 0.1$     & $12.4\pm 0.1$ & {}                 & {}              & {}           \\
{}           & $13.9\pm 0.1$     & $14.2\pm 0.1$     & $13.2\pm 0.1$ & {}               & {}              & $12.8\pm 0.1$ \\
{}           & $13.8\pm 0.1$ & $14.2\pm 0.1$   &  {}              & $13.1\pm 0.1$  & $12.9\pm 0.1$ & $12.9\pm 0.1$ \\
{}           & {}                & {}                & $12.9\pm 0.1$ & $12.7\pm 0.1$  & $12.6\pm 0.1$ & {} \\
{}           & $13.5\pm 0.1$ & {}                & $13.2\pm 0.1$ & {}                 & {}              & {}           \\
{}           & {}                & $14.3\pm 0.1$ & {}              & $12.7\pm 0.1$  & $12.6\pm 0.1$ & $12.6\pm 0.1$  \\
\hline
\end{tabular}}
\smallskip
$^{*}$ Source beyond the capabilities of OM: too faint or too bright.
\end{table}