\begin{table}%t1
\caption{\label{Table:sample}Parameters of the clusters' sample.}
%\centerline
 {
\par
\hspace*{-1mm}\begin{tabular}{lcccccr}
\hline\hline
\multicolumn{1}{c}{Name} &
\multicolumn{1}{c}{RA}  &
\multicolumn{1}{c}{Dec}  &
\multicolumn{1}{c}{Age} &
\multicolumn{1}{c}{[Fe/H]} &
\multicolumn{1}{c}{$\Delta K$} &
\multicolumn{1}{c}{Ref.}\\
%\hline
& hh:mm:ss
& $^{\circ}$~:~$^{\prime}$~:~$^{\prime\prime}$
& [Gyr]
&
& [mag]
& \\
\hline
NGC~188  & 00:47:28 &   +22.384 & 6.0 &   +0.01 $\pm$ 0.08~~ & 4.0 $\pm$ 0.15 &  1\\
NGC~752  & 01:57:41 & $-$23.254 & 1.6 & $-$0.16 $\pm$ 0.10~~ & 2.7 $\pm$ 0.20 &  2\\
NGC~2420~& 07:38:23 &   +19.634 & 2.1 & $-$0.26 $\pm$ 0.07~~ & 3.3 $\pm$ 0.20 &  3\\
NGC~2477 & 07:52:10 & $-$05.850 & 0.8 &   +0.07 $\pm$ 0.03~~ & 1.9 $\pm$ 0.25 &  4\\
NGC~2506 & 08:00:01 &   +09.935 & 1.9 & $-$0.37 $\pm$ 0.02~~ & 3.1 $\pm$ 0.25 &  5\\
NGC~2509 & 08:00:48 &   +05.820 & 1.2 &   +0.00 $\pm$ 0.10~~ & 2.5 $\pm$ 0.20 &  6\\
M~67     & 08:51:18 &   +31.896 & 4.0 &   +0.00 $\pm$ 0.01~~ & 3.8 $\pm$ 0.10 &  7\\
NGC~3680 & 11:25:38 &   +16.918 & 1.8 & $-$0.16 $\pm$ 0.03~~ & 2.9 $\pm$ 0.15 &  8\\
NGC~6134 & 16:27:46 & $-$00.200 & 1.0 &   +0.18 $\pm$ 0.10~~ & 2.0 $\pm$ 0.15 &  9\\
NGC~6253 & 16:59:05 & $-$06.260 & 3.0 &   +0.36 $\pm$ 0.07~~ & 3.7 $\pm$ 0.15 & 10\\
IC~4651  & 17:24:49 & $-$07.907 & 1.1 & $-$0.11 $\pm$ 0.01~~ & 2.1 $\pm$ 0.20 & 11\\
NGC~6819 & 19:41:18 &   +08.481 & 2.5 &   +0.09 $\pm$ 0.03~~ & 3.4 $\pm$ 0.25 & 12\\
NGC~6939 & 20:31:30 &   +12.304 & 2.2 &   +0.02 $\pm$ 0.05~~ & 3.2 $\pm$ 0.15 & 13\\
NGC~7789 & 23:57:24 & $-$05.385 & 1.4 & $-$0.10 $\pm$ 0.05~~ & 2.4 $\pm$ 0.20 & 14\\
\hline
\end{tabular}}
\medskip
\par
The last column gives a reference to the literature source of the adopted cluster age and metallicity.\\
 1)~Fornal et~al. (\cite{for07});
 2)~Anthony-Twarog \& Twarog (\cite{ant06b});
 3)~Anthony-Twarog et~al. (\cite{ant06a});
 4)~Kassis et~al. (\cite{kas97});
 5)~Marconi et~al. (\cite{mar97});
 6)~Carraro \& Costa (\cite{car07});
 7)~Sarajedini et~al. (\cite{sar09});
 8)~Anthony-Twarog \& Twarog (\cite{ant04});
 9)~Bruntt et~al. (\cite{bru99});
10)~Twarog et~al. (\cite{twa03});
11)~Meibon et~al. (\cite{mei02});
12)~Kalirai et~al. (\cite{kal01});
13)~Andreuzzi et~al. (\cite{and04});
14)~Vallenari et~al. (\cite{val00}).
\end{table}