\begin{table}%t3[htbp]
%\centering
\par
\caption{Central positions, redshifts and velocity dispersions of
the known
  clusters in the A~901 field \citep{taylor2004}.}
\begin{tabular}{lcccc}
\hline\hline \noalign{\smallskip}
 & $\alpha_{{\rm J2000}}$ & $\delta_{{\rm J2000}}$ & $z$ & $\sigma_v$ [km~s$^{-1}$]\\
\noalign{\smallskip} \hline \noalign{\smallskip} \rule[-2mm]{0mm}{0mm}A901a &
$09^{{\rm h}}56^{{\rm m}}26.4^{{\rm s}}$
& $-09^{{\rm h}}57^{{\rm m}}21.7^{{\rm s}}$ & $0.16$ & $680^{+25}_{-90}$ \\
\rule[-2mm]{0mm}{0mm}A901b &
$09^{{\rm h}}55^{{\rm m}}57.4^{{\rm s}}$
& $-09^{{\rm h}}59^{{\rm m}}02.7^{{\rm s}}$ & $0.16$ & $600^{+40}_{-85}$\\
\rule[-2mm]{0mm}{0mm}A902 &
$09^{{\rm h}}56^{{\rm m}}33.6^{{\rm s}}$
& $-10^{{\rm h}}09^{{\rm m}}13.1^{{\rm s}}$ & $0.16$ & $470^{+100}_{-280}$\\
\rule[-2mm]{0mm}{0mm}CBI &
$09^{{\rm h}}56^{{\rm m}}39.6^{{\rm s}}$
& $-10^{{\rm h}}10^{{\rm m}}21.6^{{\rm s}}$ & $0.48$ & $730^{+160}_{-340}$\\\hline
\end{tabular}
\label{tab:cluster_data}
\end{table}