\begin{table}%t1
\caption{\label{tab1}List of the relaxed clusters analyzed in this work.}
%\centerline
 {\begin{tabular} {cccc} 
\hline\hline
Cluster   & $z$ &    kpc/$\arcsec$     & $D_{\rm L}$\\
          &   &                 & Mpc  \\
\hline
A1068      &   0.1375    & 2.40 & 641.45  \\
A1413      &   0.1427    & 2.48 & 667.98  \\
A1650      &   0.0843    & 1.56 & 379.24  \\
A1835      &   0.2532    & 3.91 & 1267.62 \\
A2029      &   0.0765    & 1.43 & 342.24  \\
Ophiuchus  &   0.028     & 0.55 & 120.84  \\ 
\hline
\end{tabular}}
\par
\smallskip
{Column 1: Cluster Name; Col.~2: Redshift;} 
{Col.~3: Angular to linear conversion;} 
{Col.~4: Luminosity distance.} 
\end{table}