\begin{table}%T6 \caption{\label{peaks}List of observed peaks in the redshift distribution of the reference master catalog. } \small%\centering \par \begin{tabular}{c c c c c} \hline \hline\noalign{\smallskip} $\langle z\rangle$ & $\sigma_V$~[km~s$^{-1}$] & $z_{\rm min}-z_{\rm max}$ & $N$ & XID \\ (1) & (2) & (3) & (4) & (5) \\ \hline 0.126 & 906 & $0.119{-}0.133$ & 73 & -- \\ 0.215 & 443 & $0.211{-}0.218$ & 61 & -- \\ 0.338 & 1724 & $0.322{-}0.353$ & 76 & -- \\ 0.530 & 2190 & $0.508{-}0.552$ & 193 & -- \\ 0.672 & 1758 & $0.653{-}0.692$ & 306 & 645 \\ 0.735 & 565 & $0.728{-}0.742$ & 257 & 566, 594 \\ 0.973 & 2936 & $0.935{-}1.012$ & 181 & 249 \\ 1.039 & 859 & $1.028{-}1.051$ & 110 & -- \\ 1.095 & 1536 & $1.074{-}1.117$ & 129 & -- \\ 1.221 & 391 & $1.215{-}1.227$ & 65 & -- \\ 1.296 & 261 & $1.292{-}1.300$ & 35 & -- \\ 1.611 & 497 & $1.602{-}1.620$ & 36 & -- \\ 2.318 & 2102 & $2.272{-}2.365$ & 108 & -- \\ 2.566 & 1435 & $2.532{-}2.601$ & 72 & -- \\ 2.811 & 575 & $2.796{-}2.825$ & 23 & -- \\ 3.471 & 984 & $3.442{-}3.501$ & 29 & -- \\ 3.702 & 360 & $3.691{-}3.714$ & 11 & -- \\ \hline \end{tabular} \tablefoot{The columns list: (1) the average $\langle z\rangle$ of each peak; (2)~the velocity dispersion $\sigma_V$; (3)~the redshift range corresponding to $\pm${}$2\sigma_V$, selected for the analysis of the spatial distribution (see Figs.~\ref{654},~\ref{736}, and~\ref{280}); (4)~the number of galaxies in the selected redshift interval; and (5) the identification numbers of extended X-ray sources \citep[from ][]{gia02} associated with the peak.} \end{table}