\begin{table}%t1
%\centering
\par
 {\footnotesize
\caption{\label{tab:sample}Overview of the sample \citep[see][]{schwope}.}
\begin{tabular}{c c c c c c c l }     
\hline\hline
RBS & $\alpha$ (J2000) & $\delta$ (J2000) &  &  & & $n_{\rm H}$ & Alternative   \\
number & [h m s] & [d m s] & $z$ & 1\myarcsec0~=~[kpc] & $L_{\rm X}$ & [$10^{22}~{\rm e}^-$/cm$^2$] & name\\
\hline
   RBS-0172 & 01 15 48.8 & --56 55 29 & 0.272 & 4.16 & 44.8 & 3.39 & APMUKS(BJ) B011348.12-571116.8\\
   RBS-0238 & 01 45 11.9 & --60 33 45 & 0.1795 & 3.03 & 44.6 & 3.36 & \\
   RBS-0312 & 02 24 36.4 & --24 33 44 & 0.305 & 4.51 & 44.8 & 1.69 & \\
   RBS-0325 & 02 32 16.4 & --44 20 48 & 0.282 & 4.27 & 44.8 & 2.61 & \\
   RBS-0380 & 03 01 07.5 & --47 06 25 & 0.515 & 6.20 & 45.3 & 2.23 & \\
   RBS-0381 & 03 01 38.5 & +01 55 16 & 0.1690 & 2.88 & 44.5 & 7.7 & ZwCl 0258.9+0142, RHS 18, 4C +01.06 \\
   RBS-0436 & 03 31 06 & --21 00 34 & 0.189 & 3.16 & 44.6 & 2.47 & \\
   RBS-0464 & 03 42 54.2 & --37 07 39 & 0.201 & 3.31 & 44.5  & 1.64& \\
   RBS-0651 & 05 28 15.1 & --29 43 03 & 0.157 & 2.72 & 44.2  & 1.83 & [BCT2000] J052815.92-294300.8 \\
   RBS-0653 & 05 28 52.7& --39 28 18 & 0.286 & 4.31 & 44.9 & 2.1 & NVSS J052853-392815 \\
   RBS-0745 & 09 09 00.4 & +10 59 35 & 0.1600 & 2.76 & 44.5 & 3.91 & MS 0906.3+1111\\
   RBS-0864 & 10 23 39.6 & +04 11 10 & 0.2906 & 4.36 & 45.3  & 2.87 & ZwCl 1021.0+0426, Z3146 \\
   RBS-1015 & 11 40 23.54 & +15 28 10 & 0.24 & 3.79 & 44.9  & 2.65 & \\
   RBS-1029 & 11 45 35.1 & --03 40 02 & 0.1683 & 2.87 & 44.6  & 2.49 & SDSS J114535.10-034001.6\\
   RBS-1267 & 13 26 17.7 & 12 29 58 & 0.2034 & 3.34 & 44.7 & 1.95 & [VCV2001] J132617.6+123000\\
   RBS-1316 & 13 47 32 & --11 45 42 & 0.451 & 5.77 & 45.5 & 4.92 &  RX J1347.5-1145, LCDCS 0829\\
   RBS-1460 & 15 04 07.6 & --02 48 17 & 0.2169 & 3.51 & 45.2  & 5.98 & LCRS B150131.5-023636, QUEST J1504-0248\\
   RBS-1691 & 20 41 50.1 & --37 33 39 & 0.100 & 1.84 & 44.2 & 3.61 & \\
   RBS-1712 & 21 02 04.4 & --24 33 58 & 0.1880 & 3.14 & 44.6  & 5.33 & EXO 2059-247 ID\\
   RBS-1748 & 21 29 39.7 & +00 05 18 & 0.233 & 3.71 & 45.0  & 4.22 & \\
   RBS-1842 & 22 16 56.7 & --17 25 27 & 0.1360 & 2.41 & 44.2  & 2.28 & [BCT2000] J221657.46-172528.3\\
\par
\hline
\end{tabular}
}
\end{table}