\begin{table}%t1 \caption{\label{observations}Observation summary.} %\centerline { \small \begin{tabular}{lcccc} \hline\hline ID & XMM name & Obs.date & Exp. time & $S/N$ \\ & & & mn & \\ \hline %% 1703 & J005818.3-355548 & Oct. 23 2006 & 60 & 32.1 \\ 1774 & J005922.8-360933 & Oct. 26 2006 & 45 & 3.6 \\ 1778 & J005929.7-361113 & Oct. 28 2006 & 30 & 34.0 \\ 3654 & J022416.7-050323 & Oct. 29 2006 & 55 & -- \\ 3716 & J022456.2-050801 & Oct. 24 2006 & 40 & 2.5 \\ 3773 & J022536.4-050012 & Oct. 24 2006 & 30 & 84.7 \\ 3776 & J022537.8-050223 & Oct. 24 2006 & 40 & -- \\ 3777 & J022538.2-050806 & Oct. 25 2006 & 45 & 118.0 \\ 3778 & J022538.3-050423 & Oct. 29 2006 & 30 & 3.4 \\ 4009 & J023613.5-523036 & Oct. 23 2006 & 40 & 131.4 \\ 4298 & J030927.5-765223 & Oct. 28 2006 & 40 & 4.5 \\ 4379 & J031256.5-765039 & Oct. 29 2006 & 30 & 9.4 \\ 4481 & J031723.1-442056 & Oct. 28 2006 & 40 & 4.5 \\ 4736 & J031829.8-441140 & Oct. 29 2006 & 45 & 23.7 \\ 4765 & J031845.0-441042 & Oct. 23 2006 & 55 & 11.4 \\ 4927 & J033831.4-351421 & Oct. 25 2006 & 40 & 6.8 \\ 5570 & J043306.5-610760 & Oct. 24 2006 & 55 & 3.3 \\ 5663 & J043333.5-612427 & Oct. 24 2006 & 40 & 2.3 \\ 7355 & J055940.7-503218 & Oct. 24 2006 & 45 & 2.7 \\ 7400 & J060014.9-502230 & Oct. 24 2006 & 30 & -- \\ 12~281 & J201329.7-414737 & Oct. 27 2006 & 45 & 79.2 \\ 12~308 & J201345.0-563713 & Oct. 23 2006 & 30 & 2.0$^1$ \\ 13~137 & J213758.7-143611 & Oct. 23 2006 & 30 & 61.6 \\ 14~402 & J221726.0-082531 & Oct. 26 2006 & 30 & 2.6 \\ 14~541 & J222110.0-244749 & Oct. 28 2006 & 40 & -- \\ 14~608 & J222804.4-051751 & Oct. 29 2006 & 45 & -- \\ 15~022 & J225149.3-175225 & Oct. 23 2006 & 30 & 153.7 \\ 15~393 & J231421.6-424559 & Oct. 24 2006 & 40 & 4.0 \\ 15~584 & J231851.8-423114 & Oct. 25 2006 & 30 & 2.9 \\ 15~631 & J232454.9-120459 & Oct. 28 2006 & 45 & 1.9 \\ 15~867 & J235340.6-102420 & Oct. 23 2006 & 30 & 3.2 \\ 15~892 & J235405.7-101829 & Oct. 27 2006 & 45 & 1.3 \\ 15~926 & J235418.1-102013 & Oct. 28 2006 & 40 & 14.3 \\ 15~997 & J235629.1-343743 & Oct. 25 2006 & 30 & 2.0$^1$ \\ \hline \end{tabular}} \medskip $S/N$ of the Mg~I~b2 line. \end{table}