\begin{table}%t3 \par \caption{\label{tbl:plines}Parameters of the strongest emission lines.} %\centerline { \begin{tabular}{l c c c c c c c c c c c c} \hline \hline \noalign{\smallskip} & $\lambda_{\rm C}$ & EW & \multicolumn{2}{c}{Flux\tablefootmark{a}}\\ & (\AA) & (m\AA) & \multicolumn{2}{c}{($\times$10$^{-4}$)}\\ \hline\\[-2.2ex] Ne~X~Ly$\alpha$\tablefootmark{c} & 12.131[11] & 125[18] & 2.15[31] & (1.26~$\pm$~0.16) \\ [0.2ex] O~VIII~Ly$\beta$\tablefootmark{c} & 15.997[41] & 40[14] & 0.55[20] & (0.31~$\pm$~0.16) \\ [0.2ex] O~VIII~Ly$\alpha$\tablefootmark{c} & 18.9796[49] & 360[28] & 3.93[31] & (1.71~$\pm$~0.26) \\ [0.2ex] O~VII~$r$$^b$ & 21.60[90] & 163[19] & 1.72[20] & (0.77~$\pm$~0.28) \\ [0.2ex] O~VII~$i$$^b$ & 21.78[92] & 149[19] & 1.58[20] & (0.79~$\pm$~0.40) \\ [0.2ex] O~VII~$f$$^b$ & 22.097\tablefootmark{d} & $<$32 & $<$0.3 & (0.13~$\pm$~0.16) \\ [0.2ex] N~VII~Ly$\alpha$\tablefootmark{c} & 24.79[99] & 296[17] & 2.76[16] & (0.61$\pm$~0.03) \\ [0.2ex] N~VI~$r$\tablefootmark{c} & 28.81[90] & $<$230 & $<$2 & ... \\ [0.2ex] N~VI~$i$\tablefootmark{c} & 29.09[95] & $<$169 & $<$1.4 & ... \\ [0.2ex] N~VI~$f$\tablefootmark{c} & 29.531\tablefootmark{d} & $<$10 & $<$0.08 & ... \\ [0.2ex] C~VI~Ly$\alpha$\tablefootmark{d} & 33.736[64] & 201[29] & 1.37[20] & ... \\ [0.2ex] \hline \end{tabular} } \tablefoot { \tablefoottext{a}{Total flux in line, in units of photons~cm$^{-2}$~s$^{-1}$; in parenthesis are shown the values derived by \citet{Smith04} from Chandra.} \tablefoottext{b}{From RGS1.} \tablefoottext{c}{From RGS2.} \tablefoottext{d}{Frozen parameter. Quoted errors are at~90\% confidence level.}} \end{table}