\begin{table}%t3 \caption{\label{tab3}Mrk~509 absorption line parameters (rest-frame energies).} %\centerline {\small \begin{tabular}{c c c c c c c c} \hline\hline\noalign{\smallskip} N & $E^a$ & $EW^a$ & $\Delta\chi^2$ & F-test & MC$^b$ & Id & $v/c$\\ obs. & (keV) & (eV) & & & & (FeXXVI)& \\ \hline\noalign{\smallskip} 1 & $8.29\pm0.05$ & $-32\pm20$ & 9.6 & $\sim$99\% & 95\% & K$\alpha$&0.172~$\pm$~0.005\\ & $9.74\pm0.09$ & $\rm -59^{+18}_{-22}$ & 8 & $\sim$98.5\% & 87.5\% & K$\beta$ & 0.162~$\pm$~0.009 \\ 2 & $\equiv$8.29$^c$ & $\gsimeq$$-23$ & $\dots$ & $\dots$ & $\dots$ \\ & $\equiv$9.74$^c$ & $\gsimeq$$-32$ & $\dots$ & $\dots$ & $\dots$ \\ 4 & $8.03\pm0.03$& $-20\pm10$ & 16.5 & $\gsimeq$99.9\% & 99.8\% &K$\alpha$&0.141~$\pm$~0.003\\ & $\equiv$ 9.74$^c$ & $\gsimeq$$-17$ & \dots & \dots & \dots\\ 5 & $\equiv$8.29$^c$ & $\gsimeq$$-14$ & $\dots$ & $\dots$ & $\dots$ \\ & $\equiv$9.74$^c$ & $\gsimeq$$-17$ & $\dots$ & $\dots$ & $\dots$ \\ 6 & $8.50\pm0.05$ & $-20\pm12$ & 10.2 & $\sim$99.5\% & 95.5\% &K$\alpha$&0.196~$\pm$~0.005\\ & $\rm 9.8^{+0.1}_{-0.2}$ & $\rm -34^{+26}_{-29}$ & 7 & $\sim$98\% & 78\% & K$\beta$ &$\rm 0.17^{+0.02}_{-0.01}$\\[1mm] \hline \end{tabular}} \par \medskip $^a$~Rest-frame energy. Errors are quoted at the 90{\%} and 68{\%} confidence for the first and second lines, respectively. $^b$~Significance calculated through Monte Carlo simulations. $^c$~Values frozen at the best-fit values obtained during obs.~1. \end{table}