\begin{table}%t5 \caption{\label{tab6}Emission line intensities in stacked RGS spectra of oxygen luminosity selected, low counts CIELO sources.} %\centerline {\begin{tabular}{lcc} \hline \hline Transition & Low oxygen-L$^a$ & High oxygen-L$^a$ \\ \hline Fe {\sc xviii} 3$^{\rm s}$2$^{\rm p}$ & $0.47 \pm 0.26$ & $<$0.14 \\ Fe {\sc xvii} 3$^{\rm d}$2$^{\rm s}$ & $0.67 \pm 0.34$ & $<$0.20 \\ Fe {\sc xvii} 3$^{\rm s}$2$^{\rm p}$ & $1.00 \pm 0.50$ & $<$0.23 \\ Fe {\sc xxi} 3$^{\rm d}$2$^{\rm p}$ & $0.76 \pm 0.43$ & $<$0.95 \\ Ne {\sc ix} He-$\alpha$ (r) & $0.57 \pm 0.32$ & $0.17 \pm 0.10$ \\ Ne {\sc ix} He-$\alpha$ (i) & $<$0.20 & $<$0.09 \\ Ne {\sc ix} He-$\alpha$ (f) & $0.24 \pm 0.22$ & $0.21 \pm 0.10$ \\ N {\sc vi} He-$\alpha$ (r) & $<$0.85 & $<$0.30 \\ N {\sc vi} He-$\alpha$ (i) & $0.70 \pm 0.47$ & $0.20 \pm 0.17$ \\ N {\sc vi} He-$\alpha$ (f) & $0.93 \pm 0.56$ & $0.35 \pm 0.18$ \\ N {\sc vii} Ly-$\alpha$ & $0.72 \pm 0.44$ & $<$0.17 \\ O {\sc viii} Ly-$\alpha$ & $1.25 \pm 0.58$ & $0.48 \pm 0.14$ \\ O {\sc viii} Ly-$\beta$ & $0.44 \pm 0.26$ & $0.48 \pm 0.14$ \\ O {\sc vii} He-$\alpha$ (r) & $0.84 \pm 0.50$ & $0.52 \pm 0.20$ \\ O {\sc vii} He-$\alpha$ (i) & $<$0.54 & $<$0.24 \\ O {\sc vii} He-$\alpha$ (f) & $1.00 \pm 0.41$ & $1.00 \pm 0.20$ \\ \hline \end{tabular}}\medskip \par $^a$ Normalised to the O{\sc vii} He-$\alpha$ (f). \par \end{table}