\begin{table}%t1 \caption{\label{tab-obs}HIFI observations of $\chi$ Cyg.} %\centerline {\small \begin{tabular}{llrrr} \hline \hline\noalign{\smallskip} Molecule & Transition & $\nu$ (GHz) & $E_{\rm up}$ (K)& $I$\tablefootmark{a} (K km s$^{-1}$) \\ \hline CO & $J=6$--5 & 691.473 & 116 & 15.3 \\ CO & $J=10$--9 & 1151.985 & 304 & 13.6 \\ CO & $J=16$--15 & 1841.346 & 752 & 13.5 \\ o-H$_{2}$O & 1$_{10} {-} 1_{01}$ & 556.936 & 61 & 3.0 \\ p-H$_{2}$O & 2$_{11} {-} 2_{02}$ & 752.033 & 137 & 4.2 \\ p-H$_{2}$O & 2$_{02} {-} 1_{11}$ & 987.927 & 101 & 7.3 \\ p-H$_{2}$O & 1$_{11} {-} 0_{00}$ & 1113.343 & 53 & 8.0 \\ o-H$_{2}$O & 3$_{12} {-} 2_{21}$ & 1153.127 & 249 & 7.5 \\ o-H$_{2}$O & 3$_{21} {-} 3_{12}$ & 1162.912 & 305 & 1.5 \\ o-H$_{2}$O & 3$_{03} {-} 2_{12}$ & 1716.770 & 197 & 18.1 \\ \hline \end{tabular}} \tablefoot{\tablefoottext{a}{The absolute calibration accuracy is between 10\% to 30\% (see text).}} \end{table}