\begin{table}%t2 %\centering \par \caption{\label{eta_mb}Energies of the upper levels, $E_{\rm up}$, main-beam efficiencies, $\eta_{{\rm mb}}$, and main-beam FWHM:s, $\theta_{{\rm mb}}$, at the frequencies of the observed CO and SiO lines.} \small \begin{tabular}{cccccc} \hline\hline Transition &Frequency &$E_{\rm up}$ & $\eta_{\rm mb}$ & $\theta_{\rm mb}$ & Telescope\\ & [GHz] & [K] && [''] & \\ \hline ${\rm CO}(J=1\rightarrow0)$ & 115.271 & 5.5 & 0.43 & 33 & {OSO} \\ ${\rm CO}(J=1\rightarrow0)$ &115.271 & 5.5 & 0.74 & 22 & {IRAM} \\ ${\rm CO}(J=2\rightarrow1)$ & 230.538 & 16.6 & 0.52 & 11 & {IRAM} \\ ${\rm CO}(J=3\rightarrow2)$ & 345.796 & 33.2 & 0.56 & 14 & {JCMT} \\ ${\rm CO}(J=3\rightarrow2)$ & 345.796 & 33.2 & 0.70 & 18 & {APEX} \\ ${\rm SiO}(J=2\rightarrow1)$ &86.847 & 6.3 & 0.65 & 44 & {OSO} \\ ${\rm SiO}(J=2\rightarrow1)$ & 86.847 & 6.3 & 0.78 & 29 & {IRAM} \\ ${\rm SiO}(J=5\rightarrow4)$ & 217.105 & 31.3 & 0.57 & 12 & {IRAM} \\ ${\rm SiO}(J=6\rightarrow5)$ & 260.518 & 43.8 & 0.69 & 21 & {JCMT} \\ ${\rm SiO}(J=8\rightarrow7)$ & 347.331 & 75.0 & 0.63 & 14 & {JCMT} \\ ${\rm SiO}(J=8\rightarrow7)$ & 347.331 & 75.0 & 0.70 & 18 & {APEX} \\ \hline \end{tabular} \end{table}