\begin{table}%t1 \caption{\label{table:clumps}Submillimetre clumps identified by the \texttt{clumpfind} algorithm in the IRDC G304.74.} \small %\centering \begin{tabular}{c c c c c c c c} \hline\hline \noalign{\smallskip} & \multicolumn{2}{c}{Peak position} & $S_{870}^{\rm peak}$\tablefootmark{a} & $S_{870}$\tablefootmark{a} & $\theta_{\rm s}$ & $R_{\rm eff}$\tablefootmark{b} & 1.2~mm clump No.\tablefootmark{c}\\ Name & $\alpha_{2000.0}$ [h:m:s] & $\delta_{2000.0}$ [$\degr$:$\arcmin$:$\arcsec$] & [Jy beam$^{-1}$] & [Jy] & [\arcsec] & [\arcsec] & (Beltr\'an et~al. 2006)\\ \hline SMM~1 & 13 06 20.5 & $-$61 30 15 & 0.46 & 2.0 & 36 & 36 &\\ SMM~2 & 13 06 26.9 & $-$61 29 39 & 0.30 & 1.0 & 38 & 28 &\\ SMM~3 & 13 06 35.8 & $-$61 28 53 & 0.50 & 3.4 & 45 & 42 & 1\\ SMM~4 & 13 06 44.7 & $-$61 28 35 & 0.66 & 4.1 & 38 & 38 & 3\\ IRAS~13037-6112 & 13 06 49.8 & $-$61 28 07 & 0.47 & 1.6 & 24 & 26 & 2\\ SMM~5 & 13 06 49.9 & $-$61 26 55 & 0.19 & 0.7 & 28 & 26&\\ SMM~6 & 13 06 51.1 & $-$61 27 49 & 0.46 & 1.8 & 27 & 30 & 4\\ SMM~7 & 13 07 02.6 & $-$61 26 18 & 0.26 & 0.9 & 24 & 30 & 8\\ IRAS~13039-6108 & 13 07 06.4 & $-$61 24 29 & 0.47 & 2.6 & 37 & 40 & 5\\ SMM~8 & 13 07 08.9 & $-$61 23 25 & 0.31 & 1.1 & 26 & 29 & \\ SMM~9 & 13 07 12.7 & $-$61 22 49 & 0.38 & 1.6 & 35 & 32 & 6\\ IRAS~13042-6105 & 13 07 20.3 & $-$61 21 45 & 0.21 & 0.8 & 28 & 27 & 7\\ \hline \end{tabular} \tablefoot{\tablefoottext{a}{The peak and total flux densities have estimated uncertainties of~$\sim$$20{-}50\%$, depending on the intensity of negative holes around the clump (see Sect.~2.1).}\\ \tablefoottext{b}{The effective radius, $R_{\rm eff}=\sqrt{A/\pi}$, where $A$ is the area assigned to the clump, i.e., area contained within a $2\sigma$ contour. The radius has not been deconvolved from the beam size.}\\ \tablefoottext{c}{Corresponding 1.2~mm clump in Beltr\'an et~al. (2006).}} \end{table}