\begin{table}%t2 \par \caption{\label{tab:obs}\label{tab2}Rms noise levels and naturally-weighted beam sizes of the final maps.} \small%\centering \par \begin{tabular}{lcccccccc} \hline \hline\noalign{\smallskip} {Source} & \multicolumn{2}{c}{230~GHz} & \multicolumn{2}{c}{230~GHz combined\tablefootmark{1}} & \multicolumn{2}{c}{$^{12}$CO(2--1)} & \multicolumn{2}{c}{107~GHz} \\ {} & {{\it HPBW}} & {rms} & {~~{\it HPBW}} & {~~rms} & {~~{\it HPBW}} & {rms~~} & {~~{\it HPBW}} & {rms~~} \\ {} & {} & {(mJy/beam)} & {} & {(mJy/beam)} & {} & {(mJy/beam)} & {} & {(mJy/beam)} \\ \hline\noalign{\smallskip} {L1448-C} & $0.48\arcsec \times 0.27\arcsec$ & 0.9 & $1.68\arcsec \times 1.39\arcsec$ & 2.8 & 0.48$\arcsec \times 0.27\arcsec$ & 10 & 4.08$\arcsec \times 3.27\arcsec$ & 10 \\ {NGC~1333-IRS2A}& 0.49$\arcsec \times 0.32\arcsec$ & 1.16 & -- & -- & 0.49$\arcsec \times 0.32\arcsec$ & 20 & -- & -- \\ {IRAM~04191}& 0.56$\arcsec \times 0.31\arcsec$ & 0.37 & 1.37$\arcsec \times 0.82\arcsec$ & 0.31 & 0.56$\arcsec \times 0.31\arcsec$ & 10 & -- & -- \\ {L1527}& 0.48$\arcsec \times 0.28\arcsec$ & 1.2 & 0.88$\arcsec \times 0.79\arcsec$ & 2.0 & 0.48$\arcsec \times 0.28\arcsec$ & 20 & -- & -- \\ {L1521-F} & 0.49$\arcsec \times 0.27\arcsec$ & 0.12 & -- & -- & 0.48$\arcsec \times 0.27\arcsec$ & 8 & -- & -- \\ \hline \end{tabular} \tablefoot{\tablefoottext{1}{L1448-C and L1527: combination of 230~GHz data from project R068 with 218~GHz data from project G080. IRAM~04191: combination of 230~GHz data from project R068 with 227~GHz data from Belloche et al. (2002).}} \end{table}