All Figures

$\begin{figure} \par\includegraphics[width=8cm,clip]{4476fig1.ps}\end{figure}$ Figure 1: Rotational diagrams for deuterated formaldehyde for the seven studied sources, assuming 10'' for the source size. Error bars correspond to the error bars on the flux as stated in Tables 6-8.
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In the text

$\begin{figure} \par\includegraphics[width=8.2cm,clip]{4476fig2.ps} \end{figure}$ Figure 2: Rotational diagrams for deuterated methanol in IRAS4A, IRAS4B and IRAS2 (for the sake of clarity the curves for CH₃OD and CHD₂OH have been translated by -2 and -7 along the y-axis). Error bars correspond to the error bars on the flux as stated in Tables 6 and 7. Solid lines (CH₂DOH) correspond to fits to the data, with two free parameters ( $T_{\rm rot}$ and $N_{\rm tot}$ ). Dashed lines correspond to fits with only $N_{\rm tot}$ as a free parameter, and $T_{\rm rot}$ set to the value derived for CH₂DOH (cf. text).
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In the text

$\begin{figure} \par\includegraphics[width=12cm,clip]{4476fig3.ps} \end{figure}$ Figure 3: Fractionation of formaldehyde and methanol as a function of bolometric luminosity and the $L_{\rm smm}$ / $L_{\rm bol}$ (from André et al. 2000).
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In the text

$\begin{figure} \par\includegraphics[width=7.8cm,clip]{4476fig4.ps} \end{figure}$ Figure 4: Doubly-deuteration of formaldehyde versus CO depletion. Class 0 sources (this work) appear as diamonds and prestellar cores (Bacmann et al. 2002) as triangles. The reversed triangle is the upper limit for L1157mm (this work).
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In the text

$\begin{figure} \par\includegraphics[width=13.54cm,clip]{4476fig5.ps} \end{figure}$ Figure 5: Comparison between the observed fractionations (triangles are for formaldehedyde species, whereas diamonds are for methanol species) towards the seven sources in our sample (solid lines) and the predictions of the grain model (dashed lines, Stantcheva & Herbst 2003). IRAS 16293 has been added in the last panel for comparison.
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In the text

$\begin{figure} \par\includegraphics[width=7.8cm,clip]{4476fig6.ps} \end{figure}$ Figure 6: Repartition function for the CH₂DOH/CH₃OH ratio (solid line). Overlaid in a dash-dot line is the repartition function computed assuming that the ratio is Gaussian, with a width computed by the standard error propagation. Vertical lines delimitate the 90% confidence intervals for the two distributions.
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In the text

$\begin{figure} \par\includegraphics[angle=-90,width=16.5cm,clip]{4476fig7.eps} %\end{figure}$ Figure 7: HDCO lines for IRAS4a, IRAS4b, and IRAS2.
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In the text

$\begin{figure} \par\includegraphics[width=16.5cm,clip]{4476fig8.eps} \end{figure}$ Figure 8: HDCO lines for L1448N, L1448mm, and L1157mm.
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In the text

$\begin{figure} \par\includegraphics[angle=-90,width=16.5cm,clip]{4476fig9.eps} \end{figure}$ Figure 9: D₂CO lines for IRAS4a, IRAS4b, and IRAS2.
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In the text

$\begin{figure} \par\includegraphics[angle=-90,width=16.5cm,clip]{4476fig10.eps} \end{figure}$ Figure 10: D₂CO lines for L1448N, L1448mm, and L1157mm.
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In the text

$\begin{figure} \par\includegraphics[angle=-90,width=16.5cm,clip]{4476fig11.eps}\end{figure}$ Figure 11: CH₂DOH lines for IRAS4a, IRAS4b, and IRAS2.
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In the text

$\begin{figure} \par\includegraphics[angle=-90,width=16.5cm,clip]{4476fig12.eps}\end{figure}$ Figure 12: CH₂DOH lines for IRAS4a, IRAS4b, and IRAS2.
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In the text

$\begin{figure} \par\includegraphics[width=8cm,clip]{4476fig1.ps}\end{figure}$	Figure 1: Rotational diagrams for deuterated formaldehyde for the seven studied sources, assuming 10'' for the source size. Error bars correspond to the error bars on the flux as stated in Tables 6-8.
Open with DEXTER

$\begin{figure} \par\includegraphics[width=12cm,clip]{4476fig3.ps} \end{figure}$	Figure 3: Fractionation of formaldehyde and methanol as a function of bolometric luminosity and the $L_{\rm smm}$ / $L_{\rm bol}$ (from André et al. 2000).
Open with DEXTER

$\begin{figure} \par\includegraphics[width=7.8cm,clip]{4476fig4.ps} \end{figure}$	Figure 4: Doubly-deuteration of formaldehyde versus CO depletion. Class 0 sources (this work) appear as diamonds and prestellar cores (Bacmann et al. 2002) as triangles. The reversed triangle is the upper limit for L1157mm (this work).
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$\begin{figure} \par\includegraphics[width=13.54cm,clip]{4476fig5.ps} \end{figure}$	Figure 5: Comparison between the observed fractionations (triangles are for formaldehedyde species, whereas diamonds are for methanol species) towards the seven sources in our sample (solid lines) and the predictions of the grain model (dashed lines, Stantcheva & Herbst 2003). IRAS 16293 has been added in the last panel for comparison.
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$\begin{figure} \par\includegraphics[width=7.8cm,clip]{4476fig6.ps} \end{figure}$	Figure 6: Repartition function for the CH₂DOH/CH₃OH ratio (solid line). Overlaid in a dash-dot line is the repartition function computed assuming that the ratio is Gaussian, with a width computed by the standard error propagation. Vertical lines delimitate the 90% confidence intervals for the two distributions.
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$\begin{figure} \par\includegraphics[angle=-90,width=16.5cm,clip]{4476fig7.eps} %\end{figure}$	Figure 7: HDCO lines for IRAS4a, IRAS4b, and IRAS2.
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$\begin{figure} \par\includegraphics[width=16.5cm,clip]{4476fig8.eps} \end{figure}$	Figure 8: HDCO lines for L1448N, L1448mm, and L1157mm.
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$\begin{figure} \par\includegraphics[angle=-90,width=16.5cm,clip]{4476fig9.eps} \end{figure}$	Figure 9: D₂CO lines for IRAS4a, IRAS4b, and IRAS2.
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$\begin{figure} \par\includegraphics[angle=-90,width=16.5cm,clip]{4476fig10.eps} \end{figure}$	Figure 10: D₂CO lines for L1448N, L1448mm, and L1157mm.
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$\begin{figure} \par\includegraphics[angle=-90,width=16.5cm,clip]{4476fig11.eps}\end{figure}$	Figure 11: CH₂DOH lines for IRAS4a, IRAS4b, and IRAS2.
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$\begin{figure} \par\includegraphics[angle=-90,width=16.5cm,clip]{4476fig12.eps}\end{figure}$	Figure 12: CH₂DOH lines for IRAS4a, IRAS4b, and IRAS2.
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