All Figures

$\begin{figure} \par\includegraphics[angle=270, width=14cm]{8054fig1.eps} \end{figure}$ Figure 1: Comparison between our approximation of $v_{\rm n}$ , $v_{\rm i}$ , $\Delta v$ , $T_{\rm n}$ , and $T_{\rm i}$ ( lower panels), and the MHD shock structure calculated as in Flower & Pineau des Forêts (2003, upper panels) for a shock with $v_{\rm s}=40$ km s^-1, n₀=10⁴ cm^-3 and $B_0=100~\mu$ G (Flower, private communication). Shock parameters are given in Table 3 and velocities are in the shock frame (see Appendix A for the definition of $v_{\rm n}$ and $v_{\rm i}$ ).
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In the text

$\begin{figure} \par\includegraphics[angle=270, width=7.5cm]{8054fig2.eps} % \end{figure}$ Figure 2: Comparison between the profiles of $v_{\rm n}$ , $v_{\rm i}$ and $T_{\rm n}$ derived with our approximation ( lower panel) and the MHD shock structure obtained by Kaufman & Neufeld (1996) for a shock with $v_{\rm s}=35$ km s^-1 and n₀=10⁸ km s^-1 ( upper panel). Parameters are given in Table 3 and velocities are in the shock frame.
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In the text

$\begin{figure} \par\includegraphics[angle=0, width=8.5cm]{8054fig3.eps} \end{figure}$ Figure 3: C-shock physical structure obtained with Eqs. (1), (3), and (4) for $v_{\rm s}=40$ km s^-1, n₀= 10⁵ cm^-3, and T₀=10 K. Velocities are in the frame co-moving with the preshock gas. The magnetic precursor length is of $\Delta z$ $\sim$ 0.0005-0.001 pc = 1.5- $3.0\times 10^{15}$ cm.
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In the text

$\begin{figure} \par\includegraphics[angle=270, width=18cm]{8054fig4.eps} \end{figure}$ Figure 4: Evolution of the abundance of elemental silicon ejected from grains by the impact with H₂, He, C, O, Si, Fe, and CO, for initial H₂ densities of 10⁴, 10⁵, and 10⁶ cm^-3 and shock velocities of 20 and 40 km s^-1.
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In the text

$\begin{figure} \par\includegraphics[angle=270, width=18cm]{8054fig5.eps} \end{figure}$ Figure 5: Abundance of elemental silicon ejected from grains by the impact with H₂, He, C, O, Si, Fe, and CO, for shock velocities of 10, 20, 30, and 40 km s^-1 and a H₂ gas density of 10⁵ cm^-3. For each shock velocity, we show the individual production of silicon from the mantles ( upper panels), from the cores ( middle panels), and the total production of silicon from grains ( lower panels).
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In the text

$\begin{figure} \par\includegraphics[angle=0, width=8.5cm]{8054fig6.eps} % \end{figure}$ Figure 6: Predicted SiO abundances within a 30 km s^-1 and a 60 km s^-1 shock as a function of the flow time (see shock parameters in Table 6). Observational SiO abundances derived in the ambient gas (filled square), the precursor component (filled circle), the moderate-velocity gas (filled triangles), and the high-velocity regime (filled stars) found in the L1448-mm outflow (Martín-Pintado et al. 1992; Jiménez-Serra et al. 2005), are also shown. The black arrow indicates an upper limit to the SiO abundance. The observed flow times have been derived from Eq. (2) of Sect. 2 (see text and Appendix A for details).
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In the text

$\begin{figure} \par\includegraphics[angle=0, width=8.7cm]{8054fig7.eps} % \end{figure}$ Figure 7: Upper and middle panels: predictions of the sputtered abundances of CH₃OH and H₂O as a function of the flow time, for a sample of C-shocks with $v_ {\rm s}=10$ , 20, 30, and 40 km s^-1 and n₀=10⁵ cm^-3. Lower panel: SiO, CH₃OH, and H₂O abundances ejected from the grain mantles for the 30 km s^-1-shock of Table 6 as a function of time. We also show the SiO, CH₃OH, and H₂O abundances measured in the ambient gas (square), the precursor component (circles), and the moderate velocity gas (triangles) of the L1448-mm outflow (Benedettini et al. 2002; Jiménez-Serra et al. 2005). Vertical arrows indicate upper limits to the SiO abundance.
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In the text

$\begin{figure} \par\includegraphics[angle=270, width=7.5cm]{8054fig2.eps} % \end{figure}$	Figure 2: Comparison between the profiles of $v_{\rm n}$ , $v_{\rm i}$ and $T_{\rm n}$ derived with our approximation ( lower panel) and the MHD shock structure obtained by Kaufman & Neufeld (1996) for a shock with $v_{\rm s}=35$ km s^-1 and n₀=10⁸ km s^-1 ( upper panel). Parameters are given in Table 3 and velocities are in the shock frame.
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$\begin{figure} \par\includegraphics[angle=0, width=8.5cm]{8054fig3.eps} \end{figure}$	Figure 3: C-shock physical structure obtained with Eqs. (1), (3), and (4) for $v_{\rm s}=40$ km s^-1, n₀= 10⁵ cm^-3, and T₀=10 K. Velocities are in the frame co-moving with the preshock gas. The magnetic precursor length is of $\Delta z$ $\sim$ 0.0005-0.001 pc = 1.5- $3.0\times 10^{15}$ cm.
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$\begin{figure} \par\includegraphics[angle=270, width=18cm]{8054fig4.eps} \end{figure}$	Figure 4: Evolution of the abundance of elemental silicon ejected from grains by the impact with H₂, He, C, O, Si, Fe, and CO, for initial H₂ densities of 10⁴, 10⁵, and 10⁶ cm^-3 and shock velocities of 20 and 40 km s^-1.
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