All Figures

$\begin{figure} {\includegraphics[width=7.3cm,clip]{0546fig58.ps} }\end{figure}$ Figure 1: L-packet injection into the core: the packet is injected from a random point ( $\theta$ , $\phi$ ) on the surface of the sphere at such an angle ( $\theta _{\rm in}$ , $\phi _{\rm in}$ ) as to imitate an isotropic radiation field. The frequency of the injected packet is chosen from the Black (1994) radiation field.
Open with DEXTER

In the text

$\begin{figure} \par { \includegraphics[angle=-90,width=5.75cm,clip]{0546fig1.ps}... ...,clip]{0546fig4.ps} } \vspace{-3cm}\hspace{1cm}{d}\vspace{+3cm} \par\end{figure}$ Figure 2: Density distribution on the x=0 plane a) for a flattened asymmetric core with equatorial-to-polar optical depth ratio e=1.5 and p=4 (model 1.1), b) for a more flattened asymmetric core, with e=2.5 and p=4 (model 1.2), c) for a core with e=1.5 and p=1 (model 1.3), and d) for a more flattened core, with e=2.5 and p=1 (model 1.4). We plot iso-density contours every $10^{0.5}~{\rm cm^{-3}}$ . The central contour corresponds to $n=10^{5.5}~{\rm cm^{-3}}$ .
Open with DEXTER

In the text

$\begin{figure} { \includegraphics[angle=-90,width=5.7cm]{0546fig5.ps} } \vspace{... ....7cm,clip]{0546fig8.ps} } \vspace{-3cm}\hspace{1cm}{d}\vspace{+3cm} \end{figure}$ Figure 3: Temperature distribution on the x=0 plane, for the models presented in Fig. 2. We plot iso-temperature contours from 8 to 18 K, every 2 K.
Open with DEXTER

In the text

$\begin{figure} \par {\includegraphics[width=6.5cm,clip]{0546fig9.ps} }\end{figure}$ Figure 4: SED for the core models in Figs. 2 and 3; model 1.1 (e=1.5, p=4; short-dashed line), model 1.2 (e=2.5, p=4; solid line), model 1.3 (e=1.5, p=1; dash-dot line) and model 1.4 (e=2.5, p=1; long-dashed line). The SED of each core is independent of the observer's viewing angle. The dotted line on the graph corresponds to the incident/background SED.
Open with DEXTER

In the text

$\begin{figure} \par {\includegraphics[width=6.5cm,clip]{0546fig10.ps} } \end{figure}$ Figure 5: A perpendicular cut through the centre of the core images presented in Fig. 7 for model 1.2 at 200 $\mu {\rm m}$ (but also including the background radiation field). In addition we plot the beam size of ISO/ISOPHOT ( $90\hbox {$^{\prime \prime }$ }\equiv 9000$ AU for a core at 100 pc) and the beam size of the upcoming (2007) Herschel ( $13\hbox {$^{\prime \prime }$ }\equiv 1300$ AU for the $170~\mu {\rm m}$ band of PACS and $17\hbox {$^{\prime \prime }$ }\equiv 1700$ AU for the $250~\mu {\rm m}$ band of SPIRE). ISO's resolution may not be good enough to detect any of the features on the graph, but Herschel will have a much better resolution and should be able to detect such features in the future.
Open with DEXTER

In the text

$\begin{figure} \par {\includegraphics[angle=-90,width=5.8cm,clip]{0546fig11.ps} ... ...mm} {\includegraphics[angle=-90,width=5.8cm,clip]{0546fig14.ps} } \end{figure}$ Figure 6: Isophotal maps at 200 $\mu {\rm m}$ at viewing angles $0\hbox {$^\circ $ }$ , $30\hbox {$^\circ $ }$ , $60\hbox {$^\circ $ }$ and $90\hbox {$^\circ $ }$ , for a flattened core with equatorial-to-polar optical depth ratio e=1.5 and p=4 (model 1.1). We plot an isophotal contour at 5 MJy sr^-1 and then from 60 to 110 MJy sr^-1, every 5 MJy sr^-1. There are characteristic symmetric features due to core temperature and orientation with respect to the observer. We note that in these isophotal maps, and in all subsequent isophotal maps, the axes (x,y) refer to the plane of sky as seen by the observer.
Open with DEXTER

In the text

$\begin{figure} \par {\includegraphics[angle=-90,width=5.8cm,clip]{0546fig15.ps} ... ...\par {\includegraphics[angle=-90,width=5.8cm,clip]{0546fig18.ps} }\end{figure}$ Figure 7: Same as Fig. 6, but for a more flattened core, with equatorial-to-polar optical depth ratio e=2.5 and p=4 (model 1.2).
Open with DEXTER

In the text

$\begin{figure} \par {\includegraphics[angle=-90,width=5.9cm,clip]{0546fig19.ps} ... ...par {\includegraphics[angle=-90,width=5.9cm,clip]{0546fig22.ps} } \end{figure}$ Figure 8: Same as Fig. 6, but for a core with equatorial-to-polar optical depth ratio e=1.5 and p=1 (model 1.3).
Open with DEXTER

In the text

$\begin{figure} \par {\includegraphics[angle=-90,width=6.cm,clip]{0546fig23.ps} }... ...{2mm} {\includegraphics[angle=-90,width=6.cm,clip]{0546fig26.ps} }\end{figure}$ Figure 9: Same as Fig. 6, but for a core with equatorial-to-polar optical depth ratio e=2.5 and p=1 (model 1.4).
Open with DEXTER

In the text

$\begin{figure} \par {\includegraphics[angle=-90,width=6.1cm,clip]{0546fig27.ps} ... ...3mm} {\includegraphics[angle=-90,width=6.1cm,clip]{0546fig30.ps} }\end{figure}$ Figure 10: Isophotal maps at 850 $\mu {\rm m}$ at viewing angles $0\hbox {$^\circ $ }$ , $30\hbox {$^\circ $ }$ , $60\hbox {$^\circ $ }$ and $90\hbox {$^\circ $ }$ , for a flattened core with equatorial-to-polar optical depth ratio e=1.5 and p=4 (model 1.1). We plot an isophotal contour at 1 MJy sr^-1 and then from 5 to 50 MJy sr^-1, every 5 MJy sr^-1. The core appears elongated when viewed at an angle other than $\theta =0\hbox {$^\circ $ }$ .
Open with DEXTER

In the text

$\begin{figure} \par {\includegraphics[angle=-90,width=6.1cm,clip]{0546fig31.ps} ... ...\par {\includegraphics[angle=-90,width=6.1cm,clip]{0546fig34.ps} }\end{figure}$ Figure 11: Same as Fig. 10, but for a more flattened core, with equatorial-to-polar optical depth ratio e=2.5 and p=4 (model 1.2).
Open with DEXTER

In the text

$\begin{figure} \par {\includegraphics[angle=-90,width=6.1cm,clip]{0546fig35.ps} ... ...2mm} {\includegraphics[angle=-90,width=6.1cm,clip]{0546fig38.ps} }\end{figure}$ Figure 12: Same as Fig. 10, but for a core with equatorial-to-polar optical depth ratio e=1.5 and p=1 (model 1.3).
Open with DEXTER

In the text

$\begin{figure} \par {\includegraphics[angle=-90,width=6.1cm,clip]{0546fig39.ps} ... ...2mm} {\includegraphics[angle=-90,width=6.1cm,clip]{0546fig42.ps} }\end{figure}$ Figure 13: Same as Fig. 10, but for a core with equatorial-to-polar optical depth ratio e=2.5 and p=1 (model 1.4).
Open with DEXTER

In the text

$\begin{figure} \par { \includegraphics[width=6.3cm,clip]{0546fig43.ps} }\end{figure}$ Figure 14: The effect of the parent cloud on cores. Temperature profiles of a non-embedded core (model 1.2; dashed lines), and of a core at the centre of an ambient cloud with visual extinction $A_{\rm V}=4$ (dotted lines), and $A_{\rm V}=13$ (solid lines). The upper curve of each set of lines corresponds to the direction towards the pole of the core ( $\theta =0\hbox {$^\circ $ }$ ), and the bottom curve to the direction towards the core equator ( $\theta =90\hbox {$^\circ $ }$ ). The core is colder when it resides inside a thicker parent cloud (i.e. when it is illuminated by a radiation field that is weakened at short (< $10~\mu {\rm m}$ ) wavelengths), and the temperature differences between different parts of the core are smaller. Thus, the characteristic features on the isophotal maps at wavelengths near the peak of the core SED are weakened.
Open with DEXTER

In the text

$\begin{figure} \par {\includegraphics[width=6cm,angle=-90]{0546fig44.ps} }\end{figure}$ Figure 15: Temperature distribution on the x=0 plane, for the same model presented in Figs. 2b and 3b (e=2.5, p=4, model 1.2), but embedded in the centre of an ambient molecular cloud with visual extinction $A_{\rm V}=4$ . We plot iso-temperature contours from 8 to 13 K, every 1 K. The embedded core is colder than the non-embedded core (Fig. 3b) and the temperature gradient inside the core is smaller.
Open with DEXTER

In the text

$\begin{figure} \par { \includegraphics[width=6.5cm,clip]{0546fig45.ps} }\end{figure}$ Figure 16: Same as Fig. 5, i.e. model 1.2, but for a core embedded in a uniform molecular ambient cloud with visual extinction $A_{\rm V}=4$ . The characteristic features visible at different viewing angles are weaker than in the case of a non-embedded core.
Open with DEXTER

In the text

$\begin{figure} \par {\includegraphics[width=6.5cm,clip]{0546fig46.ps} }\end{figure}$ Figure 17: Same as Fig. 5, i.e. model 1.2, but for a core embedded in a uniform molecular ambient cloud with visual extinction $A_{\rm V}=13$ . There are two characteristic intensity minima visible at viewing angles 60 $^{\rm o}$ and 90 $^{\rm o}$ , but at viewing angles 0 $^{\rm o}$ and 30 $^{\rm o}$ these features are essentially invisible.
Open with DEXTER

In the text

$\begin{figure} \par { \includegraphics[width=6.3cm,clip]{0546fig47.ps} }\end{figure}$ Figure 18: The effect of an UV-enhanced ISRF on embedded cores. Temperature profiles of a core with the same set of parameters as model 1.2 (p=4, e=2.5), embedded in a uniform density ambient cloud with visual extinction $A_{\rm V}=13$ , that is illuminated by the BISRF (solid lines), by the BISRF plus a diluted blackbody of $T_\star =6000$ K (dotted lines) and by the BISRF plus a diluted blackbody of $T_\star=10~000$ K (dashed lines). The upper curve of each set of lines corresponds to the direction towards the pole of the core ( $\theta =0\hbox {$^\circ $ }$ ), and the bottom curve to the direction towards the core equator ( $\theta =90\hbox {$^\circ $ }$ ). The core is hotter when the illuminating radiation field is enhanced at UV wavelengths, but the temperature differences between different parts of the core are not significantly increased.
Open with DEXTER

In the text

$\begin{figure} \par { \includegraphics[angle=-90,width=7cm,clip]{0546fig48.ps} } \end{figure}$ Figure 19: Density distribution on the x=0 plane for a core with axial asymmetry, south-to-north pole optical depth ratio e=2.5 and p=4 (model 2.2). We plot iso-density contours every $10^{0.5}~{\rm cm^{-3}}$ . The central contour corresponds to $n=10^{5.5}~{\rm cm^{-3}}$ .
Open with DEXTER

In the text

$\begin{figure} \par { \includegraphics[angle=-90,width=7cm,clip]{0546fig49.ps} } \end{figure}$ Figure 20: Temperature distribution on the x=0 plane, for the model presented in Fig. 19 (e=2.5, p=4, model 2.2). We plot iso-temperature contours from 8 to 18 K, every 2 K. The denser, southern parts of the core are colder.
Open with DEXTER

In the text

$\begin{figure} \par {\includegraphics[angle=-90,width=6.1cm,clip]{0546fig50.ps} ... ...4mm} {\includegraphics[angle=-90,width=6.1cm,clip]{0546fig53.ps} }\end{figure}$ Figure 21: Isophotal maps at 200 $\mu {\rm m}$ at viewing angles $0\hbox {$^\circ $ }$ , $30\hbox {$^\circ $ }$ , $60\hbox {$^\circ $ }$ and $90\hbox {$^\circ $ }$ , for a flattened core with south-to-north pole optical depth ratio e=2.5 and p=4 (model 2.2). We plot an isophotal contour at 5 MJy sr^-1 and then from 60 to 110 MJy sr^-1, every 5 MJy sr^-1.
Open with DEXTER

In the text

$\begin{figure} {\includegraphics[angle=-90,width=6.1cm,clip]{0546fig54.ps} }\vsp... ...{3mm} {\includegraphics[angle=-90,width=6.1cm,clip]{0546fig57.ps} } \end{figure}$ Figure 22: Isophotal maps at 850 $\mu {\rm m}$ at viewing angles $0\hbox {$^\circ $ }$ , $30\hbox {$^\circ $ }$ , $60\hbox {$^\circ $ }$ and $90\hbox {$^\circ $ }$ , for a flattened core with south-to-north pole optical depth ratio e=2.5 and p=4 (model 2.2). We plot an isophotal contour at 1 MJy sr^-1 and then from 5 to 50 MJy sr^-1, every 5 MJy sr^-1. The core appears elongated when viewed at an angle other than $\theta =0\hbox {$^\circ $ }$ .
Open with DEXTER

In the text

$\begin{figure} {\includegraphics[width=7.3cm,clip]{0546fig58.ps} }\end{figure}$	Figure 1: L-packet injection into the core: the packet is injected from a random point ( $\theta$ , $\phi$ ) on the surface of the sphere at such an angle ( $\theta _{\rm in}$ , $\phi _{\rm in}$ ) as to imitate an isotropic radiation field. The frequency of the injected packet is chosen from the Black (1994) radiation field.
Open with DEXTER

$\begin{figure} { \includegraphics[angle=-90,width=5.7cm]{0546fig5.ps} } \vspace{... ....7cm,clip]{0546fig8.ps} } \vspace{-3cm}\hspace{1cm}{d}\vspace{+3cm} \end{figure}$	Figure 3: Temperature distribution on the x=0 plane, for the models presented in Fig. 2. We plot iso-temperature contours from 8 to 18 K, every 2 K.
Open with DEXTER

$\begin{figure} \par {\includegraphics[width=6.5cm,clip]{0546fig9.ps} }\end{figure}$	Figure 4: SED for the core models in Figs. 2 and 3; model 1.1 (e=1.5, p=4; short-dashed line), model 1.2 (e=2.5, p=4; solid line), model 1.3 (e=1.5, p=1; dash-dot line) and model 1.4 (e=2.5, p=1; long-dashed line). The SED of each core is independent of the observer's viewing angle. The dotted line on the graph corresponds to the incident/background SED.
Open with DEXTER

$\begin{figure} \par {\includegraphics[angle=-90,width=5.8cm,clip]{0546fig15.ps} ... ...\par {\includegraphics[angle=-90,width=5.8cm,clip]{0546fig18.ps} }\end{figure}$	Figure 7: Same as Fig. 6, but for a more flattened core, with equatorial-to-polar optical depth ratio e=2.5 and p=4 (model 1.2).
Open with DEXTER

$\begin{figure} \par {\includegraphics[angle=-90,width=5.9cm,clip]{0546fig19.ps} ... ...par {\includegraphics[angle=-90,width=5.9cm,clip]{0546fig22.ps} } \end{figure}$	Figure 8: Same as Fig. 6, but for a core with equatorial-to-polar optical depth ratio e=1.5 and p=1 (model 1.3).
Open with DEXTER

$\begin{figure} \par {\includegraphics[angle=-90,width=6.cm,clip]{0546fig23.ps} }... ...{2mm} {\includegraphics[angle=-90,width=6.cm,clip]{0546fig26.ps} }\end{figure}$	Figure 9: Same as Fig. 6, but for a core with equatorial-to-polar optical depth ratio e=2.5 and p=1 (model 1.4).
Open with DEXTER

$\begin{figure} \par {\includegraphics[angle=-90,width=6.1cm,clip]{0546fig31.ps} ... ...\par {\includegraphics[angle=-90,width=6.1cm,clip]{0546fig34.ps} }\end{figure}$	Figure 11: Same as Fig. 10, but for a more flattened core, with equatorial-to-polar optical depth ratio e=2.5 and p=4 (model 1.2).
Open with DEXTER

$\begin{figure} \par {\includegraphics[angle=-90,width=6.1cm,clip]{0546fig35.ps} ... ...2mm} {\includegraphics[angle=-90,width=6.1cm,clip]{0546fig38.ps} }\end{figure}$	Figure 12: Same as Fig. 10, but for a core with equatorial-to-polar optical depth ratio e=1.5 and p=1 (model 1.3).
Open with DEXTER

$\begin{figure} \par {\includegraphics[angle=-90,width=6.1cm,clip]{0546fig39.ps} ... ...2mm} {\includegraphics[angle=-90,width=6.1cm,clip]{0546fig42.ps} }\end{figure}$	Figure 13: Same as Fig. 10, but for a core with equatorial-to-polar optical depth ratio e=2.5 and p=1 (model 1.4).
Open with DEXTER

$\begin{figure} \par { \includegraphics[width=6.5cm,clip]{0546fig45.ps} }\end{figure}$	Figure 16: Same as Fig. 5, i.e. model 1.2, but for a core embedded in a uniform molecular ambient cloud with visual extinction $A_{\rm V}=4$ . The characteristic features visible at different viewing angles are weaker than in the case of a non-embedded core.
Open with DEXTER

$\begin{figure} \par {\includegraphics[width=6.5cm,clip]{0546fig46.ps} }\end{figure}$	Figure 17: Same as Fig. 5, i.e. model 1.2, but for a core embedded in a uniform molecular ambient cloud with visual extinction $A_{\rm V}=13$ . There are two characteristic intensity minima visible at viewing angles 60 $^{\rm o}$ and 90 $^{\rm o}$ , but at viewing angles 0 $^{\rm o}$ and 30 $^{\rm o}$ these features are essentially invisible.
Open with DEXTER

$\begin{figure} \par { \includegraphics[angle=-90,width=7cm,clip]{0546fig48.ps} } \end{figure}$	Figure 19: Density distribution on the x=0 plane for a core with axial asymmetry, south-to-north pole optical depth ratio e=2.5 and p=4 (model 2.2). We plot iso-density contours every $10^{0.5}~{\rm cm^{-3}}$ . The central contour corresponds to $n=10^{5.5}~{\rm cm^{-3}}$ .
Open with DEXTER

$\begin{figure} \par { \includegraphics[angle=-90,width=7cm,clip]{0546fig49.ps} } \end{figure}$	Figure 20: Temperature distribution on the x=0 plane, for the model presented in Fig. 19 (e=2.5, p=4, model 2.2). We plot iso-temperature contours from 8 to 18 K, every 2 K. The denser, southern parts of the core are colder.
Open with DEXTER

$\begin{figure} \par {\includegraphics[angle=-90,width=6.1cm,clip]{0546fig50.ps} ... ...4mm} {\includegraphics[angle=-90,width=6.1cm,clip]{0546fig53.ps} }\end{figure}$	Figure 21: Isophotal maps at 200 $\mu {\rm m}$ at viewing angles $0\hbox {$^\circ $ }$ , $30\hbox {$^\circ $ }$ , $60\hbox {$^\circ $ }$ and $90\hbox {$^\circ $ }$ , for a flattened core with south-to-north pole optical depth ratio e=2.5 and p=4 (model 2.2). We plot an isophotal contour at 5 MJy sr^-1 and then from 60 to 110 MJy sr^-1, every 5 MJy sr^-1.
Open with DEXTER