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	Figure 1: We use an oblate spheroidal sink particle, called a smartie, which contains a central star and a disc, and launches a bipolar outflow.
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In the text

	Figure 2: The star grid consists of concentric spherical surfaces centred on the star, with equal spacing in , and conical surfaces symmetric about the angular momentum of the smartie, with equally spaced opening angle . This grid takes account of the dust-free cavity in the immediate vicinity of the star, and resolves the disc inside the smartie.
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In the text

	Figure 3: Dotted line: the external illumination field (BISRF + emission from PAHs). Solid line: the radiation scattered by the molecular cloud. This is similar for all the time-frames and viewing angles, for the models we examine here.
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In the text

	Figure 4: Cross sections of density and dust temperature on a plane parallel to the x=0 plane ( left two columns) and parallel to the z=0 plane ( right two columns). Each row corresponds to a different time frame from Table 1, top to bottom t0 to t5. The planes are chosen so as to include the maximum density region (t0 and t1) or the protostar (t2 to t5).
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In the text

	Figure 5: Log-log plot of density ( left column) and dust temperature ( right column) versus distance from the centre of coordinates, in a collapsing core which forms a protostar; from top to bottom, time-frames t0 to t5 (see Table 1).
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In the text

Figure 6: SEDs of the 6 time-frames in Table 1, from 3 polar angles ( , , ) and 2 azimuthal angles ( , ); in several cases the SEDs from different viewing angles overlap. a) t0 - precollapse prestellar core. The SED peaks at  , which implies an effective temperature . b) t1 - collapsing prestellar core. The SED appears the same as in (a) although the collapse has started and the cloud is denser and colder at its centre. c) t2 - Class 0 object. The emission of the system peaks at  (depending on the observer's viewing angle), which implies . The total luminosity of the system is higher than in  b). d) t3 - Class 0 object. Similar to (c), but the luminosity is even higher, and the SED peaks at , implying . e) t4 - Class 0 object. Similar to (d), but the luminosity has started to decrease due to the falling accretion rate, and the SED peaks at , implying . f) t5 - Class 0 object. The protostar has moved out of the central region by  , and the attenuated stellar emission can be seen at short wavelengths ( ). The peak of the cloud emission is at , implying .

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In the text

Figure 7: 850 isophotal maps of 3 different time-frames ( first column: t1 - collapsing prestellar core; second column: t3 - Class 0 object; third column: t5 - Class 0 object), and from three different viewing angles (first row: ; second row: ; third row: ). Cores with protostars ( second and third columns) are more centrally condensed than prestellar cores ( first column). We note that the axes (x,y) refer to the plane of sky as seen by the observer.

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In the text

	Figure 8: As Fig. 7, but after convolving with a Gaussian beam having , (or equivalently for a core at ). Cores with protostars ( middle frame, t3; right-hand frame, t5) appear more circular, but otherwise similar to the prestellar core ( left-hand frame, t1).
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In the text