Top panels: show the thermal dust continuum emission map at frequency 278 GHz predicted by the models of Commerçon et al. (2011), which reproduce the gravitational collapse of a 300 M_⊙ clump in case of strong magnetic support (μ = 2) at time t₂ = 48 500 yr after the birth of the first protostar (see main text for details). In the bottom panels, we show the models after processing in the CASA simulator, adopting the same observational conditions as for the real observations. Units of the colour-scale are Jansky/beam. Contour levels are 0.6, 1, 5, 10, 30, and 50 mJy beam^-1 in all bottom panels.