Observed continuum emission at a frequency of 345 GHz, showing the four continuum sources MM1a, MM1b, MM2, and MM3. The beam is shown in the bottom-left corner, and has dimensions 0′′.85 × 0′′.66, with position angle 12.1°. The VLA radio sources VLA1, VLA2, and VLA3 are labelled and marked with black crosses, with the emission peak positions of MM1a and MM1b shown by plus symbols, and the dashed line representing the axis through these positions. Also shown are the large-scale CO emission (red and blue arrows) and the disc-like structure (dotted line) identified by Hutawarakorn et al. (2002).