Intensity distribution cuts along the major and minor axes (see Fig. 3) in observations and simulations at 1.3, 2.9, and 8.1 mm. The pixel size at each wavelength is listed in the caption of Fig. 3. The central peak at 8.1 mm was masked for fitting (marked with thick line, see details in Sect. 3.7 and Fig. 3). Lowest panel: 8.1 mm free-free emission is included by assuming a point source with flux ~77 μJy (see Sect. 5.1).