for the two-component model are listed in Table \[tab:source\_properties\]. Figure \[fig:aless\_uvplots\] shows the visibility function for the \[\] and 160-$\mu$m continuum, as well as the CO(3–2) observations from @CR18, and the corresponding best-fitting profiles.

In physical units, for the single-Gaussian models, the \[\] and 160-$\mu$m emission are rather compact (0.8–1.4 kpc) in both sources. The \[\] and 160-$\mu$m continuum sizes from the single-Gaussian fitting agree within 1–2$\sigma$ uncertainty. For the two-Gaussian models, the compact and extended \[\] components in ALESS 49.1 have half-light radii of 1.01$\pm$0.12 kpc and 8.7$\pm$1.6 kpc, respectively. The compact and extended 160-$\mu$m components in ALESS 57.1 have half-light radii of 0.86$\pm$0.07 and 5.3$\pm$1 kpc, respectively.

For the two-component \[\] model in ALESS 49.1, the extended \[\] components accounts for up to 80% of the total \[\] luminosity. Note that the systematic uncertainty on this estimate might be significant, as it is unclear how much does the extended component depart from the assumption of a circular Gaussian profile. For the \[\] emission in ALESS 57.1, the single-Gaussian model is preferred. However, if we speculate that ALESS 57.1 has an extended \[\] component with the same size as in ALESS 49.1 ($R_\mathrm{1/2}^\mathrm{ext}=1.01$ arcsec), the 3$\sigma$ upper limit on 