Peak intensity contours (red) of the naturally weighted H₂CO2_1,1−2_1,2 emission (θ_FWHM ≈ 1″) from 55 to 62 km s^-1 in the e1/e2 region superposed on the Ku-band continuum image (θ_FWHM ≈ 0.33″). The contours are at 2, 4, 6 mJy/beam. The green circles show the apertures used for the spectra shown in Figs. 16 and 17. The larger apertures around e8mol and e10mol are e8mol_ext and e10mol_ext. The feature denoted “e2-e8 bridge” is a diffuse feature that is seen in the naturally-weighted but not in the robust-weighted images. e2a and e2b in this figure are both associated with the SMA and VLA source e2e (Shi et al. 2010b; Goddi et al. 2016). e2c is associated with the source e2nw.