Integrated intensity maps (top), integrated 1d-spectral profiles (middle), and axial PV diagrams (bottom) of molecular transitions whose emission is largely restricted to the equatorial waist (Sect. 4.4.1). The integrated intensity maps are superimposed to the 330 GHz-continuum map. The velocity range of the integrated intensity maps of OCS and SO₂ is V_LSR = [18:42] km s⁻¹, and for H₃O⁺ is V_LSR = [14:50] km s⁻¹. Level step in PV diagrams is 3.5 mJy/beam (OCS), 1.5 mJy/beam (H₃O⁺), and 6 mJy/beam (SO₂).