Notes. The data for the ¹²CO(3 − 2) and ¹²CO(5 − 4) emission lines are from Neri et al. (2020). The fitting of each line is shown in Fig. 5. When one parameter is quoted without uncertainty, its value was fixed during the fitting procedure. The observed line luminosities have been derived using the standard relation given by Solomon & Vanden Bout (2005) – see Sect. 6.2 and Eq. (6). ^( * )Combination of the two Gaussian components. ^( * *)Only the visible red component. ^{( * * * )}Net absorption only. ^( † )The two NH₂ transitions are (2₀₂ − 1₁₁) (5/2 − 3/2) and (2₂₀ − 2₁₁) (5/2 − 3/2), respectively. In the case of the latter transition, we provide a 3σ upper limit. ^( ‡ )In the case of the absorption line observed at 246.72 GHz, we here provide the derived properties for HCN and NH separately, noting that both molecules likely do contribute to the observed absorption (see Sect. 8.1).