Intensity maps of PN and SiO integrated in velocity. (a) PN J = 2−1 integrated in the range 85.7–105.8 km s⁻¹. The white contour is the 3σ rms level of the integrated map (σ = 1.14 × 10⁻² Jy km s⁻¹ ), while the black contours are in steps of 1σ rms. The numbered regions 1 and 2 are those used to extract the spectra of all species analysed. The synthesised beam is in the bottom-left corner. The yellow contour is the 3 mm continuum emission at 16 mJy beam⁻¹, corresponding to 20σ rms. The yellow stars indicate the continuum sources identified by Beltrán et al. (2021). (b) Map of the intensity of SiO J = 2 − 1 integrated in the same velocity range as PN (colour scale). The PN emission regions identified in panel a are highlighted in white. Contours start at the 3σ rms level of the integrated emission (3 × 10⁻² Jy kms⁻¹ ), and correspond to 3, 15, 30, 50, 80, and 120σ. (c) Spectra of PN J = 2 − 1 extracted from the emission peak in regions 1 (upper panel) and 2 (lower panel). The red dashed horizontal line indicates the 3σ rms level, and the vertical lines show the position in velocity of the line hyperfine components. (d) SiO J = 2 − 1 emission integrated in the velocity ranges 63.5–85.7 km s⁻¹ (blue contours) and 105.8–130.0 km s⁻¹ (red contours). In both cases, the starting contour is the 3σ rms level of the integrated map (1.95 × 10⁻² Jy km s⁻¹ for the red contours, 1.62 × 10⁻² Jy km s⁻¹ for the blue contours), and the step is 25σ. The dashed lines correspond to the six outflows identified by Beltrán et al. (2022) from SiO J = 5 − 4. The grey filled areas correspond to the PN emission regions 1 and 2 identified in panel a. (e) Same as panel d but for SiO J = 5 − 4, obtained at an angular resolution of ~0.22″ with ALMA, and already published in Beltrán et al. (2018). The integration velocity intervals are the same as in panel d.