Black: continuum-subtracted PACS spectrum of R Dor for the blue bands. Red: modelled spectrum. The PACS band is indicated in the upper left corner of each spectrum. The abundance profile used for SiO is characterised by f₀ = 6.0 × 10^-5 relative to H₂ and e-folding radius r_e = 4 × 10¹³ cm with R_decl = 50 R_∗. The abundance profile used for HCN is characterised by f₀ = 5.5 × 10^-7 with respect to H₂ and r_e = 1.5 × 10¹⁵ cm. The modelled transitions are shown by coloured vertical lines: CO in red, SiO in green, and HCN in blue. Dashed lines indicate modelled transitions that were not detected or that contribute to a blended line.