Three panels showing a zoom-in of the 21–22 µm region, the 23–24 µm region, and the 23.75–24 µm region, respectively, of the CX Tau spectrum (black). The left and middle panels show a warm H₂O slab model in light pink (the best-fit model to the 13.5–17.5 µm region), a colder (175 K) slab model in light blue and an OH slab model in magenta. Blue and red triangles denote H₂O lines that demonstrate the presence of a cold H₂O component in CX Tau (see text). The right panel shows the spectrum of CX Tau in black and the spectrum of DR Tau (Temmink et al. 2024a,b) in dark blue. The spectrum of DR Tau has been scaled to match the flux of the 23.87 µm line.