Brightness distributions of HC₃N, SiC₂, C₂H, and HNC, in a3.3 km s⁻¹ wide channel centred on the systemic velocity of IRAS 15194–5115, along a line that intersects the star at PA = 0° (left) and PA = 90° (right). These profiles were extracted from radial cuts using the stacked images shown in Fig. 6. The horizontal shaded region of each profile shows the rms noise of the corresponding emission map.