JCMT data. Comparison of J = 3–2 (left) and J = 2–1 (right) spectra at four positions of ¹²CO (black), ¹³CO (blue), and C¹⁸O (red). The widest and most intense emission is that of ¹²CO, the narrowest and weakest emission profile is that of C¹⁸O. The dashed line indicates the velocity (2.75 km s⁻¹) of the quiescent gas (see Fig 19). The offsets relative to the 2MASS YSO position are indicated in the left-hand panels (see also Fig. 17).