Total intensity of the ¹²CO and ¹³CO(J = 3 →  2) transitions. The solid black lines are the spectra observed with the APEX telescope in a single pointing towards the star. The solid red line is the emission detected with ALMA in an area equivalent to the APEX beam. The ¹³CO ALMA spectrum has a velocity resolution of 3 km s^-1, the ¹²CO ALMA spectrum has a velocity resolution of 0.5 km s^-1, and the APEX spectra have a velocity resolution of 1.1 km s^-1. The dotted line indicates the ¹³CO model used to fit the ALMA observations (see text) when observed with APEX resolution. The spectra indicate that the ¹²CO and ¹³CO emissions are equally resolved out in the ALMA observations.