Results of the model for IRC+10420 (red line) overlaid on the line profiles presented in Fig. 5, as well as recent IRAM 30 m data of the J = 1−0 and J = 2−1 transitions from Quintana-Lacaci et al. (in prep.) and the ¹²CO J = 3−2 and J = 4−3 transitions from the JCMT archive. Note that no data were found for the J = 3−2 and J = 4−3 transitions of ¹³CO. For each line, the model was adjusted by a free corrective factor of at most the absolute-calibration accuracy error, which was applied to the given transition. For the JCMT archive data, this calibration accuracy was unclear to us so we used a conservative upper limit of the 25% error. For the IRAM 30 m data, calibration errors of 20% were assumed at both 3 mm and 1 mm. The correction factor is indicated in the upper right corner of each box.