Fiducial model: (top left) surface density profile; (top middle) gas density structure: the τ = 1 layer of the J = 2−1 transition is overlaid as the dashed (¹²CO), dot-dashed (¹³CO), and solid (C¹⁸O) curve; (top right) dust density structure; (bottom left) spectral energy distribution with fiducial model (black solid curve): data (red dots) are from IRAS, Herschel (Pascual et al. 2016), SCUBA (Sandell et al. 2011), and ALMA (this work); (bottom middle) gas temperature structure; (bottom right) dust temperature structure.