Upper panels: radial dependence of the integrated brightness temperature (for lines) and brightness temperature (for continuum emission) in the disk plane. The horizontal sticks indicate the angular resolutions. Lower panels: azimuthal dependence of the same quantities averaged over the ring of 1.2″ < r < 2.0″. Left panels: plot of the emission from the J = 6–5, 3–2 and 2–1 lines of ¹²CO. For a description of the corresponding data, see Tang et al. (2016) for the J = 3–2 line and Dutrey et al. (2014) for the others. Right panels: less abundant CO isotopologs (J = 3–2) emissions. The gray region delineates the dust ring in the upper panels. In the lower panels, black arrows show the location of the limb-brightening peaks and the magenta lines show the hot-spot location.