Surface density profiles obtained from fitting the brightness distributions along the disk major axis at each wavelength (see Sect. 3). The dashed line represents a tapered-edge model: Σ(R) ∝ (R/R_C)^{− γ} exp [−(R/R_C)^2−γ] with R_C = 78.9 AU and γ = −0.22 from Kwon et al. (2011). Selected gaps and rings identified by ALMA Partnership et al. (2015) are indicated. Σ_VLA (7 mm) is shown as black, Σ_B3 (2.9 mm) as red, Σ_B6 (1.3 mm) as green, and Σ_B7 (0.87 mm) as blue lines.