Millimeter absorption opacity slopes β_mm along the major axis of the disk in the observations and the best-fit model. The slopes β_1.3-2.9mm and β_1.3-8.1mm are derived from spectral indexes α_1.3-2.9mm between 1.3 and 2.9 mm, and α_1.3-8.1mm between 1.3 and 8.1 mm, respectively (see text). All data have been convolved to the angular resolution of the CARMA 2.9 mm map (Table 2). The contribution from free-free emission at 8.1 mm has been removed (see Sect. 3.7 and Fig. 4).