Fig. 5.

Line integrated intensity ratios. The color maps correspond to I(SO J=5₆→4₅)/I(C¹⁸ O J=2→1), I(SO J=5₆→4₅)/I(H₂CO J=3_0,3→2_0,2), and I(H₂CO J=3₀₃ →2₀₂)/I(C¹⁸O J=2→1) in temperature units. While the I(H₂CO)/I(C¹⁸O) ratio is fairly constant in the disk, the I(SO)/I(C¹⁸O) and I(SO)/I(H₂CO) present a clear NE-SW gradient with its minimum value toward the dust trap. Although there is a large dispersion, there appears to be an anticorrelation with C¹⁸O intensity, which is a measure of column density, which in turn is thought to correlate (assuming a disk-like or ring morphology) with the local density.