Top: altitude A(r) of the molecular layer as a function of radius. The black curve is the HCN(4-3) altitude for comparison. The cyan region indicates the approximate size of the dust disk. The dotted line corresponds to z/r = 0.2. Bottom: deconvolved thickness of the molecular layer. The deconvolution has been done assuming Gaussian shapes using the clean beam minor axis since synthesized beams are elongated almost parallel to the disk plane. The black curve is the HCN(4-3) thickness, for comparison. The cyan bar marks the edge of the dust disk.