Parameterization of the ﹩{{\rm{H}}}_{2}\mathrm{CO}﹩ abundance. The gas temperature of the disk (in Kelvin) is shown in black contours, and the gas density (in units of ﹩\,{\mathrm{cm}}^{-3}﹩) is shown in gray contours. The two ﹩{{\rm{H}}}_{2}\mathrm{CO}﹩ components considered in our model are shown in purple shades. The parameters that are kept constant in the model are shown in black, and those that are left free are shown in blue.