Placement of the 25 PACS spaxels relative to Fomalhaut (marked by the white star) in the case of the C ii observations. The grey scale indicates the integrated C ii emission for each spaxel within a window of width equal to 2.5*FWHM of the line. The ellipse shows the location of the peak density of mm grains according to the best-fit model by B12. The corresponding figure for the O i data looks very similar. The 15 spaxels with a yellow bold edge were summed to produce Fig. 2.