Synthetic surface brightness profiles obtained, using Thebault (2012)’s numerical model, for 3 different masses of a putative perturbing outer planet: 8   M_Jup, 5   M_Jup and 3   M_Jup. For each case, the planet has a circular orbit and is placed as close as possible to the main ring of large parent bodies in order to truncate it at about 75 AU without destroying it (see text for more details). The observed profile, derived from Schneider et al. (2009), is shown for comparison. For each planet mass, we show the radial cut (i.e., for one position angle along the disk) that provides the best fit to this observed profile. The horizontal line delineates approximately the part (above this line) of the SBD accessible to the observations assuming a dynamical range of 10.