Model of the small debris disk that could be hidden behind the coronagraphic mask. The model parameterscorrespond to those of the mean model (Table 2) except the radius of the belt and scale height of the dust vertical distribution, which are reduced by a factor of 5. Panel a: Q_φ image of the debris disk model showing the polarized intensity before being convolved with the instrumental PSF. Panel b: Q_φ image of the debris disk model showing the polarized intensity after convolution with the instrumental PSF. The black circle denotes the edge of the coronagraphic mask. Panel c: U_φ image of the model demonstrating nonzero U_φ signal appearing after convolution of the Stokes Q and U parameters with the instrumental PSF. The color bars show counts per pixel.