Comparison between alternative models of the HIP 79977 debris disk: “Model 40” with the radius of the planetesimal belt r₀ = 40 AU (left) and “Model 70” with the radius of r₀ = 70 AU (right) and fitting parameters as specified in Table 3. From top to the bottom: a) model of the dust distribution in the disk; b) model of the polarized light; c) model of the polarized light convolved with the instrumental PSF and d) residuals left after subtraction of the PSF-convolved model image from the Q_ϕ image. Color-scales of images a) and b) are given in arbitrary units. Color-bar of images c) and d) shows flux in counts at each pixel of the image.