Minimal lensing solutions in the singular perturbative approach

This paper analyse the properties of minimal solutions for reconstruction lens potential in singular perturbative approach. These corresponds to an expansion with a degree Fourier fields. Using these prevent spurious physically meaningless terms In effect analysis indicates that small change source model will higher order The results are valid not only slightly non-circular sources but also more distorted two. It is thus crucial importance minimize number used modelling lens. Another important asset they offers de-coupling between and help break degeneracy issue. possible drawback under-estimate solution. However this bias has its merit since detection using method ensure real. type be particular interest when considering statistical large lenses, especially light incoming satellite surveys.