A general method to reconstruct strong gravitational lenses based on the singular perturbative approach

TL;DR

This paper introduces an automated, general method for reconstructing gravitational lenses and sources from arc images using a singular perturbative approach, enabling statistical analysis of large lens datasets.

Contribution

It presents a novel, fully automated reconstruction method based on singular perturbation that refines solutions step-by-step to handle degeneracies and allows statistical analysis.

Findings

Method successfully reconstructs lens and source from arc images.

Automated approach reduces manual intervention and bias.

Enables statistical analysis of large gravitational lens datasets.

Abstract

The number of gravitational arcs systems detected is increasing quickly and should even increase at a faster rate in the near future. This wealth of new gravitational arcs requires the development of a purely automated method to reconstruct the lens and source. A general reconstruction method based on the singular perturbative approach is proposed in this paper. This method generates a lens and source reconstruction directly from the gravitational arc image. The method is fully automated and works in two steps. The first step is to generate a guess solution based on the circular solution in the singular perturbative approach. The second step is to break the sign degeneracy and to refine the solution by using a general source model. The refinement of the solution is conducted step by step to avoid the source-lens degeneracy issue. One important asset of this automated method is that the lens solution is written in universal terms which allows the computation of statistics. Considering the large number of lenses which should be available in the near future this ability to compute un-biased statistics is an important asset.