Image reconstruction for the Einstein cross gravitational lens QSO 2237+0305
Abstract
An image-reconstruction algorithm developed by a group of Belgian scientists based on the regularization method of Tikhonov is studied and applied to images of the gravitational lens QSO 2237+0305 obtained during long-term observations using the 1.5-m telescope at the Ma $$\overset{\lower0.5em\hbox{$\smash{\scriptscriptstyle\smile}$}}{l} $$ danak Observatory. The algorithm separates the observed image into two parts: a (galactic) background plus images of the quasar. The method has enabled appreciable improvement in the accuracy of astrometric and photometric measurements of this gravitational-lens system. The positions of the quasar images are determined with an accuracy of 0″.05, and the brightness of individual components with an accuracy of 0.03m for images with 0″.8.