Surdej, Jean[Université de Liège - ULg > Département d'astrophys., géophysique et océanographie (AGO) > Astroph. extragalactique et observations spatiales (AEOS) >]
proceedings of the 41st ESLAB Symposium "The Impact of HST on European Astronomy" (June 2007)
Astrophysics and Space Science Proceedings series edited by Springer
The 41st ESLAB Symposium "The Impact of HST on European Astronomy" (June 2007)
29 May to 1 June, 2007
[en] Thanks to its sharp view, HST has significantly improved our knowledge of tens of gravitationally lensed quasars in four different respects: (1) confirming their lensed nature; (2) detecting the lensing galaxy responsible for the image splitting; (3) improving the astrometric accuracy on the positions of the unresolved QSO images and of the lens; (4) resolving extended lensed structures from the QSO hosts into faint NIR or optical rings or arcs. These observations have helped to break some degeneracies on the lens potential, to probe the galaxy evolution and to reconstruct the true shape of the QSO host with an increased angular resolution.