A combined observational and theoretical study of gravitationally lensed quasars [Elektronische Ressource] / presented by Timo Anguita

A combined observational andtheoretical study of gravitationallylensed quasarsTimo AnguitaAstronomisches Rechen-InstitutZentrum fu¨r Astronomie der Universit¨at HeidelbergHeidelberg 2009Dissertationsubmitted to theCombined Faculties for the Natural Sciences and for Mathematicsof the Ruperto-Carola University of Heidelberg, Germanyfor the degree ofDoctor of Natural Sciencespresented byTimo AnguitaBorn in Santiago, ChilethOral examination: April 15 2009A combined observational and theoretical studyof gravitationally lensed quasarsReferees: Prof. Dr. Joachim WambsganssProf. Dr. Stefan WagnerAbstract.In this thesis we study gravitational lensing of quasars, from strong lensing to microlensing.Weinvestigate onestronglenscandidaterecentlydiscovered intheCOSMOSfield: COSMOS5921+0638. Our analysis of the nature of the lens reveals that the system is composedof an early type foreground galaxy at redshift z =0.551±0.001 lensing a background lowlluminosity AGN and its host galaxy at a candidate redshift of z =3.14±0.05. We show thatsfluxanomalies observed inthelensedimages arelikely duetosubstructureormicrolensingbystars in the lensing galaxy. Extending the analysis of the optical emission of lensed quasars,we have used integral field spectroscopy to study four gravitationally lensed quasar systems:HE 0230-2130, RX J0911+0551, H 1413+117 and B 1359+154, as well as objects in theirline-of-sight.