Abstract
dc:description.abstractSubject of this work is the study of applications of the Galactic Microlensing effect, where the light of a distant star (source) is bend according to Einstein's theory of gravity by the gravitational field of intervening compact mass objects (lenses), creating multiple (however not resolvable) images of the source. Relative motion of source, observer and lens leads to a variation of deflection/magnification and thus to a time dependant observable brightness change (lightcurve), a so-called microlensing event, lasting weeks to months. The focus lies on the modeling of binary-lens events, which provide a unique tool to fully characterize the lens-source system and to detect extra-solar planets around the lens star. Making use of the ability of genetic algorithms to efficiently explore large and intricate parameter spaces in the quest for the global best solution, a modeling software (Tango) for binary lenses is developed, presented and applied to data sets from the PLANET microlensing campaign. For the event OGLE-2002-BLG-069 the 2nd ever lens mass measurement has been achieved, leading to a scenario, where a G5III Bulge giant at 9.4 kpc is lensed by an M-dwarf binary with total mass of M=0.51 solar masses at distance 2.9 kpc. Furthermore a method is presented to use the absence of planetary lightcurve signatures to constrain the abundance of extra-solar planets.
Degree
thesis:*- Level thesis:degree_level
- thesis.doctoral
- Grantor dc:publisher
- Universität Potsdam
- Year
- 2005
Author and committee
dc:creator, dc:contributor.*- Author dc:creator
-
- Kubas, Daniel
- Contributors dc:contributor
-
- Wambsganß, Joachim
Subjects
dc:subject × 8Identifiers
dc:identifier.*- Repository record source_url
- https://publishup.uni-potsdam.de/frontdoor/index/index/docId/458
- OAI identifier oai:identifier
- oai:kobv.de-opus4-uni-potsdam:458