A Photometric Survey of Strong Gravitational Lenses

Document Type


Degree Name

Master of Science (MS)


Physics and Astronomy

Date of Award

Summer 2015


Strong gravitational lenses of active galactic nuclei are useful tools for studying many astrophysical issues including the rate of expansion of the universe and the equation of state of dark energy. These issues are highly dependent on the mass distribution near or in the line-of-sight of the lens. Because gravitational lenses often lie in poorly-studied complex environments, models for the mass distribution have been poorly constructed. Over the past decade, our team has been involved in a large study to fully characterize the environments of and line-of-sight structures toward a number of strong gravitational lenses. One vexing problem has been that nearby structures are important contributors to lensing potentials, but our photometry of these is incomplete due to saturation of galaxy cores on the deep images from the project. The purpose of this thesis is to complete a photometric survey of 28 lenses found by CASTLEs that will be combined with a previous study done by Williams et al. (2006). The previous study???s data and my data are combined to form a large catalog of strong gravitational lenses that will be used for further studies.


Kurtis A. Williams

Subject Categories

Physical Sciences and Mathematics | Physics