Dr. Randall Wayth, CfA

"Dissecting galaxies with strong gravitational lensing"

Abstract: 
Strong gravitational lensing of resolved background sources
can form partial or full Einstein ring images. Such lensing provides a
wealth of information about the mass distribution in the lensing galaxy
in the region of the image, which is typically around the scale length
of the galaxy's light profile. Strong lensing thus allows measurements
of the morphological properties of dark halos at relatively small
galactic radii.
In this talk I will introduce my lensed image analysis software,
Lensview, and show how the visible and dark matter distributions in
lensing galaxies can be separated. I show for some example cases that
the shapes of the lens galaxy dark halos are quite round, more so than
is expected from simulations.