Title:

Mapping the Dark Matter with COSMOS



Jason Rhodes
Caltech/JPL




Abstract:

Weak gravitational lensing, whereby the images of background
galaxies are slightly distorted by foreground dark matter, has
become the premier tool for examining the dark matter
distribution in the universe. The COSMOS 2 square degree survey
taken with ACS on HST is a superb data set for examining dark
matter via weak lensing due to a unique combination of depth,
resolution, and area.  We present a statistical analysis of the
shear correlation in the COSMOS field and the resulting
constraint on sigma_8.  We also present high resolution maps of
the dark matter distribution in the COSMOS field.  Finally, we
discuss future applications of the COSMOS data set and possible
future space-based weak lensing measurements, which would be
ideal for constraining the properties of dark energy.