COSMOLOGY WITH OPTICALLY SELECTED GALAXY CLUSTERS: LOOKING FORWARD TO THE DARK ENERGY SURVEY

Galaxy clusters, the largest peaks in the cosmic density field, play an important role in astrophysics and cosmology. By tracing large-scale structure, clusters provide a key opportunity to test our understanding of structure formation, cosmic expansion history, and general relativity. In the next few years, large- scale optical surveys such as the Dark Energy Survey (DES) will detect galaxy clusters to a redshift of ~1 over several thousand square degrees. However, the primary component of galaxy clusters is dark matter, which is not directly observable. I will describe our work to use other observables to estimate cluster mass-galaxy counts, X-ray luminosity, and weak-lensing shear of background galaxies-and how this relates to the opportunities and challenges of using optical clusters to achieve our goals of precision cosmology.

Speaker: Dr. Eli Rykoff, SLAC National Accelerator Laboratory