Conference

New high-resolution, cosmological-scale simulations of the microwave sky have been created based on the most recent observational data. Currently these imulations are in use by the ACT team to test their data analysis pipeline. These simulations are also flexible enough to be of use to SPT and Planck. We discuss the various components of the simulations, their construction, and comparison to observational data.

A detailed understanding of galaxy clusters is essential in limiting the potential for systematic effects in the use of galaxy clusters for cosmological measurements. I will synthesize our current work on understanding the stellar components of galaxy clusters, including the intergalactic stellar populations and the structural relationship between stellar populations in galaxies and clusters. Ultimately, the characterization of the relationship between dark matter halos and the stellar populations within them will play a key role in unraveling what clusters tell us about the Universe.

The Red-Sequence Cluster Survey (RCS2) is a 1000-square-degree, multi-color imaging survey carried out using MegaCam on the 3.6m CFHT which is optimized for the search of galaxy clusters with 0.15

The largest structures in the Universe -- Superclusters of Galaxies -- range in size from a few Mpc to the 'Great Walls' scale of hundreds of Mpc. What is the shape of these large structures -- are they filamentary in nature or are they flattened two-dimensional 'pancakes'? How do they form and evolve? Superclusters are typically dominated by clusters of galaxies, systems that serve as one of the most powerful tools in cosmology. What is the shape of clusters -- are they spherically symmetric or are they elongated? Are they aligned with each other on large scales? I present results that answer these fundamental questions, revealing the predicted shape and evolution of the large-scale structure in the Universe in the current popular cosmology. We show that the shape of clusters provides an interesting new tool in constraining cosmology, as well as provides clues to the formation and evolution of large-scale structure.

In 2001 we made an unexpected discovery of a very bright SZ spot toward the X-ray luminous cluster RXJ1347-1145, which was significantly displaced from the center of the cluster's gravitational potential. One of the possible interpretations is that this spot is a signature of a violent merger in this cluster. This sypothesis has been confirmed by the subsequent Chandra X-ray observations. In this talk I will report on recent results from our follow-up observation of XJ1347-1145 with Suzaku X-ray telescope. Our studies show that the SZ effect, when it is mapped with a fine angular resolution of order 10 arc-seconds, provides a powerful probe of violent cluster mergers.

The coming era of large, multi-wavelength surveys motivates and, ultimately, will inform a multivariate statistical framework describing cluster properties in relation to underlying halo mass and redshift. In this talk, I will present work at Michigan that focuses on a multivariate Gaussian likelihood approach to this problem, and includes empirical studies using optical and X-ray observations of the SDSS maxbcg sample as well as a computational program using Gadget resimulations of the Millennium Simulation with preheated gas dynamics. I will show evidence from the models that a combination of fgas measurements from X-rays along with Ytot from thermal SZ can constrain mass at the rms level of 4%.