Since 2002 Perimeter Institute has been recording seminars, conference talks, and public outreach events using video cameras installed in our lecture theatres. Perimeter now has 7 formal presentation spaces for its many scientific conferences, seminars, workshops and educational outreach activities, all with advanced audio-visual technical capabilities. Recordings of events in these areas are all available On-Demand from this Video Library and on Perimeter Institute Recorded Seminar Archive (PIRSA). PIRSA is a permanent, free, searchable, and citable archive of recorded seminars from relevant bodies in physics. This resource has been partially modelled after Cornell University's arXiv.org.
Sunyaev-Zel'dovich Effect (SZE) experiments such as the South Pole Telescope (SPT) are currently surveying a large area of sky searching for clusters via their imprint on the CMB. In order to use the resulting cluster catalogues for cosmology, it is necessary to know the mass- and redshift-dependent cluster selection function. I will describe ongoing work to understand and characterize the current SPT cluster yield, using synthetic SZ sky maps constructed from cosmological simulations and noise models calibrated against SPT data.
The APEX Sunyaev Zel'dovich experiment will be described and its performance since first light in 2006 summarized. Recent results will be presented together with plans for future observations/analysis.
An unexpected economic crisis provides an excellent opportunity to better understand the state of Economic theory as a science. While there appears to have been a broad systemic failure within the community of professional economists to predict the current collapse, it must be noted that there have been scattered successes which appear striking and demand our attention.
Extracting compact sources from maps contaminated with noise and unwanted astrophysical signals is a well-studied problem. In anticipation of the now-current generation of large-scale SZ surveys, many authors arrived at the conclusion that a simple multi-scale spatial/spectral filter would be the optimal way to find galaxy clusters in data from these surveys. I will briefly present the basics of the spatial/spectral optimal filter and then show in some detail how this has been implemented in one real-world case, namely in data from the South Pole Telescope (SPT) survey.
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.