Department of Physics & Astronomy

Fall 2008 Colloquia

 

Tesla Jeltema

Tesla Jeltema

Morrison Fellow
University of California Observatories
Can We Constrain Cosmology with Clusters of Galaxies?
December 1, 2008, 4PM, Thornton 411

Large-scale structure has long been known to encode basic information about our universe. One often used cosmological probe are the most massive collapsed objects in the universe, clusters of galaxies, whose formation and evolution depend on the densities of dark matter and dark energy. However, many clusters are not relaxed objects; clusters are built through the accretion of smaller structures and through mergers with neighboring clusters. I will describe efforts to quantify cluster dynamical state through the structure of their X-ray emitting hot gas (i.e. most of the baryons) using both observations and current cosmological simulations. We then investigate the systematic affects of cluster structure on observable cluster properties, which directly affect cosmological constraints through errors on estimates of cluster mass. Finally, I show that we can use observed cluster structure to at least partially correct for these systematic errors.
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