|Speaker:||Subhabrata Majumdar (Tata Institute, India)|
|Title:||Two Topics in Cluster Cosmology: Studying Dark Energy and Sigma8|
|Date (JST):||Mon, Jun 29, 2009, 13:30 - 14:30|
|Place:||Seminar Room at IPMU Prefab. B|
I will briefly discuss two aspects of cluster cosmology, the first related to probing Dark Energy and the second related to estimating the amplitude of mass fluctuations.
In part one, we look at the prospect of avoiding direct or indirect mass measurements in cluster studies of dark energy, thus bypassing uncertainties due to our incomplete knowledge of mass-observable relations. This will highlight the prospect of using cluster sizes as a cosmological probe from upcoming large yield surveys, both using measurements of SZ and XRay clusters and from using XRay clusters alone.
In part two, we present a new prediction for cluster SZ power spectrum and its implications for the CBI excess. The SZ power spectrum is constructed out of very simple model for cluster structure and evolution which is normalized to XRay observations. Comparison to small scale CMB anisotropies gives an amplitude of mass fluctuations, sigma8, consistent to that obtained from WMAP 5 years data.