The distribution and evolution of cosmic structures, in their dark and baryonic components, remains a source of uncertainty in the current model of the Universe and is an active field of research. To address this subject, we cross-correlate the weak gravitational lensing and thermal Sunyaev-Zel’dovich effects of galaxy clusters as a function of redshift. We use the halo model of large-scale structure to estimate the two-point correlation function between the dark matter density and the gas pressure in halos. After obtaining the three-dimensional power spectrum and projecting it onto the sky by means of Limber’s approximation, we estimate how the cross-correlation between these two types of data builds up as redshift increases. We calculate the covariance matrix for a measured cross-correlation function and evaluate expected error bars for realistic surveys. Further, we examine how the choice of cosmological parameters affects our results and inspect the influence of cluster properties on the cross-correlation signal. We find that, although the cross-correlation signal does not seem to be suitable for constraining cosmological parameters, it is highly sensitive to the intrinsic properties of the clusters and thus provides a way to characterise the evolution of the halo gas component.
|Supervisor:||Bartelmann, Prof. Dr. Matthias|
|Date of thesis defense:||19 December 2012|
|Date Deposited:||16 Jan 2013 08:34|
|Date:||11 January 2013|
|Faculties / Institutes:||The Faculty of Physics and Astronomy > Dekanat der Fakultät für Physik und Astronomie|