Weak gravitational lensing in the red-sequence cluster survey 2

Uitert, E. van (2012)

Doctoral Thesis

In my thesis I study the projected density distribution of all (dark+baryonic) matter around various selections of galaxies and galaxy clusters in the Red-sequence Cluster Survey 2 (RCS2), one of the largest optical imaging surveys to date. This is done by measuring the tiny distortions in the images of background galaxies induced by the gravitational potential of the foreground objects, which are called the lenses. Comparing this so-called weak gravitational lensing signal to model predictions enables us to determine the total mass of the lenses. We study how the total mass relates to, amongst others, the luminosity of the lenses, and to the total mass in stars, which leads to valuable insight into galaxy formation processes. We also study the anisotropy of the weak lensing signal around galaxies, to constrain the average ellipticity of the dark matter haloes in which these galaxies are embedded. Finally, we measure the relation between the total mass of galaxy clusters and the number of cluster members, and how this relation changes with redshift. This is essential for using cluster counts to constrain cosmological parameters, but also contains information of how clusters form.

• Dark matter
• Weak gravitational lensing
• Halo ellipticity
• galaxy formation clusters

• All authors: Uitert, E. van
• Supervisor: Kuijken, K.H.
• Qualification: Doctor (dr.)
• Awarding Institution: Faculty of Science, Leiden University
• Date: 2012-05-29