Weighing the giants : methods and measurements of accurate galaxy cluster weak-lensing masses

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Abstract/Contents

Abstract
Clusters of galaxies have become a cornerstone of the experimental evidence supporting the standard Lambda-CDM cosmological model, and will be a mainstay in testing the nature of dark energy with upcoming surveys. To constrain cosmological models, these surveys indirectly measure cluster masses as part of cluster counting experiments, requiring surveys to calibrate their mass proxies. In this thesis, I will present weak-lensing masses for 51 of the most X-ray luminous galaxy clusters known. This cluster sample spans redshifts 0.15 < z < 0.7, and is well suited to calibrate mass proxies for current cluster cosmology experiments. To this end, I will discuss a new weak-lensing method that exploits all information available in the photometric redshift posterior probability distributions of individual galaxies.Using simulations based on the COSMOS-30 catalog, I will demonstrate control of systematic biases in the mean mass of the sample with this method, from photometric redshift biases and associated uncertainties, to better than 3%. The performance of this new photometric redshift-based method allows us to calibrate `color-cut` masses for all 51 clusters in the present sample to a total systematic uncertainty of ~7% on the mean mass, a level sufficient to significantly improve current cosmology constraints from galaxy clusters. Finally, I will discuss how these results bode well for future cosmological studies of clusters.

Description

Type of resource text
Form electronic; electronic resource; remote
Extent 1 online resource.
Publication date 2012
Issuance monographic
Language English

Creators/Contributors

Associated with Applegate, Douglas
Associated with Stanford University, Department of Physics
Primary advisor Allen, Steven W. (Steven Ward)
Thesis advisor Allen, Steven W. (Steven Ward)
Thesis advisor Burchat, P. (Patricia)
Thesis advisor Wechsler, Risa H. (Risa Heyrman)
Advisor Burchat, P. (Patricia)
Advisor Wechsler, Risa H. (Risa Heyrman)

Subjects

Genre Theses

Bibliographic information

Statement of responsibility Douglas Earl Applegate.
Note Submitted to the Department of Physics.
Thesis Thesis (Ph.D.)--Stanford University, 2012.
Location electronic resource

Access conditions

Copyright
© 2012 by Douglas Applegate

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