Cosmology with the shear-peak statistics
Abstract
Weak-lensing searches for galaxy clusters are plagued by low completeness and purity, severely limiting their usefulness for constraining cosmological parameters with the cluster mass function. A significant fraction of `false positives' are due to projection of large-scale structure and as such carry information about the matter distribution. We demonstrate that by constructing a "peak function", in analogy to the cluster mass function, cosmological parameters can be constrained. To this end we carried out a large number of cosmological N-body simulations in the \Omega_m-\sigma_8 plane to study the variation of this peak function. We demonstrate that the peak statistics is able to provide constraints competitive with those obtained from cosmic-shear tomography from the same data set. By taking the full cross-covariance between the peak statistics and cosmic shear into account, we show that the combination of both methods leads to tighter constraints than either method alone can provide.
Keywords
Cite
@article{arxiv.0906.3512,
title = {Cosmology with the shear-peak statistics},
author = {J. P. Dietrich and J. Hartlap},
journal= {arXiv preprint arXiv:0906.3512},
year = {2015}
}
Comments
11 pages, 6 figures, accepted for publication in MNRAS. Minor changes to description of N-body and ray-tracing simulations