The cross-correlation between 3d cosmic shear and the integrated Sachs-Wolfe effect
Abstract
We present the first calculation of the cross-correlation between three-dimensional cosmic shear and the integrated Sachs-Wolfe (iSW) effect. Both signals are combined in a single formalism, which permits the computation of the full covariance matrix. In order to avoid the uncertainties presented by the non-linear evolution of the matter power spectrum and intrinsic alignments of galaxies, our analysis is restricted to large scales, i.e. multipoles below l=1000. We demonstrate in a Fisher analysis that this reduction compared to other studies of three-dimensional weak lensing extending to smaller scales is compensated by the information that is gained if the additional iSW signal and in particular its cross-correlation with lensing data are considered. Given the observational standards of upcoming weak lensing surveys like Euclid, marginal errors on cosmological parameters decrease by ten per cent compared to a cosmic shear experiment if both types of information are combined without a CMB prior. Once the constraining power of CMB data is added, the improvement becomes marginal.
Cite
@article{arxiv.1603.06406,
title = {The cross-correlation between 3d cosmic shear and the integrated Sachs-Wolfe effect},
author = {Britta Zieser and Philipp M. Merkel},
journal= {arXiv preprint arXiv:1603.06406},
year = {2016}
}
Comments
10 pages, 6 figures; accepted for publication in MNRAS