Cosmological constraints from the convergence 1-point probability distribution
Abstract
We examine the cosmological information available from the 1-point probability density function (PDF) of the weak-lensing convergence field, utilizing fast L-PICOLA simulations and a Fisher analysis. We find competitive constraints in the Ωm-σ8 plane from the convergence PDF with 188 arcmin2 pixels compared to the cosmic shear power spectrum with an equivalent number of modes (ℓ < 886). The convergence PDF also partially breaks the degeneracy cosmic shear exhibits in that parameter space. A joint analysis of the convergence PDF and shear 2-point function also reduces the impact of shape measurement systematics, to which the PDF is less susceptible, and improves the total figure of merit by a factor of 2-3, depending on the level of systematics. Finally, we present a correction factor necessary for calculating the unbiased Fisher information from finite differences using a limited number of cosmological simulations.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- November 2017
- DOI:
- 10.1093/mnras/stx1626
- arXiv:
- arXiv:1611.01486
- Bibcode:
- 2017MNRAS.472..439P
- Keywords:
-
- gravitational lensing: weak;
- cosmological parameters;
- large-scale structure of Universe;
- cosmology: observations;
- Astrophysics - Cosmology and Nongalactic Astrophysics
- E-Print:
- 10 pages, 5 figures