Cosmological constraints from the convergence 1-point probability distribution

• Published in: Monthly notices of the Royal Astronomical Society Vol. 472; no. 1; pp. 439 - 446
• Main Authors: Patton, Kenneth, Blazek, Jonathan, Honscheid, Klaus, Huff, Eric, Melchior, Peter, Ross, Ashley J., Suchyta, Eric
• Format: Journal Article
• Language: English
• Published: United States Oxford University Press 01.11.2017; Royal Astronomical Society
• Subjects: ASTRONOMY AND ASTROPHYSICS; cosmology: observations; gravitational lensing: weak; cosmological parameters; large-scale structure of Universe
• ISSN: 0035-8711; 1365-2966
• DOI: 10.1093/mnras/stx1626

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 Ω m –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.