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Title: Cosmological constraints from the convergence 1-point probability distribution

Abstract

Here, 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 arcmin 2 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.

Authors:
 [1];  [2];  [1];  [3]; ORCiD logo [4]; ORCiD logo [1]; ORCiD logo [5]
  1. The Ohio State Univ., Columbus, OH (United States)
  2. The Ohio State Univ., Columbus, OH (United States); Ecole Polytechnique Federale de Lausanne (EPFL), Versoix (Switzerland)
  3. The Ohio State Univ., Columbus, OH (United States); California Inst. of Technology (CalTech), Pasadena, CA (United States)
  4. Princeton Univ., Princeton, NJ (United States)
  5. The Ohio State Univ., Columbus, OH (United States); Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Advanced Scientific Computing Research (ASCR) (SC-21)
OSTI Identifier:
1410195
DOE Contract Number:
AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Monthly Notices of the Royal Astronomical Society; Journal Volume: 472; Journal Issue: 1
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS

Citation Formats

Patton, Kenneth, Blazek, Jonathan, Honscheid, Klaus, Huff, Eric, Melchior, Peter, Ross, Ashley J., and Suchyta, Eric D.. Cosmological constraints from the convergence 1-point probability distribution. United States: N. p., 2017. Web. doi:10.1093/mnras/stx1626.
Patton, Kenneth, Blazek, Jonathan, Honscheid, Klaus, Huff, Eric, Melchior, Peter, Ross, Ashley J., & Suchyta, Eric D.. Cosmological constraints from the convergence 1-point probability distribution. United States. doi:10.1093/mnras/stx1626.
Patton, Kenneth, Blazek, Jonathan, Honscheid, Klaus, Huff, Eric, Melchior, Peter, Ross, Ashley J., and Suchyta, Eric D.. Thu . "Cosmological constraints from the convergence 1-point probability distribution". United States. doi:10.1093/mnras/stx1626.
@article{osti_1410195,
title = {Cosmological constraints from the convergence 1-point probability distribution},
author = {Patton, Kenneth and Blazek, Jonathan and Honscheid, Klaus and Huff, Eric and Melchior, Peter and Ross, Ashley J. and Suchyta, Eric D.},
abstractNote = {Here, 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.},
doi = {10.1093/mnras/stx1626},
journal = {Monthly Notices of the Royal Astronomical Society},
number = 1,
volume = 472,
place = {United States},
year = {Thu Jun 29 00:00:00 EDT 2017},
month = {Thu Jun 29 00:00:00 EDT 2017}
}
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