skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Cosmology from cosmic shear with Dark Energy Survey Science Verification data

Abstract

We present the first constraints on cosmology from the Dark Energy Survey (DES), using weak lensing measurements from the preliminary Science Verification (SV) data. We use 139 square degrees of SV data, which is less than 3% of the full DES survey area. Using cosmic shear 2-point measurements over three redshift bins we find σ 8(m=0.3) 0.5 = 0:81 ± 0:06 (68% confidence), after marginalising over 7 systematics parameters and 3 other cosmological parameters. Furthermore, we examine the robustness of our results to the choice of data vector and systematics assumed, and find them to be stable. About 20% of our error bar comes from marginalising over shear and photometric redshift calibration uncertainties. The current state-of-the-art cosmic shear measurements from CFHTLenS are mildly discrepant with the cosmological constraints from Planck CMB data. Our results are consistent with both datasets. Our uncertainties are ~30% larger than those from CFHTLenS when we carry out a comparable analysis of the two datasets, which we attribute largely to the lower number density of our shear catalogue. We investigate constraints on dark energy and find that, with this small fraction of the full survey, the DES SV constraints make negligible impact on the Planck constraints.more » The moderate disagreement between the CFHTLenS and Planck values of σ 8m=0.3) 0.5 is present regardless of the value of w.« less

Authors:
 [1]
  1. et al.
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Brookhaven National Laboratory (BNL), Upton, NY (United States); SLAC National Accelerator Lab., Menlo Park, CA (United States); Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25); National Science Foundation (NSF); German Research Foundation (DFG)
OSTI Identifier:
1223233
Report Number(s):
DES-2015-0076; FERMILAB-PUB-15-285-AE; arXiv:1507.05552; BNL-112621-2016-JA
Journal ID: ISSN 2470-0010; PRVDAQ; 1383855
Grant/Contract Number:
AC02-07CH11359; FERMILAB-PUB-15-285-AE; AC02-98CH10886; SC0007901; FG02-91ER40690; SC00112704; AC02-06CH11357
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Physical Review D
Additional Journal Information:
Journal Volume: 94; Journal Issue: 2; Journal ID: ISSN 2470-0010
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
79 ASTRONOMY AND ASTROPHYSICS; cosmology: observations; cosmological parameters; gravitational lensing: weak; dark matter; dark energy; large-scale structure of Universe

Citation Formats

Becker, M. R. Cosmology from cosmic shear with Dark Energy Survey Science Verification data. United States: N. p., 2016. Web. doi:10.1103/PhysRevD.94.022001.
Becker, M. R. Cosmology from cosmic shear with Dark Energy Survey Science Verification data. United States. doi:10.1103/PhysRevD.94.022001.
Becker, M. R. 2016. "Cosmology from cosmic shear with Dark Energy Survey Science Verification data". United States. doi:10.1103/PhysRevD.94.022001. https://www.osti.gov/servlets/purl/1223233.
@article{osti_1223233,
title = {Cosmology from cosmic shear with Dark Energy Survey Science Verification data},
author = {Becker, M. R.},
abstractNote = {We present the first constraints on cosmology from the Dark Energy Survey (DES), using weak lensing measurements from the preliminary Science Verification (SV) data. We use 139 square degrees of SV data, which is less than 3% of the full DES survey area. Using cosmic shear 2-point measurements over three redshift bins we find σ8(m=0.3)0.5 = 0:81 ± 0:06 (68% confidence), after marginalising over 7 systematics parameters and 3 other cosmological parameters. Furthermore, we examine the robustness of our results to the choice of data vector and systematics assumed, and find them to be stable. About 20% of our error bar comes from marginalising over shear and photometric redshift calibration uncertainties. The current state-of-the-art cosmic shear measurements from CFHTLenS are mildly discrepant with the cosmological constraints from Planck CMB data. Our results are consistent with both datasets. Our uncertainties are ~30% larger than those from CFHTLenS when we carry out a comparable analysis of the two datasets, which we attribute largely to the lower number density of our shear catalogue. We investigate constraints on dark energy and find that, with this small fraction of the full survey, the DES SV constraints make negligible impact on the Planck constraints. The moderate disagreement between the CFHTLenS and Planck values of σ8(Ωm=0.3)0.5 is present regardless of the value of w.},
doi = {10.1103/PhysRevD.94.022001},
journal = {Physical Review D},
number = 2,
volume = 94,
place = {United States},
year = 2016,
month = 7
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 15works
Citation information provided by
Web of Science

Save / Share:
  • Here, we present the first constraints on cosmology from the Dark Energy Survey (DES), using weak lensing measurements from the preliminary Science Verification (SV) data. We use 139 square degrees of SV data, which is less than 3% of the full DES survey area. Using cosmic shear 2-point measurements over three redshift bins we find σ 8m/0.3) 0.5 = 0.81 ± 0.06 (68% confidence), after marginalizing over 7 systematics parameters and 3 other cosmological parameters. We examine the robustness of our results to the choice of data vector and systematics assumed, and find them to be stable. About 20%more » of our error bar comes from marginalizing over shear and photometric redshift calibration uncertainties. The current state-of-the-art cosmic shear measurements from CFHTLenS are mildly discrepant with the cosmological constraints from Planck CMB data; our results are consistent with both data sets. Our uncertainties are ~30% larger than those from CFHTLenS when we carry out a comparable analysis of the two data sets, which we attribute largely to the lower number density of our shear catalogue. We investigate constraints on dark energy and find that, with this small fraction of the full survey, the DES SV constraints make negligible impact on the Planck constraints. The moderate disagreement between the CFHTLenS and Planck values of σ 8m/0.3) 0.5 is present regardless of the value of w.« less
  • Cited by 15
  • Here, we present the first constraints on cosmology from the Dark Energy Survey (DES), using weak lensing measurements from the preliminary Science Verification (SV) data. We use 139 square degrees of SV data, which is less than 3% of the full DES survey area. Using cosmic shear 2-point measurements over three redshift bins we find σ 8m/0.3) 0.5=0.81±0.06 (68% confidence), after marginalizing over 7 systematics parameters and 3 other cosmological parameters. We examine the robustness of our results to the choice of data vector and systematics assumed, and find them to be stable. About 20% of our error barmore » comes from marginalizing over shear and photometric redshift calibration uncertainties. The current state-of-the-art cosmic shear measurements from CFHTLenS are mildly discrepant with the cosmological constraints from Planck CMB data; our results are consistent with both data sets. Our uncertainties are ~30% larger than those from CFHTLenS when we carry out a comparable analysis of the two data sets, which we attribute largely to the lower number density of our shear catalogue. We also investigate constraints on dark energy and find that, with this small fraction of the full survey, the DES SV constraints make negligible impact on the Planck constraints. Finally, the moderate disagreement between the CFHTLenS and Planck values of σ 8m/0.3) 0.5 is present regardless of the value of w.« less
  • Shear peak statistics has gained a lot of attention recently as a practical alternative to the two point statistics for constraining cosmological parameters. We perform a shear peak statistics analysis of the Dark Energy Survey (DES) Science Verification (SV) data, using weak gravitational lensing measurements from a 139 degmore » $^2$ field. We measure the abundance of peaks identified in aperture mass maps, as a function of their signal-to-noise ratio, in the signal-to-noise range $$0<\mathcal S / \mathcal N<4$$. To predict the peak counts as a function of cosmological parameters we use a suite of $N$-body simulations spanning 158 models with varying $$\Omega_{\rm m}$$ and $$\sigma_8$$, fixing $w = -1$, $$\Omega_{\rm b} = 0.04$$, $h = 0.7$ and $$n_s=1$$, to which we have applied the DES SV mask and redshift distribution. In our fiducial analysis we measure $$\sigma_{8}(\Omega_{\rm m}/0.3)^{0.6}=0.77 \pm 0.07$$, after marginalising over the shear multiplicative bias and the error on the mean redshift of the galaxy sample. We introduce models of intrinsic alignments, blending, and source contamination by cluster members. These models indicate that peaks with $$\mathcal S / \mathcal N>4$$ would require significant corrections, which is why we do not include them in our analysis. We compare our results to the cosmological constraints from the two point analysis on the SV field and find them to be in good agreement in both the central value and its uncertainty. As a result, we discuss prospects for future peak statistics analysis with upcoming DES data.« less
  • Shear peak statistics has gained a lot of attention recently as a practical alternative to the two point statistics for constraining cosmological parameters. We perform a shear peak statistics analysis of the Dark Energy Survey (DES) Science Verification (SV) data, using weak gravitational lensing measurements from a 139 degmore » $^2$ field. We measure the abundance of peaks identified in aperture mass maps, as a function of their signal-to-noise ratio, in the signal-to-noise range $$0<\mathcal S / \mathcal N<4$$. To predict the peak counts as a function of cosmological parameters we use a suite of $N$-body simulations spanning 158 models with varying $$\Omega_{\rm m}$$ and $$\sigma_8$$, fixing $w = -1$, $$\Omega_{\rm b} = 0.04$$, $h = 0.7$ and $$n_s=1$$, to which we have applied the DES SV mask and redshift distribution. In our fiducial analysis we measure $$\sigma_{8}(\Omega_{\rm m}/0.3)^{0.6}=0.77 \pm 0.07$$, after marginalising over the shear multiplicative bias and the error on the mean redshift of the galaxy sample. We introduce models of intrinsic alignments, blending, and source contamination by cluster members. These models indicate that peaks with $$\mathcal S / \mathcal N>4$$ would require significant corrections, which is why we do not include them in our analysis. We compare our results to the cosmological constraints from the two point analysis on the SV field and find them to be in good agreement in both the central value and its uncertainty. As a result, we discuss prospects for future peak statistics analysis with upcoming DES data.« less