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

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 moderatemore » disagreement between the CFHTLenS and Planck values of σ8m=0.3)0.5 is present regardless of the value of w.« less
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Publication Date:
OSTI Identifier:
Report Number(s):
FERMILAB-PUB--15-285-AE; DES--2015-0076
Journal ID: ISSN 2470-0010; PRVDAQ; arXiv eprint number arXiv:1507.05552
DOE Contract Number:
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review D; Journal Volume: 94; Journal Issue: 2
American Physical Society (APS)
Research Org:
Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
Sponsoring Org:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Contributing Orgs:
The Dark Energy Survey (DES) Collaboration
Country of Publication:
United States
79 ASTRONOMY AND ASTROPHYSICS cosmology:observations; cosmological parameters; gravitational lensing: weak; dark matter; dark energy; large-scale structure of Universe