Abbott, T;
Abdalla, FB;
Allam, S;
Amara, A;
Annis, J;
Armstrong, R;
Bacon, D;
... Zuntz, J; + view all
(2016)
Cosmology from cosmic shear with Dark Energy Survey Science Verification data.
Physical Review D
, 94
(2)
, Article 022001. 10.1103/PhysRevD.94.022001.
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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 ( Ω m / 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 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 8 ( Ω m / 0.3 ) 0.5 is present regardless of the value of w .
Type: | Article |
---|---|
Title: | Cosmology from cosmic shear with Dark Energy Survey Science Verification data |
Open access status: | An open access version is available from UCL Discovery |
DOI: | 10.1103/PhysRevD.94.022001 |
Publisher version: | http://doi.org/10.1103/PhysRevD.94.022001 |
Language: | English |
Additional information: | © 2016 American Physical Society |
Keywords: | Science & Technology, Physical Sciences, Astronomy & Astrophysics, Physics, Particles & Fields, Physics, MATTER POWER SPECTRUM, WEAK-LENSING TOMOGRAPHY, LARGE-SCALE STRUCTURE, BARYON ACOUSTIC-OSCILLATIONS, INTRINSIC ALIGNMENTS, PARAMETER CONSTRAINTS, GALAXY ELLIPTICITIES, PRECISION COSMOLOGY, COVARIANCE-MATRIX, HUBBLE CONSTANT |
UCL classification: | UCL UCL > Provost and Vice Provost Offices > UCL BEAMS UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Maths and Physical Sciences > Dept of Physics and Astronomy |
URI: | https://discovery.ucl.ac.uk/id/eprint/1504353 |
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