Cosmology from cosmic shear with Dark Energy Survey science verification data

By The Dark Energy Survey Collaboration, T. Abbott, Filipe B. Abdalla, Sahar Allam, Adam Amara, James Annis, R. Armstrong, D. Bacon, M. Banerji, A. Bauer and 119 more. 2015

147 citations recorded by the source corpus.

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 sigma8(Omegam/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 sigma8(Omegam/0.3 )0.5 is present regardless of the value of w .

Subfields: Astronomy and Astrophysics

View Paper: https://www.semanticscholar.org/paper/a0f0a1fc7a06c6bcb30b2a2a89d52b7a7ac9c7c0

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Citations in the corpus

KiDS-450: cosmological parameter constraints from tomographic weak gravitational lensing (2016, methodology): “…relies on the assumption that small-scale systematics behave similarly to largescale systematics as the B-mode band-power measurement does not probe the same angular scales as the primary ξ± cosmic shear statistic which is then used for cosmological parameter estimation (Abbott et al. 2016).”
Cosmology from cosmic shear power spectra with Subaru Hyper Suprime-Cam first-year data (2018, methodology): “This phenomenological model has been found to fit the galaxy-shear cross correlations down to >∼ 1− 2h−1Mpc quite well (Singh et al. 2015; Blazek et al. 2015), and has been used in various cosmic shear analyses (Heymans et al. 2013; Kitching et al. 2014; Abbott et al. 2016; Hildebrandt et al. 2017).”
The first-year shear catalog of the Subaru Hyper Suprime-Cam Subaru Strategic Program Survey (2017, methodology): “To avoid scales which could be affected by either baryonic effects or theoretical uncertainties in the matter power spectrum, we use ξ+ and ξ− measurements on scales θ > 4 and > 40 arcminutes, respectively (Abbott et al. 2016).”
KiDS-450 + 2dFLenS: Cosmological parameter constraints from weak gravitational lensing tomography and overlapping redshift-space galaxy clustering (2017, result): “While CFHTLenS and KiDS are concordant with pre-Planck CMB surveys (Calabrese et al. 2013, 2017; Hinshaw et al. 2013), cosmic shear measurements by the Deep Lens Survey (DLS; Jee et al. 2016) and the Dark Energy Survey (DES; Abbott et al. 2016) show greater degrees of concordance with Planck.”