Year: 2019
Type: article
Abstract: We present a tomographic cosmic shear analysis of the Kilo-Degree Survey (KiDS) combined with the VISTA Kilo-Degree Infrared Galaxy Survey. This is the first time that a full optical to near-infrared data set has been used for a wide-field cosmological weak lensing experiment. This unprecedented data, spanning 450 deg2, allows us to significantly improve the estimation of photometric redshifts, such that we are able to include robustly higher-redshift sources for the lensing measurement, and – most importantly – to solidify our knowledge of the redshift distributions of the sources. Based on a flat ΛCDM model we findS8≡ σ8Ωm/0.3 = 0.737+0.040−0.036in a blind analysis from cosmic shear alone. The tension between KiDS cosmic shear and the Planck-Legacy CMB measurements remains in this systematically more robust analysis, withS8differing by 2.3σ. This result is insensitive to changes in the priors on nuisance parameters for intrinsic alignment, baryon feedback, and neutrino mass. KiDS shear measurements are calibrated with a new, more realistic set of image simulations and no significant B-modes are detected in the survey, indicating that systematic errors are under control. When calibrating our redshift distributions by assuming the 30-band COSMOS-2015 photometric redshifts are correct (following the Dark Energy Survey and the Hyper Suprime-Cam Survey), we find the tension withPlanckis alleviated. The robust determination of source redshift distributions remains one of the most challenging aspects for future cosmic shear surveys.
Source: Astronomy and Astrophysics
Authors: H. Hildebrandt, F. Köhlinger, J. L. van den Busch, B. Joachimi, C. Heymans, A. Kannawadi, A. H. Wright, M. Asgari, C. Blake, H. Hoekstra, S. Joudaki, K. Kuijken, L. Miller, C. B. Morrison, T. Tröster, A. Amon, M. Archidiacono, S. Brieden, A. Choi, J. T. A. de Jong, T. Erben, B. Giblin, A. Mead, J. A. Peacock, M. Radovich, P. Schneider, C. Sifón, M. Tewes
Institutions: University of Bonn, Ruhr University Bochum, Kavli Institute for the Physics and Mathematics of the Universe, The University of Tokyo, University College London, Royal Observatory, University of Edinburgh, Leiden University, Leiden Observatory, Swinburne University of Technology, University of Oxford, University of Washington, RWTH Aachen University, Universitat de Barcelona, The Ohio State University, University of Groningen, University of British Columbia, Osservatorio Astronomico di Padova, Pontificia Universidad Católica de Valparaíso, Princeton University
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $1,680
Funders: National Science Foundation, National Aeronautics and Space Administration, Alexander von Humboldt-Stiftung, Aspen Center for Physics, Deutsche Forschungsgemeinschaft, Ministry of Education, Culture, Sports, Science and Technology, Bundesministerium für Bildung und Forschung, Nederlandse Organisatie voor Wetenschappelijk Onderzoek, Max-Planck-Gesellschaft, Institute for Data Intensive Research in Astrophysics and Cosmology, University of Washington, Science and Technology Facilities Council, SLAC National Accelerator Laboratory
Awards: G1259507762, G1396063042, G145016332, G1541806023, G165597396, G1736745720, G1771230537, G198410584, G2073976794, Final Design, Construction and Operations of Vera C. Rubin Observatory, G2229954460, G2240879383, G2264732632, G2311867446, G2432923657, G262532246, G2684751754, G2840404975, G3156532051, The DiRAC 2.5x Facility, Turning galaxy alignments into cosmological weighing scales, G3531124447, G3563244976, G3718830055, G4135703890, G4235786860, G4369834866, G4598327346, G4654690619, G4711507462, G4767683273, G5178825541, G5562923697, G5660267321, G5768834005, G588734541, G6181174915, G6216976133, G6537386148, G6802598382, G6823224962, G6865164750, G6926846737, Astrophysics at Oxford 2016-2019, G7108246583, DiRAC2: 100 Tflop/s HPC cluster procurement, G7521014512, G7573294876, Programs on Critical Problems in Physics, Astrophysics and Biophysics at the Aspen Center for Physics, G7937591081, G8050714359, G8271379602, G8345931481, G8551812566, G8710138095, G8710606730, G8726098666, G878803593, DiRAC 2.5 Operations 2017-2020
OpenAlex ID: W2904800511