KiDS-1000 Cosmology: Multi-probe weak gravitational lensing and spectroscopic galaxy clustering constraints
Creators: name: Heymans, Catherine
name: Tröster, Tilman
name: Asgari, Marika
name: Blake, Chris
name: Hildebrandt, Hendrik
name: Joachimi, Benjamin
name: Kuijken, Konrad
name: Lin, Chieh-An
name: Sánchez, Ariel G.
name: Busch, Jan Luca van den
name: Wright, Angus H.
name: Amon, Alexandra
name: Bilicki, Maciej
name: de Jong, Jelte
name: Crocce, Martin
name: Dvornik, Andrej
name: Erben, Thomas
name: Fortuna, Maria Cristina
name: Getman, Fedor
name: Giblin, Benjamin
name: Glazebrook, Karl
name: Hoekstra, Henk
name: Joudaki, Shahab
name: Kannawadi, Arun
name: Köhlinger, Fabian
name: Lidman, Chris
name: Miller, Lance
name: Napolitano, Nicola R.
name: Parkinson, David
name: Schneider, Peter
name: Shan, HuanYuan
name: Valentijn, Edwin
name: Kleijn, Gijs Verdoes
name: Wolf, Christian
Publisher: name: arXiv
Year: 2020
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: We present a joint cosmological analysis of weak gravitational lensing observations from the Kilo-Degree Survey (KiDS-1000), with redshift-space galaxy clustering observations from the Baryon Oscillation Spectroscopic Survey (BOSS), and galaxy-galaxy lensing observations from the overlap between KiDS-1000, BOSS and the spectroscopic 2-degree Field Lensing Survey (2dFLenS). This combination of large-scale structure probes breaks the degeneracies between cosmological parameters for individual observables, resulting in a constraint on the structure growth parameter $S_8=σ_8 \sqrt{Ω_{\rm m}/0.3} = 0.766^{+0.020}_{-0.014}$, that has the same overall precision as that reported by the full-sky cosmic microwave background observations from Planck. The recovered $S_8$ amplitude is low, however, by $8.3 \pm 2.6$ % relative to Planck. This result builds from a series of KiDS-1000 analyses where we validate our methodology with variable depth mock galaxy surveys, our lensing calibration with image simulations and null-tests, and our optical-to-near-infrared redshift calibration with multi-band mock catalogues and a spectroscopic-photometric clustering analysis. The systematic uncertainties identified by these analyses are folded through as nuisance parameters in our cosmological analysis. Inspecting the offset between the marginalised posterior distributions, we find that the $S_8$-difference with Planck is driven by a tension in the matter fluctuation amplitude parameter, $σ_8$. We quantify the level of agreement between the CMB and our large-scale structure constraints using a series of different metrics, finding differences with a significance ranging between $\sim\! 3\,σ$, when considering the offset in $S_{8}$, and $\sim\! 2\,σ$, when considering the full multi-dimensional parameter space.
description: 25 pages, 11 figures, 5 tables, A&amp;A accepted, including a new appendix on Intrinsic Alignments. The KiDS-1000 data products are available for download at http://kids.strw.leidenuniv.nl/DR4/lensing.php. This data release includes open source software, the shear-photo-z catalogue, the cosmic shear and 3x2pt data vectors and covariances, and posteriors in the form of Multinest chains