TY - JOUR
T1 - KiDS+GAMA
T2 - Cosmology constraints from a joint analysis of cosmic shear, galaxy-galaxy lensing, and angular clustering
AU - van Uitert, Edo
AU - Joachimi, Benjamin
AU - Joudaki, Shahab
AU - Amon, Alexandra
AU - Heymans, Catherine
AU - Köhlinger, Fabian
AU - Asgari, Marika
AU - Blake, Chris
AU - Choi, Ami
AU - Erben, Thomas
AU - Farrow, Daniel J.
AU - Harnois-Déraps, Joachim
AU - Hildebrandt, Hendrik
AU - Hoekstra, Henk
AU - Kitching, Thomas D.
AU - Klaes, Dominik
AU - Kuijken, Konrad
AU - Merten, Julian
AU - Miller, Lance
AU - Nakajima, Reiko
AU - Schneider, Peter
AU - Valentijn, Edwin
AU - Viola, Massimo
N1 - Publisher Copyright:
© 2018 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society.
PY - 2018/6/1
Y1 - 2018/6/1
N2 - We present cosmological parameter constraints from a joint analysis of three cosmological probes: the tomographic cosmic shear signal in~450 deg2 of data from the Kilo Degree Survey (KiDS), the galaxy-matter cross-correlation signal of galaxies from the Galaxies And Mass Assembly (GAMA) survey determined with KiDS weak lensing, and the angular correlation function of the same GAMA galaxies. We use fast power spectrum estimators that are based on simple integrals over the real-space correlation functions, and show that they are practically unbiased over relevant angular frequency ranges. We test our full pipeline on numerical simulations that are tailored to KiDS and retrieve the input cosmology. By fitting different combinations of power spectra, we demonstrate that the three probes are internally consistent. For all probes combined, we obtain S8 ≡ σ8 √ Ωm/0.3 = 0.800-0.027+0.029, consistent with Planck and the fiducial KiDS-450 cosmic shear correlation function results. Marginalizing over wide priors on the mean of the tomographic redshift distributions yields consistent results for S8 with an increase of 28 per cent in the error. The combination of probes results in a 26 per cent reduction in uncertainties of S8 over using the cosmic shear power spectra alone. The main gain from these additional probes comes through their constraining power on nuisance parameters, such as the galaxy intrinsic alignment amplitude or potential shifts in the redshift distributions, which are up to a factor of 2 better constrained compared to using cosmic shear alone, demonstrating the value of large-scale structure probe combination.
AB - We present cosmological parameter constraints from a joint analysis of three cosmological probes: the tomographic cosmic shear signal in~450 deg2 of data from the Kilo Degree Survey (KiDS), the galaxy-matter cross-correlation signal of galaxies from the Galaxies And Mass Assembly (GAMA) survey determined with KiDS weak lensing, and the angular correlation function of the same GAMA galaxies. We use fast power spectrum estimators that are based on simple integrals over the real-space correlation functions, and show that they are practically unbiased over relevant angular frequency ranges. We test our full pipeline on numerical simulations that are tailored to KiDS and retrieve the input cosmology. By fitting different combinations of power spectra, we demonstrate that the three probes are internally consistent. For all probes combined, we obtain S8 ≡ σ8 √ Ωm/0.3 = 0.800-0.027+0.029, consistent with Planck and the fiducial KiDS-450 cosmic shear correlation function results. Marginalizing over wide priors on the mean of the tomographic redshift distributions yields consistent results for S8 with an increase of 28 per cent in the error. The combination of probes results in a 26 per cent reduction in uncertainties of S8 over using the cosmic shear power spectra alone. The main gain from these additional probes comes through their constraining power on nuisance parameters, such as the galaxy intrinsic alignment amplitude or potential shifts in the redshift distributions, which are up to a factor of 2 better constrained compared to using cosmic shear alone, demonstrating the value of large-scale structure probe combination.
KW - Large-scale structure of Universe
KW - Methods: data analysis
KW - Methods: statistical
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U2 - 10.1093/mnras/sty551
DO - 10.1093/mnras/sty551
M3 - Article
AN - SCOPUS:85045443752
SN - 0035-8711
VL - 476
SP - 4662
EP - 4689
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
IS - 4
ER -