CFHTLenS revisited: assessing concordance with Planck including astrophysical systematics

By S. Joudaki, C. Blake, Catherine Heymans, A. Choi, J. Harnois-Déraps, H. Hildebrandt, B. Joachimi, Andrew Johnson, A. Mead, David Parkinson and 2 more. 2016

204 citations recorded by the source corpus.

We investigate the impact of astrophysical systematics on cosmic shear cosmological parameter constraints from the Canada–France–Hawaii Telescope Lensing Survey (CFHTLenS) and the concordance with cosmic microwave background measurements by Planck. We present updated CFHTLenS cosmic shear tomography measurements extended to degree scales using a covariance calibrated by a new suite of N-body simulations. We analyse these measurements with a new model fitting pipeline, accounting for key systematic uncertainties arising from intrinsic galaxy alignments, baryonic effects in the non-linear matter power spectrum, and photometric redshift uncertainties. We examine the impact of the systematic degrees of freedom on the cosmological parameter constraints, both independently and jointly. When the systematic uncertainties are considered independently, the intrinsic alignment amplitude is the only degree of freedom that is substantially preferred by the data. When the systematic uncertainties are considered jointly, there is no consistently strong preference in favour of the more complex models. We quantify the level of concordance between the CFHTLenS and Planck data sets by employing two distinct data concordance tests, grounded in Bayesian evidence and information theory. We find that the two data concordance tests largely agree with one another and that the level of concordance between the CFHTLenS and Planck data sets is sensitive to the exact details of the systematic uncertainties included in our analysis, ranging from decisive discordance to substantial concordance as the treatment of the systematic uncertainties becomes more conservative. The least conservative scenario is the one most favoured by the cosmic shear data, but it is also the one that shows the greatest degree of discordance with Planck. The data and analysis code are publicly available at https://github.com/sjoudaki/cfhtlens_revisited.

Subfields: Astronomy and Astrophysics, Nuclear and High Energy Physics

View Paper: https://www.semanticscholar.org/paper/d88165efd054f26a80af71ec5e831a19df2cbf04

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Citations in the corpus

Tale of stable interacting dark energy, observational signatures, and the H0 tension (2018, background): “It is furthermore interesting to examine how σ8 shifts, in order to investigate if the IDE could alleviate the tension at more than 2σ present between the CMB and the weak lensing measurements from the CFHTLenS survey [92, 93, 124] and KiDS-450 [94].”
KiDS-450 + 2dFLenS: Cosmological parameter constraints from weak gravitational lensing tomography and overlapping redshift-space galaxy clustering (2017, methodology): “…we have developed a self-consistent Markov Chain Monte Carlo (MCMC) fitting pipeline in COSMOMC (Lewis & Bridle 2002), which is an extension of the pipeline used in the cosmic shear analyses of CFHTLenS (Joudaki et al. 2017a) and KiDS-450 (Hildebrandt et al. 2017; Joudaki et al. 2017b).”
Alleviating the H0 and σ8 anomalies with a decaying dark matter model (2019, result): “The CFHTLenS weak-lensing survey also finds support for disagreement with Planck CMB predictions [14].”
PICO: Probe of Inflation and Cosmic Origins (2019, background): “6σ discrepancy between the CMB- and local-Universe-anchored supernovaebased measurements of the Hubble constant [37, 132]; the identification of lack of correlations at large angles in the T T power spectrum that has an apparent probability of less than 10−3 of occurrence in standard ΛCDM [133]; and”
Elucidating ΛCDM: Impact of Baryon Acoustic Oscillation Measurements on the Hubble Constant Discrepancy (2017, methodology): “…between the Planck predictions for the growth of cosmic structure (through the matter density, Ωm, and present-day density fluctuation amplitude, σ8) and measurements using weak gravitational lensing (e.g., Hildebrandt et al. 2017; Joudaki et al. 2017; Alsing et al. 2017; Köhlinger et al. 2017).”
A volumetric deep Convolutional Neural Network for simulation of dark matter halo catalogues (2018, background): “Modern large-scale structure survey techniques like Sunaeyev-Zeldovich effect (Planck Collaboration et al. 2016; George et al. 2015), weak lensing (Ade et al. 2016; Joudaki et al. 2017; Hildebrandt et al. 2017; DES Collaboration et al. 2017), or intensity mapping (Kovetz et al. 2017), hold in- ?”
KiDS+VIKING-450 and DES-Y1 combined: Cosmology with cosmic shear (2019, background): “Using the logI statistic (Joudaki et al. 2017) and Jeffreys’ scale (Jeffreys 1961; Kass & Raftery 1995), we find that KV450 and DES-Y1 are in ‘strong’ concordance (logI = 1.4), which is an expected outcome given the S 8 agreement between the two surveys.”
KiDS+VIKING-450: Cosmic shear tomography with optical and infrared data (2018, methodology): “This episode illustrates that our analysis was never blind against the values of Ωm and σ8, whose values are also affected by our prior choices (for a detailed discussion of this effect see Joudaki et al. 2017a).”
Cosmology from cosmic shear power spectra with Subaru Hyper Suprime-Cam first-year data (2018, methodology): “…from the KiDS-450 correlation function analysis (Hildebrandt et al. 2017), 0.651± 0.058 from the KiDS-450 power spectrum analysis (Köhlinger et al. 2017), 0.732+0.029−0.031 from CFHTLenS (Joudaki et al. 2017), and 0.782+0.027−0.027 from DES year one (Y1) data (Troxel et al. 2017).”
KiDS-450: testing extensions to the standard cosmological model (2016, methodology): “The extended cosmology does not improve the goodness of fit noticeably as compared to CDM (with χ2eff ≈ −1 for KiDS and χ2eff ≈ 0 for Planck), and is not favoured by the KiDS and Planck data sets (with DIC 1 for KiDS and Planck).”