UNIONS: The impact of systematic errors on weak-lensing peak counts

Abstract

UNIONS is an ongoing deep photometric multi-band survey of the Northern sky. As part of UNIONS, CFIS provides r-band data which we use to study weak-lensing peak counts for cosmological inference. We assess systematic effects for weak-lensing peak counts and their impact on cosmological parameters for the UNIONS survey. In particular, we present results on local calibration, metacalibration shear bias, baryonic feedback, the source galaxy redshift estimate, intrinsic alignment, and the cluster member dilution. For each uncertainty and systematic effect, we describe our mitigation scheme and the impact on cosmological parameter constraints. We obtain constraints on cosmological parameters from MCMC using CFIS data and MassiveNuS N-body simulations as a model for peak counts statistics. Depending on the calibration (local versus global, and the inclusion of the residual multiplicative shear bias), the mean matter density parameter ${\Omega }_m$ can shift up to $-0.024$ ($-0.5\sigma$). We also see that including baryonic corrections can shift ${\Omega }_m$ by $+0.027$ ($+0.5\sigma$) with respect to the DM-only simulations. Reducing the impact of the intrinsic alignment and cluster member dilution through signal-to-noise cuts can lead to a shift in ${\Omega }_m$ of $+0.027$ ($+0.5\sigma$). Finally, with a mean redshift uncertainty of $\Delta \bar{z}=0.03$, we see that the shift of ${\Omega }_m$ ($+0.001$ which corresponds to $+0.02\sigma$) is not significant. This paper investigates for the first time with UNIONS weak-lensing data and peak counts the impact of systematic effects. The value of ${\Omega }_m$ is the most impacted and can shift up to $\sim 0.03$ which corresponds to $0.5\sigma$ depending on the choices for each systematics. We expect constraints to become more reliable with future (larger) data catalogues, for which the current pipeline will provide a starting point.

arXiv comment19 pages, 19 figures

References in corpus (55)

• Gaia Data Release 2. Summary of the contents and survey properties
• Weak Gravitational Lensing
• Observational Probes of Cosmic Acceleration
• KiDS-450: Cosmological parameter constraints from tomographic weak gravitational lensing
• The DEEP2 Galaxy Redshift Survey: Design, Observations, Data Reduction, and Redshifts
• The BAHAMAS project: Calibrated hydrodynamical simulations for large-scale structure cosmology
• Bayesian Galaxy Shape Measurement for Weak Lensing Surveys - III. Application to the Canada-France-Hawaii Telescope Lensing Survey
• Weak lensing for precision cosmology
• Cosmological parameters from lensing power spectrum and bispectrum tomography
• CFHTLenS: Improving the quality of photometric redshifts with precision photometry
• The Intrinsic Alignment of Galaxies and its Impact on Weak Gravitational Lensing in an Era of Precision Cosmology
• Practical Weak Lensing Shear Measurement with Metacalibration
• MegaPipe: the MegaCam image stacking pipeline at the Canadian Astronomical Data Centre
• Origins of weak lensing systematics, and requirements on future instrumentation (or knowledge of instrumentation)
• Cosmology with the shear-peak statistics
• Dark Energy Survey Year 3 Results: Weak Lensing Shape Catalogue
• Cosmology Constraints from the Weak Lensing Peak Counts and the Power Spectrum in CFHTLenS
• Cosmology constraints from shear peak statistics in Dark Energy Survey Science Verification data
• CFHTLenS: Mapping the Large Scale Structure with Gravitational Lensing
• A new approach to observational cosmology using the scattering transform
• KiDS-450: Cosmological Constraints from Weak Lensing Peak Statistics - II: Inference from Shear Peaks using N-body Simulations
• PSF calibration requirements for dark energy from cosmic shear
• MassiveNuS: Cosmological Massive Neutrino Simulations
• DES Y3 results: Blending shear and redshift biases in image simulations
• Probing Cosmology with Weak Lensing Minkowski Functionals
• Statistics of Dark Matter Halos from Gravitational Lensing
• KiDS-450: Cosmological Constraints from Weak Lensing Peak Statistics-I: Inference from Analytical Prediction of High Signal-to-Noise Ratio Convergence Peaks
• Cosmological Constraints From Weak Lensing Peak Statistics With CFHT Stripe 82 Survey
• Cosmological Information in Weak Lensing Peaks
• New Interpretable Statistics for Large Scale Structure Analysis and Generation
• Cosmological constraints from noisy convergence maps through deep learning
• A study of the sensitivity of shape measurements to the input parameters of weak lensing image simulations
• Cosmic Shear Cosmology Beyond 2-Point Statistics: A Combined Peak Count and Correlation Function Analysis of DES-Y1
• A new model to predict weak-lensing peak counts I. Comparison with $N$-body Simulations
• Dark Energy Survey Year 3 results: cosmology with moments of weak lensing mass maps -- validation on simulations
• Cosmological Forecast for non-Gaussian Statistics in large-scale weak Lensing Surveys
• Constraining Neutrino Mass with the Tomographic Weak Lensing Bispectrum
• Constraining neutrino mass with tomographic weak lensing peak counts
• Mocking the Weak Lensing universe: the LensTools python computing package
• Impact of Baryonic Processes on Weak Lensing Cosmology: Power Spectrum, Non-Local Statistics, and Parameter Bias
• Statistics of dark matter haloes expected from weak lensing surveys
• A Full $w$CDM Analysis of KiDS-1000 Weak Lensing Maps using Deep Learning
• The Origin of Weak Lensing Convergence Peaks
• Cosmological constraints with weak lensing peak counts and second-order statistics in a large-field survey
• The effects of the cluster environment on the galaxy mass-size relation in MACSJ J1206.2-0847
• Weak Lensing Minima and Peaks: Cosmological Constraints and the Impact of Baryons
• Going deep with Minkowski functionals of convergence maps
• Noise reduction for weak lensing mass mapping: An application of generative adversarial networks to Subaru Hyper Suprime-Cam first-year data
• Self-calibration of weak lensing systematic effects using combined two- and three-point statistics
• Hundreds of weak lensing shear-selected clusters from the Hyper Suprime-Cam Subaru Strategic Program S19A data
• Cosmology with photometric weak lensing surveys: constraints with redshift tomography of convergence peaks and moments
• ShapePipe: a new shape measurement pipeline and weak-lensing application to UNIONS/CFIS data
• Starlet l1-norm for weak lensing cosmology
• Propagating spatially-varying multiplicative shear bias to cosmological parameter estimation for stage-IV weak-lensing surveys
• Mapping Spatially Varying Additive Biases in Cosmic Shear Data

Cited by in corpus (11)

• Towards a full $w$CDM map-based analysis for weak lensing surveys
• Impact of baryonic feedback on HSC Y1 weak lensing non-Gaussian statistics
• Stage IV baryonic feedback correction for non-Gaussianity inference
• Starlet higher order statistics for galaxy clustering and weak lensing
• Accurate Kappa Reconstruction Algorithm for masked shear catalog (AKRA)
• AKRA 2.0: Accurate Kappa Reconstruction Algorithm for masked shear catalog
• Peaks in weak lensing mass maps for cluster astrophysics and cosmology
• Galaxies OBserved as Low-luminosity Identified Nebulae (GOBLIN): a catalog of 43,000 high-probability dwarf galaxy candidates in the UNIONS survey
• 6x2pt: Forecasting gains from joint weak lensing and galaxy clustering analyses with spectroscopic-photometric galaxy cross-correlations
• Impact of weak-lensing mass-mapping algorithms on cosmology inference
• Diagnosing Systematic Effects Using the Inferred Initial Power Spectrum