Disentangling magnification in combined shear-clustering analyses

Abstract

We investigate the sensitivity to the effects of lensing magnification on large-scale structure analyses combining photometric cosmic shear and galaxy clustering data (i.e. the now commonly called "3$\times$2-point" analysis). Using a Fisher matrix bias formalism, we disentangle the contribution to the bias on cosmological parameters caused by ignoring the effects of magnification in a theory fit from individual elements in the data vector, for Stage-III and Stage-IV surveys, assuming well-known redshift distributions, sample selection based on magnitude, and magnification strengths inferred from CFHTLenS and DES Y1 data. We show that the removal of elements of the data vectors that are dominated by magnification does not guarantee a reduction in the cosmological bias due to the magnification signal, but can instead increase the sensitivity to magnification. We find that the most sensitive elements of the data vector come from the shear-clustering cross-correlations, particularly between the highest-redshift shear bin and any lower-redshift lens sample, and that the parameters ${\Omega }_M$, $S_8={\sigma }_8\sqrt{{\Omega }_M/0.3}$ and $w_0$ show the most significant biases for both survey models. Our forecasts predict that current analyses are not significantly biased by magnification, but this bias will become highly significant with the continued increase of statistical power in the near future. We therefore conclude that future surveys should measure and model the magnification as part of their flagship "3$\times$2-point" analysis.

arXiv comment13 pages, 7 figures; matches MNRAS published version

References in corpus (35)

• Dark Energy Survey Year 1 Results: Cosmological Constraints from Galaxy Clustering and Weak Lensing
• The Dark Energy Camera
• Euclid Definition Study Report
• LSST Science Book, Version 2.0
• Dark Energy Survey Year 1 Results: Cosmological Constraints from Cosmic Shear
• The Cosmic Linear Anisotropy Solving System (CLASS) I: Overview
• The Dark Energy Survey Data Release 1
• Dark Energy Survey Year 1 Results: Constraints on Extended Cosmological Models from Galaxy Clustering and Weak Lensing
• KiDS-450 + 2dFLenS: Cosmological parameter constraints from weak gravitational lensing tomography and overlapping redshift-space galaxy clustering
• KiDS+GAMA: Cosmology constraints from a joint analysis of cosmic shear, galaxy-galaxy lensing and angular clustering
• The Dark Energy Survey Image Processing Pipeline
• Simultaneous measurement of cosmology and intrinsic alignments using joint cosmic shear and galaxy number density correlations
• Measuring the galaxy-mass and galaxy-dust correlations through magnification and reddening
• Systematic Bias in Cosmic Shear: Beyond the Fisher Matrix
• Dark Energy Survey Year 1 Results: Galaxy clustering for combined probes
• Cluster Mass Profiles from a Bayesian Analysis of Weak Lensing Distortion and Magnification Measurements: Applications to Subaru Data
• The CLASSgal code for Relativistic Cosmological Large Scale Structure
• Gravitational Lensing of Distant Field Galaxies by Rich Clusters: I. -- Faint Galaxy Redshift Distributions
• Second Order Corrections to Weak Lensing by Large-Scale Structure
• Weak lensing power spectra for precision cosmology: Multiple-deflection, reduced shear and lensing bias corrections
• Einstein's legacy in galaxy surveys
• A Detection of Weak Lensing Magnification using Galaxy Sizes and Magnitudes
• Euclid Preparation IV. Impact of undetected galaxies on weak-lensing shear measurements
• On the complementarity of galaxy clustering with cosmic shear and flux magnification
• Lensing Bias in Cosmic Shear
• Inferring the mass of sub-millimetre galaxies by exploiting their gravitational magnification of background galaxies
• The impact of relativistic effects on cosmological parameter estimation
• Size Bias in Galaxy Surveys
• Lensing convergence and the neutrino mass scale in galaxy redshift surveys
• The Impact of Magnification and Size Bias on Weak Lensing Power Spectrum and Peak Statistics
• Weak Lensing with Sizes, Magnitudes and Shapes
• Observational biases in flux magnification measurements
• Mitigating Systematic Errors in Angular Correlation Function Measurements from Wide Field Surveys
• Weak lensing magnification of SpARCS galaxy clusters
• Cluster mass profile reconstruction with size and flux magnification on the HST STAGES survey

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• Consistent lensing and clustering in a low-$S_8$ Universe with BOSS, DES Year 3, HSC Year 1 and KiDS-1000
• Euclid preparation: XIX. Impact of magnification on photometric galaxy clustering
• Dark Energy Survey Year 3 results: Magnification modeling and impact on cosmological constraints from galaxy clustering and galaxy-galaxy lensing
• Cosmological Constraint Precision of the Photometric and Spectroscopic Multi-probe Surveys of China Space Station Telescope (CSST)
• Magnification bias in galaxy surveys with complex sample selection functions
• The importance of magnification effects in galaxy-galaxy lensing
• Euclid: The reduced shear approximation and magnification bias for Stage IV cosmic shear experiments
• Developing a unified pipeline for large-scale structure data analysis with angular power spectra -- II. A case study for magnification bias and radio continuum surveys
• On cosmological bias due to the magnification of shear and position samples in modern weak lensing analyses
• Ultra-large-scale approximations and galaxy clustering: debiasing constraints on cosmological parameters
• Magnification Bias Estimators for Realistic Surveys: an Application to the BOSS Survey
• Constraining gravity with a new precision $E_G$ estimator using Planck + SDSS BOSS
• Post-Limber Weak Lensing Bispectrum, Reduced Shear Correction, and Magnification Bias Correction
• Almanac: MCMC-based signal extraction of power spectra and maps on the sphere
• Propagating spatially-varying multiplicative shear bias to cosmological parameter estimation for stage-IV weak-lensing surveys
• Impact of lensing magnification on the analysis of galaxy clustering in redshift space
• Intrinsic correlations of galaxy sizes in a hydrodynamical cosmological simulation
• Improving CMB constraints on early Universe physics with LSS: A multi-probe forecast including cross-covariance
• Forecasting the potential of weak lensing magnification to enhance LSST large-scale structure analyses