Generalized shear-ratio tests: A new relation between cosmological distances, and a diagnostic for a redshift-dependent multiplicative bias in shear measurements

Abstract

We derive a new relation between cosological distances, valid in any (statistically) isotropic space-time and independent of cosmological parameters or even the validity of the field equation of General Relativity. In particular, this relation yields an equation between those distance ratios which are the geometrical factors determining the strength of the gravitational lensing effect of mass concentrations. Considering a combination of weak lensing shear ratios, based on lenses at two different redshifts, and sources at three different redshifts, we derive a relation between shear-ratio tests which must be identically satisfied. A redshift-dependent multiplicative bias in shear estimates will violate this relation, and thus can be probed by this generalized shear-ratio test. Combining the lensing effect for lenses at three different redshifts and three different source redshifts, a relation between shear ratios is derived which must be valid independent of a multiplicative bias. We propose these generalized shear-ratio tests as a diagnostic for the presence of systematics in upcoming weak lensing surveys.

4 pages

References in corpus (4)

• The Shear TEsting Programme 2: Factors affecting high precision weak lensing analyses
• Means of confusion: how pixel noise affects shear estimates for weak gravitational lensing
• Probing dark energy with the shear-ratio geometric test
• Hierarchical probabilistic inference of cosmic shear

Cited by in corpus (16)

• KiDS-450: Cosmological parameter constraints from tomographic weak gravitational lensing
• Dark Energy Survey Year 3 Results: Cosmology from Cosmic Shear and Robustness to Data Calibration
• KiDS+VIKING-450: Cosmic shear tomography with optical+infrared data
• KiDS-1000 catalogue: Redshift distributions and their calibration
• Dark Energy Survey Year 3 Results: Exploiting small-scale information with lensing shear ratios
• KiDS-i-800: Comparing weak gravitational lensing measurements in same-sky surveys
• KiDS-SBI: Simulation-based inference analysis of KiDS-1000 cosmic shear
• Doubling Strong Lensing as a Cosmological Probe
• The FLAMINGO project: Baryonic impact on weak gravitational lensing convergence peak counts
• Double Source Lensing Probing High Redshift Cosmology
• KiDS+VIKING-450: An internal-consistency test for cosmic shear tomography with a colour-based split of source galaxies
• Systematic tests for position-dependent additive shear bias
• Magnification bias in the shear-ratio test: a viable mitigation strategy
• Hyper Suprime-Cam Y3 results: photo-$z$ bias calibration with lensing shear ratios and cosmological constraints from cosmic shear
• Reconstructing spatially-varying multiplicative bias for Stage IV weak lensing galaxy surveys with a quadratic estimator
• Ray-traced weak lensing convergence in screened modified gravity theories