Mitigating the effects of undersampling in weak lensing shear estimation with metacalibration

Abstract

Metacalibration is a state-of-the-art technique for measuring weak gravitational lensing shear from well-sampled galaxy images. We investigate the accuracy of shear measured with metacalibration from fitting elliptical Gaussians to undersampled galaxy images. In this case, metacalibration introduces aliasing effects leading to an ensemble multiplicative shear bias about 0.01 for Euclid, and even larger for the Roman Space Telescope, well exceeding the missions' requirements. We find that this aliasing bias can be mitigated by computing shapes from weighted moments with wider Gaussians as weight functions, thereby trading bias for a slight increase in variance of the measurements. We show that this approach is robust to the point-spread function in consideration and meets the stringent requirements of Euclid for galaxies with moderate to high signal-to-noise ratios. We therefore advocate metacalibration as a viable shear measurement option for weak lensing from upcoming space missions.

arXiv comment17 pages, 12 figures, 3 tables; matches the published version in MNRAS

References in corpus (76)

• LSST: from Science Drivers to Reference Design and Anticipated Data Products
• Weak Gravitational Lensing
• The Cosmic Evolution Survey (COSMOS) -- Overview
• The Hyper Suprime-Cam SSP Survey: Overview and Survey Design
• Wide-Field InfrarRed Survey Telescope-Astrophysics Focused Telescope Assets WFIRST-AFTA 2015 Report
• Euclid Definition Study Report
• LSST Science Book, Version 2.0
• Drizzle: A Method for the Linear Reconstruction of Undersampled Images
• A Method for Weak Lensing Observations
• KiDS-1000 Cosmology: Cosmic shear constraints and comparison between two point statistics
• The COSMOS Survey: Hubble Space Telescope / Advanced Camera for Surveys (HST/ACS) Observations and Data Processing
• Dark Energy Survey Year 1 Results: Cosmological Constraints from Cosmic Shear
• Cosmology from cosmic shear power spectra with Subaru Hyper Suprime-Cam first-year data
• Cosmology with cosmic shear observations: a review
• Shapes and Shears, Stars and Smears: Optimal Measurements for Weak Lensing
• The Shear TEsting Programme 1: Weak lensing analysis of simulated ground-based observations
• The Hyper Suprime-Cam Software Pipeline
• Bayesian Galaxy Shape Measurement for Weak Lensing Surveys - III. Application to the Canada-France-Hawaii Telescope Lensing Survey
• Weak Gravitational Lensing with COSMOS: Galaxy Selection and Shape Measurements
• Weak Gravitational Lensing and its Cosmological Applications
• The Kilo-Degree Survey
• The Canadian Cluster Comparison Project: detailed study of systematics and updated weak lensing masses
• Shear calibration biases in weak lensing surveys
• Weak lensing for precision cosmology
• KiDS+VIKING-450: Cosmic shear tomography with optical+infrared data
• Detection of weak lensing by a cluster of galaxies at z=0.83
• Practical Weak Lensing Shear Measurement with Metacalibration
• Bayesian Galaxy Shape Measurement for Weak Lensing Surveys -I. Methodology and a Fast Fitting Algorithm
• Dark Energy Survey Year 1 Results: Weak Lensing Shape Catalogues
• The Wide Field Infrared Survey Telescope: 100 Hubbles for the 2020s
• A New Shear Estimator for Weak Lensing Observations
• GREAT3 results I: systematic errors in shear estimation and the impact of real galaxy morphology
• Weak lensing shear calibration with simulations of the HSC survey
• The Third Gravitational Lensing Accuracy Testing (GREAT3) Challenge Handbook
• The brighter-fatter effect and pixel correlations in CCD sensors
• Calibration of weak-lensing shear in the Kilo-Degree Survey
• Astrophysically Motivated Bulge-Disk Decompositions of SDSS Galaxies
• Means of confusion: how pixel noise affects shear estimates for weak gravitational lensing
• Metacalibration: Direct Self-Calibration of Biases in Shear Measurement
• Handbook for the GREAT08 Challenge: An image analysis competition for cosmological lensing
• Combining Undersampled Dithered Images
• IM3SHAPE: A maximum-likelihood galaxy shear measurement code for cosmic gravitational lensing
• Shape measurement biases from underfitting and ellipticity gradients
• Measurement and Calibration of Noise Bias in Weak Lensing Galaxy Shape Estimation
• Towards emulating cosmic shear data: Revisiting the calibration of the shear measurements for the Kilo-Degree Survey
• Precision simulation of ground-based lensing data using observations from space
• A study of the sensitivity of shape measurements to the input parameters of weak lensing image simulations
• Euclid Preparation IV. Impact of undetected galaxies on weak-lensing shear measurements
• Weak gravitational shear and flexion with polar shapelets
• Mitigating Shear-dependent Object Detection Biases with Metacalibration
• Dark Energy Survey Year 1 Results: The Impact of Galaxy Neighbours on Weak Lensing Cosmology with im3shape
• Gravitational Lensing Accuracy Testing 2010 (GREAT10) Challenge Handbook
• The Ellipticity Distribution of Ambiguously Blended Objects
• The effects of charge transfer inefficiency (CTI) on galaxy shape measurements
• On the shear estimation bias induced by the spatial variation of colour across galaxy profiles
• Optimal Linear Image Combination
• Limitations of model fitting methods for lensing shear estimation
• The impact of galaxy colour gradients on cosmic shear measurement
• Measuring the Cosmic Shear in Fourier Space
• WFIRST Science Investigation Team "Cosmology with the High Latitude Survey" Annual Report 2017
• Impact of Atmospheric Chromatic Effects on Weak Lensing Measurements
• A Synthetic Roman Space Telescope High-Latitude Imaging Survey: Simulation Suite and the Impact of Wavefront Errors on Weak Gravitational Lensing
• Exploring the brighter fatter effect with the Hyper Suprime-Cam
• How well can Charge Transfer Inefficiency be corrected? A parameter sensitivity study for iterative correction
• A highly precise shear bias estimator independent of the measured shape noise
• Wavelength Dependent PSFs and their impact on Weak Lensing Measurements
• The Impact of Interpixel Capacitance in CMOS Detectors on PSF shapes and Implications for WFIRST
• Calibration of colour gradient bias in shear measurement using HST/CANDELS data
• The LSST DESC Data Challenge 1: Generation and Analysis of Synthetic Images for Next Generation Surveys
• Accounting for object detection bias in weak gravitational lensing studies
• The effect of detector nonlinearity on WFIRST PSF profiles for weak gravitational lensing measurements
• The impact of cosmic variance on simulating weak lensing surveys
• Weak-lensing shear estimates with general adaptive moments, and studies of bias by pixellation, PSF distortions, and noise
• Noise from Undetected Sources in Dark Energy Survey Images
• Weak Gravitational Lensing Systematics from Image Combination
• The impact of correlated noise on galaxy shape estimation for weak lensing

Cited by in corpus (12)

• Euclid. I. Overview of the Euclid mission
• Cosmology Intertwined: A Review of the Particle Physics, Astrophysics, and Cosmology Associated with the Cosmological Tensions and Anomalies
• Point spread function modelling for astronomical telescopes: a review focused on weak gravitational lensing studies
• Accounting for object detection bias in weak gravitational lensing studies
• Weak Gravitational Lensing Shear Estimation with Metacalibration for the Roman High-Latitude Imaging Survey
• The First Weak-lensing Analysis with the James Webb Space Telescope: SMACS J0723.3-7327
• Simulating image coaddition with the Nancy Grace Roman Space Telescope: I. Simulation methodology and general results
• A fully data-driven algorithm for accurate shear estimation
• A Differentiable Perturbation-based Weak Lensing Shear Estimator
• Simulating image coaddition with the Nancy Grace Roman Space Telescope: II. Analysis of the simulated images and implications for weak lensing
• Analysis of biasing from noise from the Nancy Grace Roman Space Telescope: implications for weak lensing
• Cosmology with the Roman Space Telescope -- Synergies with CMB lensing