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Related papers: Noise bias in weak lensing shape measurements

200 papers

In the theory of structure formation, galaxies are biased tracers of the underlying matter density field. The statistical relation between galaxy and matter density field is commonly referred as galaxy bias. In this paper, we test the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Eric Jullo , Jason Rhodes , Alina Kiessling , James E. Taylor , Richard Massey , Joel Berge , Carlo Schimd , Jean-Paul Kneib , Nick Scoville

Tests of general relativity (GR) can be systematically biased when our waveform models are inaccurate. We here study systematic biases in tests of general relativity induced by neglecting lensing effects for millilensed gravitational-wave…

General Relativity and Quantum Cosmology · Physics 2024-10-30 Anna Liu , Rohit S. Chandramouli , Otto A. Hannuksela , Nicolás Yunes , Tjonnie G. F. Li

Weak lensing is emerging as a powerful observational tool to constrain cosmological models, but is at present limited by an incomplete understanding of many sources of systematic error. Many of these errors are multiplicative and depend on…

We derive an estimator of weak gravitational lensing shear from background galaxy images that avoids noise-induced biases through a rigorous Bayesian treatment of the measurement. The derived shear estimator disposes with the assignment of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Gary M. Bernstein , Robert Armstrong

For cosmic shear to become an accurate cosmological probe, systematic errors in the shear measurement method must be unambiguously identified and corrected for. Previous work of this series has demonstrated that cosmic shears can be…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Jun Zhang , Wentao Luo , Sebastien Foucaud

A likelihood-based method for measuring weak gravitational lensing shear in deep galaxy surveys is described and applied to the Canada-France-Hawaii Telescope (CFHT) Lensing Survey (CFHTLenS). CFHTLenS comprises 154 sq deg of multicolour…

The VST Optical Imaging of the CDFS and ES1 Fields (VOICE) Survey is proposed to obtain deep optical $ugri$ imaging of the CDFS and ES1 fields using the VLT Survey Telescope (VST). At present, the observations for the CDFS field have been…

Weak gravitational lensing provides a unique method to directly measure the distribution of mass in the universe. Because the distortions induced by lensing in the shape of background galaxies are small, the measurement of weak lensing…

Astrophysics · Physics 2009-11-06 Alexandre Refregier , David Bacon

In order to reach the required performance of Stage-III and IV weak lensing surveys, cosmic shear measurements have to rely on external simulations to calibrate residual biases. Over the years, several techniques have been developed to…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-11 G. Congedo , A. N. Taylor

We extend the Bayesian model fitting shape measurement method presented in Miller et al. (2007) and use the method to estimate the shear from the Shear TEsting Programme simulations (STEP). The method uses a fast model fitting algorithm…

Astrophysics · Physics 2009-11-13 T. D. Kitching , L. Miller , C. E. Heymans , L. van Waerbeke , A. F. Heavens

Weak lensing surveys have become a powerful tool for mapping mass distributions and constraining the expansion history of our Universe, but continuum surveys must average over a large number of galaxies to average down the ellipticity noise…

Astrophysics · Physics 2009-11-11 Miguel F. Morales

Current optical imaging surveys for cosmology are covering large areas of sky. To exploit the statistical power of these surveys for weak lensing measurements requires shape measurement methods with subpercent systematic errors. We…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-08 Ricardo Herbonnet , Axel Buddendiek , Konrad Kuijken

We describe and test the pipeline used to measure the weak lensing shear signal from the Kilo Degree Survey (KiDS). It includes a novel method of `self-calibration' that partially corrects for the effect of noise bias. We also discuss the…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-12 Ian Fenech Conti , Ricardo Herbonnet , Henk Hoekstra , Julian Merten , Lance Miller , Massimo Viola

The use of large, X-ray selected galaxy cluster catalogues for cosmological analyses requires a thorough understanding of the X-ray mass estimates. Weak gravitational lensing is an ideal method to shed light on such issues, due to its…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-05 Melanie Simet , Nicholas Battaglia , Rachel Mandelbaum , Uroš Seljak

The Nancy Grace Roman Space Telescope, set to launch in 2026, will bring unprecedented precision to measurements of weak gravitational lensing. Because weak lensing is an inherently small signal, it is imperative to minimize systematic…

Instrumentation and Methods for Astrophysics · Physics 2025-12-09 Katherine Laliotis , Emily Macbeth , Christopher M. Hirata , Kaili Cao , Masaya Yamamoto , Michael Troxel

Weak lensing by large-scale structure allows a direct measure of the dark matter distribution. We have used parallel images taken with the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope to measure weak lensing, or…

Parametric modeling of galaxy cluster density profiles from weak lensing observations leads to a mass bias, whose detailed understanding is critical in deriving accurate mass-observable relations for constraining cosmological models.…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-17 Martin W. Sommer , Tim Schrabback , Douglas E. Applegate , Stefan Hilbert , Behzad Ansarinejad , Benjamin Floyd , Sebastian Grandis

The weak gravitational lensing effect, small coherent distortions of galaxy images by means of a gravitational tidal field, can be used to study the relation between the matter and galaxy distribution. In this context, weak lensing has so…

Astrophysics · Physics 2014-11-18 P. Simon , P. Watts , P. Schneider , H. Hoekstra , M. D. Gladders , H. K. C. Yee , B. C. Hsieh , H. Lin

Kinematic weak lensing describes the distortion of a galaxy's projected velocity field due to lensing shear, an effect recently reported for the first time by Gurri et al. based on a sample of 18 galaxies at $z \sim 0.1$. In this paper, we…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-08 Brian DiGiorgio , Kevin Bundy , Kyle B. Westfall , Alexie Leauthaud , David Stark

We study various measures of weak lensing distortions in future surveys, taking into account the noise arising from the finite survey size and the intrinsic ellipticity of galaxies. We also consider a realistic redshift distribution of the…

Astrophysics · Physics 2009-11-10 Patrick Valageas , Dipak Munshi , Andrew J. Barber