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Related papers: Approaching the Cramer-Rao Bound in Weak Lensing w…

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Weak lensing can be observed through a number of effects on the images of distant galaxies; their shapes are sheared, their sizes and fluxes (magnitudes) are magnified and their positions on the sky are modified by the lensing field. Galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-12 Justin Alsing , Donnacha Kirk , Alan Heavens , Andrew Jaffe

The present generation of weak lensing surveys will be superseded by surveys run from space with much better sky coverage and high level of signal to noise ratio, such as SNAP. However, removal of any systematics or noise will remain a…

Astrophysics · Physics 2009-11-10 Dipak Munshi , Patrick Valageas

The one-point probability distribution function (PDF) is a powerful summary statistic for non-Gaussian cosmological fields, such as the weak lensing (WL) convergence reconstructed from galaxy shapes or cosmic microwave background (CMB)…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-04 Leander Thiele , J. Colin Hill , Kendrick M. Smith

The weak distortions produced by gravitational lensing in the images of background galaxies provide a method to measure directly the distribution of mass in the universe. However this technique requires high precision measurements of the…

Astrophysics · Physics 2009-10-31 Jason Rhodes , Alexandre Refregier , Ed Groth

The unprecedented amount and the excellent quality of lensing data that the upcoming ground- and space-based surveys will produce represent a great opportunity to shed light on the questions that still remain unanswered concerning our…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-27 Carolina Parroni , Edouard Tollet , Vincenzo F. Cardone , Roberto Maoli , Roberto Scaramella

We have developed a new technique for weak lensing analysis, with which the effect of the point spread function (PSF) on small galaxy images can be corrected for accurately. Rather than relying on weighted second moments of detected images,…

Astrophysics · Physics 2016-08-30 Konrad Kuijken

Now that weak lensing signals on the order of a percent are actively being searched for (cosmic shear, galaxy-galaxy lensing, large radii in clusters...) it is important to investigate how accurately weak shears can be determined. Many…

Astrophysics · Physics 2016-08-30 K. Kuijken

We perform a measurement of the mass--richness relation of the redMaPPer galaxy cluster catalogue using weak lensing data from the Sloan Digital Sky Survey. We have carefully characterized a broad range of systematic uncertainties,…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-05 Melanie Simet , Tom McClintock , Rachel Mandelbaum , Eduardo Rozo , Eli Rykoff , Erin Sheldon , Risa H. Wechsler

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…

Instrumentation and Methods for Astrophysics · Physics 2021-03-03 Arun Kannawadi , Erik Rosenberg , Henk Hoekstra

We study the covariance properties of real space correlation function estimators -- primarily galaxy-shear correlations, or galaxy-galaxy lensing -- using SDSS data for both shear catalogs and lenses (specifically the BOSS LOWZ sample).…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-30 Sukhdeep Singh , Rachel Mandelbaum , Uroš Seljak , Anže Slosar , Jose Vazquez Gonzalez

The Shear TEsting Programme, STEP, is a collaborative project to improve the accuracy and reliability of all weak lensing measurements in preparation for the next generation of wide-field surveys. In this first STEP paper we present the…

Upcoming surveys such as \LSST{} and \Euclid{} will significantly improve the power of weak lensing as a cosmological probe. To maximise the information that can be extracted from these surveys, it is important to explore novel statistics…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-18 Christopher T. Davies , Marius Cautun , Benjamin Giblin , Baojiu Li , Joachim Harnois-Déraps , Yan-Chuan Cai

Large catalogs of shear-selected peaks have recently become a reality. In order to properly interpret the abundance and properties of these peaks, it is necessary to take into account the effects of the clustering of source galaxies, among…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Fabian Schmidt , Eduardo Rozo

The first half of this paper explores the origin of systematic biases in the measurement of weak gravitational lensing. Compared to previous work, we expand the investigation of PSF instability and fold in for the first time the effects of…

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

Cosmic shear is a primary cosmological probe for several present and upcoming surveys investigating dark matter and dark energy, such as Euclid or WFIRST. The probe requires an extremely accurate measurement of the shapes of millions of…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-04 Malte Tewes , Thibault Kuntzer , Reiko Nakajima , Frédéric Courbin , Hendrik Hildebrandt , Tim Schrabback

This paper extends the method introduced in Rivi et al. (2016b) to measure galaxy ellipticities in the visibility domain for radio weak lensing surveys. In that paper we focused on the development and testing of the method for the simple…

Instrumentation and Methods for Astrophysics · Physics 2018-04-16 Marzia Rivi , Lance Miller

Weak lensing by large-scale structure is a powerful technique to probe the dark components of the universe. To understand the measurement process of weak lensing and the associated systematic effects, image simulations are becoming…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-27 Claudio Bruderer , Chihway Chang , Alexandre Refregier , Adam Amara , Joel Berge , Lukas Gamper

Weak lensing has become an increasingly important tool in cosmology and the use of galaxy shapes to measure cosmic shear has become routine. The weak-lensing distortion tensor contains two other effects in addition to the two components of…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-19 Daniel B. Thomas , Lee Whittaker , Stefano Camera , Michael L. Brown

Exploiting the full statistical power of future cosmic shear surveys will necessitate improvements to the accuracy with which the gravitational lensing signal is measured. We present a framework for calibrating shear with image simulations…