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Related papers: A new cosmic shear function: Optimised E-/B-mode d…

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We show that the lensing efficiency of cosmic shear generically has a simple shape, even in the case of a tomographic survey with badly behaved photometric redshifts. We argue that source distributions for cosmic shear can therefore be more…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-21 Nicolas Tessore , Ian Harrison

Cosmological random fields are often analysed in spherical Fourier-Bessel basis. Compared to the Cartesian Fourier basis this has an advantage of properly taking into account some of the relevant physical processes (redshift-space…

Cosmology and Nongalactic Astrophysics · Physics 2019-06-17 Lado Samushia

We explore the weak lensing E- and B-mode shear signals of a field of galaxy clusters using both large scale structure N-body simulations and multi-color Suprime-cam & Hubble Space Telescope observations. Using the ray-traced and observed…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-17 Andrew K. Bradshaw , M. James Jee , J. Anthony Tyson

Cosmic shear measurements have now improved to the point where they deserve to be treated on par with CMB and galaxy clustering data for cosmological parameter analysis, using the full measured aperture mass variance curve rather than a…

Astrophysics · Physics 2009-10-07 Xiaomin Wang , Max Tegmark , Bhuvnesh Jain , Matias Zaldarriaga

We present the optimal convergence and shear estimators for lensing reconstruction from the cosmic microwave background temperature field. This generalizes the deflection estimator, is sensitive to non-lensing modes, provides internal…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-18 Hong-Ming Zhu , Ue-Li Pen

We present the results of weak gravitational lensing statistics in four different cosmological $N$-body simulations. The data has been generated using an algorithm for the three-dimensional shear, which makes use of a variable softening…

Astrophysics · Physics 2009-10-31 Andrew J. Barber , Peter A. Thomas , H. M. P. Couchman , C. J. Fluke

Statistical weak lensing by large-scale structure -- cosmic shear -- is a promising cosmological tool, which has motivated the design of several large upcoming surveys. Here, we present a measurement of cosmic shear using coadded Sloan…

Cosmology and Nongalactic Astrophysics · Physics 2011-12-15 Eric M. Huff , Tim Eifler , Christopher M. Hirata , Rachel Mandelbaum , David Schlegel , Uros Seljak

We present a combined cosmic shear analysis of the modeling of line-of-sight distortions on strongly lensed extended arcs and galaxy shape measurements in the COSMOS field. We develop a framework to predict the covariance of strong lensing…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-14 Felix Arjun Kuhn , Claudio Bruderer , Simon Birrer , Adam Amara , Alexandre Réfrégier

The current methods available to estimate gravitational shear from astronomical images of galaxies introduce systematic errors which can affect the accuracy of weak lensing cosmological constraints. We study the impact of KSB shape…

The ratio of the average tangential shear signal of different weak lensing source populations around the same lens galaxies, also known as a shear ratio, provides an important test of lensing systematics and a potential source of…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-01 Ni Emas , Chris Blake , Rossana Ruggeri , Anna Porredon

We have analysed 53 square degrees of imaging data from the Red-Sequence Cluster Survey (RCS), and measured the excess correlations in the shapes of galaxies on scales out to ~1.5 degrees. We separate the signal into an ``E''- (lensing) and…

Astrophysics · Physics 2009-11-07 Henk Hoekstra , Howard Yee , Mike Gladders

We compute the angular power spectrum of the $B$-modes of the weak-lensing shear in a spatially anisotropic spacetime. We find that there must also exist off-diagonal correlations between the $E$-modes, $B$-modes, and convergence that allow…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-13 Thiago S. Pereira , Cyril Pitrou , Jean-Philippe Uzan

Weak-lensing searches for galaxy clusters are plagued by low completeness and purity, severely limiting their usefulness for constraining cosmological parameters with the cluster mass function. A significant fraction of `false positives'…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 J. P. Dietrich , J. Hartlap

We study the statistics of peaks in a weak lensing reconstructed mass map of the first 450 square degrees of the Kilo Degree Survey. The map is computed with aperture masses directly applied to the shear field with an NFW-like compensated…

During the past few years, secure detections of cosmic shear have been obtained, manifest in the correlation of the observed ellipticities of galaxies. Constraints have already been placed on cosmological parameters, such as the…

Astrophysics · Physics 2009-11-07 Lindsay King , Peter Schneider

Precision cosmology benefits from extracting maximal information from cosmic structures, motivating the use of higher-order statistics (HOS) at small spatial scales. However, predicting how baryonic processes modify matter statistics at…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-07 Alan Junzhe Zhou , Marco Gatti , Dhayaa Anbajagane , Scott Dodelson , Matthieu Schaller , Joop Schaye

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…

Previous work on three-point statistics of cosmic shear has mainly concentrated on the convergence, or on aperture measures of the shear. However, as has become clear recently for the two-point statistics of cosmic shear, the basic quantity…

Astrophysics · Physics 2009-11-07 Peter Schneider , Marco Lombardi

We present a new method to extract cosmological constraints from weak lensing (WL) peak counts, which we denote as `the hierarchical algorithm'. The idea of this method is to combine information from WL maps sequentially smoothed with a…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Laura Marian , Robert E. Smith , Stefan Hilbert , Peter Schneider