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Related papers: Weak Lensing Mass Reconstruction: Flexion vs Shear

200 papers

I show how weak gravitational lensing can be used to image the 3-D mass distribution in the Universe. An inverse relation to the lensing equation, relating the lensing potential evaluated at each source to the full 3-D Newtonian potential,…

Astrophysics · Physics 2007-05-23 A. N. Taylor

In this review I will describe progress that has been made in determining masses of galaxy clusters using `weak lensing' and how this technique my be applied in the future to determine the dark matter distribution both on supercluster…

Astrophysics · Physics 2007-05-23 Nick Kaiser

We study the limits of accuracy for weak lensing maps of dark matter using diffuse 21-cm radiation from the pre-reionization epoch using simulations. We improve on previous "optimal" quadratic lensing estimators by using shear and…

Astrophysics · Physics 2009-11-13 Tingting Lu , Ue-Li Pen

Gravitational lensing directly measures mass density fluctuations along the lines of sight to very distant objects. No assumptions need to be made concerning bias, the ratio of fluctuations in galaxy density to mass density. Hence, lensing…

Astrophysics · Physics 2007-05-23 Joachim Wambsganss , Renyue Cen , Jeremiah P. Ostriker

We report a detection of the coherent distortion of faint galaxies arising from gravitational lensing by foreground structures. This ``cosmic shear'' is potentially the most direct measure of the mass power spectrum, as it is unaffected by…

Astrophysics · Physics 2011-05-05 David Bacon , Alexandre Refregier , Richard Ellis

We study how joint shear and magnification measurements improve the statistical precision of weak lensing mass calibration experiments, relative to standard shear-only analysis. For our magnification measurements, we consider not only the…

Cosmology and Nongalactic Astrophysics · Physics 2010-09-30 Eduardo Rozo , Fabian Schmidt

Gravitational lensing induces significant errors in the measured distances to high-redshift standard candles and standard sirens such as type-Ia supernovae, gamma-ray bursts, and merging supermassive black hole binaries. There will…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Stefan Hilbert , Jonathan R. Gair , Lindsay J. King

This paper details a description of the pattern of galaxy image distortion over the entire sky caused by the gravitational lensing which is the result of large scale inhomogeneities in our universe. We present a tensor spherical harmonic…

Astrophysics · Physics 2007-05-23 Albert Stebbins

The wealth of incoming and future cosmological observations will allow us to map out the structure and evolution of the observable universe to an unprecedented level of precision. Among these observations is the weak gravitational lensing…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 M. A. Troxel , Mustapha Ishak

We introduce a novel approach to reconstruct dark matter mass maps from weak gravitational lensing measurements. The cornerstone of the proposed method lies in a new modelling of the matter density field in the Universe as a mixture of two…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-26 J. -L. Starck , K. E. Themelis , N. Jeffrey , A. Peel , F. Lanusse

Weak lensing measurements are entering a precision era to statistically map the distribution of matter in the universe. The most common measurement has been of the variance of the projected surface density of matter, which corresponds to…

Astrophysics · Physics 2009-11-07 Tong-Jie Zhang , Ue-Li Pen , Pengjie Zhang , John Dubinski

Weak gravitational lensing surveys are rapidly becoming important tools to probe directly the mass density fluctuations in the universe and its background dynamics. Earlier studies have shown that it is possible to model the statistics of…

Astrophysics · Physics 2009-11-07 Patrick Valageas , Andrew J. Barber , Dipak Munshi

Cosmic shear probes the distribution of dark matter via gravitational lensing of distant, background galaxies. We describe our cosmic shear survey consisting of deep blank fields observed with the Keck II telescope. We have found biases in…

Astrophysics · Physics 2007-05-23 Richard Massey , David Bacon , Alexandre Refregier , Richard Ellis

A massive foreground cluster lens changes the shapes (shear effect) and number density (magnification effect) of the faint background galaxy population. In this paper we investigate how the shear, magnification and combined information can…

Astrophysics · Physics 2009-09-25 Peter Schneider , Lindsay King , Thomas Erben

Gravitational lensing can provide pure geometric tests of the structure of space-time, for instance by determining empirically the angular diameter distance-redshift relation. This geometric test has been demonstrated several times using…

The distinction between weak and strong lensing is somewhat arbitrary, and both regimes are manifestations of the same physical phenomenon: gravity bending the path of light. Nevertheless, these two regimes have to a large extent been…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-09 Ben David Normann , Kenny Solevåg-Hoti , Hans Georg Schaathun

We introduce a novel method for reconstructing the projected matter distributions of galaxy clusters with weak-lensing (WL) data based on convolutional neural network (CNN). Training datasets are generated with ray-tracing through…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-30 Sungwook E. Hong , Sangnam Park , M. James Jee , Dongsu Bak , Sangjun Cha

We present equations for the gravitational lensing flexion expected for an elliptical lens mass distribution. These can be reduced to one-dimensional finite integrals, thus saving significant computing time over a full two-dimensional…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 A. J. Hawken , S. L. Bridle

Weak lensing surveys exploit measurements of galaxy ellipticities. These measurements are subject to errors which degrade the cosmological information that can be extracted from the surveys. Here we propose a way of using the galaxy data…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-07 Alberto Vallinotto , Scott Dodelson , Pengjie Zhang

Recently, it has been shown that it is possible to reconstruct the projected mass distribution of a cluster from weak lensing provided that both the geometry of the universe and the probability distribution of galaxy redshifts are known;…

Astrophysics · Physics 2007-05-23 Marco Lombardi , Giuseppe Bertin
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