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Related papers: Shear-flexion cross-talk in weak-lensing measureme…

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We study the ability of weak lensing surveys to detect galaxy clusters and constrain cosmological parameters, in particular the equation of state of dark energy. There are two major sources of noise for weak lensing cluster measurements:…

Astrophysics · Physics 2009-11-11 Laura Marian , Gary M. Bernstein

Galaxies are biased tracers of the matter density on cosmological scales. For future tests of galaxy models, we refine and assess a method to measure galaxy biasing as function of physical scale $k$ with weak gravitational lensing. This…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-24 Patrick Simon , Stefan Hilbert

We combine photometry and lens modeling to study the properties of 17 gravitational lens galaxies between z=0.1 and 1. Most of the lens galaxies are passively evolving early-type galaxies, with a few spirals. The colors, scale lengths, and…

Astrophysics · Physics 2010-03-01 C. R. Keeton , C. S. Kochanek , E. E. Falco

The gravitational lensing equations for convergence, potential, shear, and flexion are simple in polar coordinates and separate under a multipole expansion once the shear and flexion spinors are rotated into a ``tangential'' basis. We use…

Astrophysics · Physics 2011-02-11 Gary M. Bernstein , Reiko Nakajima

We measure the weak lensing shear around galaxy troughs, i.e. the radial alignment of background galaxies relative to underdensities in projections of the foreground galaxy field over a wide range of redshift in Science Verification data…

Context. Weak gravitational lensing is a powerful probe of large-scale structure and cosmology. Most commonly, second-order correlations of observed galaxy ellipticities are expressed as a projection of the matter power spectrum,…

Cosmology and Nongalactic Astrophysics · Physics 2010-08-25 Martin Kilbinger

We show with analytic models that the assumption of uncorrelated intrinsic ellipticities of target sources that is usually made in searches for weak gravitational lensing due to large-scale mass inhomogeneities (``field lensing'') is…

Astrophysics · Physics 2009-12-15 Paolo Catelan , Marc Kamionkowski , Roger D. Blandford

In these lectures I give an overview of gravitational lensing, concentrating on theoretical aspects, including derivations of some of the important results. Topics covered include the determination of surface mass densities of intervening…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-08 Alan Heavens

We have previously reported the discovery of strong gravitational lensing by faint elliptical galaxies using the WFPC2 on HST and here we investigate their potential usefulness in putting constraints on lens mass models. We compare various…

Astrophysics · Physics 2009-11-06 Adam Knudson , Kavan U. Ratnatunga , Richard E. Griffith

It has recently been argued that the observed ellipticities of galaxies may be determined at least in part by the primordial tidal gravitational field in which the galaxy formed. Long-range correlations in the tidal field could thus lead to…

Astrophysics · Physics 2017-08-23 Jonathan Mackey

Weak gravitational lensing can cause displacements, magnification, rotation and shearing of the images of distant galaxies. Most studies focus on the shear and magnification effects since they are more easily observed. In this paper we…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-04 Chihway Chang , Bhuvnesh Jain

We present a new shear estimator for weak lensing observations which properly accounts for the effects of a realistic point spread function (PSF). Images of faint galaxies are subject to gravitational shearing followed by smearing with the…

Astrophysics · Physics 2009-10-31 Nick Kaiser

The propagation of gravitational waves can be described in terms of null geodesics by using the geometrical optics approximation. However, at large but finite frequencies the propagation is affected by the spin-orbit coupling corrections to…

General Relativity and Quantum Cosmology · Physics 2024-10-29 Marius A. Oancea , Richard Stiskalek , Miguel Zumalacárregui

One of the most powerful techniques to study the dark sector of the Universe is weak gravitational lensing. In practice, to infer the reduced shear, weak lensing measures galaxy shapes, which are the consequence of both the intrinsic…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-07 Sami-Matias Niemi , Thomas Kitching , Mark Cropper

Weak gravitational lensing has become a powerful probe of large-scale structure and cosmological parameters. Precision weak lensing measurements require an understanding of the intrinsic alignment of galaxy ellipticities, which can in turn…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Jonathan Blazek , Matthew McQuinn , Uros Seljak

It is well known gravitational lensing, mainly via magnification bias, modifies the observed galaxy/quasar clustering. Such discussions have largely focused on the 2D angular correlation. Here and in a companion paper (Paper II) we explore…

Astrophysics · Physics 2008-11-26 Lam Hui , Enrique Gaztanaga , Marilena LoVerde

Galaxy-galaxy-galaxy lensing (G3L) is a powerful tool for constraining the three-point correlation between the galaxy and matter distribution and thereby models of galaxy evolution. We propose three improvements to current measurements of…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-29 Laila Linke , Patrick Simon , Peter Schneider , Stefan Hilbert

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

Cosmic shear is the distortion of images of distant galaxies due to weak gravitational lensing by the large-scale structure in the Universe. Such images are coherently deformed by the tidal field of matter inhomogeneities along the line of…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-22 Martin Kilbinger

We introduce a novel approach for detecting gravitational waves through their influence on the shape of resolved astronomical objects. This method, complementary to pulsar timing arrays and astrometric techniques, explores the…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-22 Giorgio Mentasti , Carlo R. Contaldi