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Related papers: Intrinsic and extrinsic gravitational flexions

200 papers

We present an analytical formulation of gravitational lensing using familiar triaxial power-law mass distributions, where the 3-dimensional mass density is given by $\rho(X,Y,Z) = \rho_0 [1 + (\frac{X}{a})^2 + (\frac{Y}{b})^2 +…

Astrophysics · Physics 2009-10-30 Kyu-Hyun Chae , Valery K. Khersonsky , David A. Turnshek

We seek to understand the impact on shape estimators obtained from circular and elliptical shapelet models under two realistic conditions: (a) only a limited number of shapelet modes is available for the model, and (b) the intrinsic…

Instrumentation and Methods for Astrophysics · Physics 2014-07-24 P. Melchior , A. Boehnert , M. Lombardi , M. Bartelmann

Luminous tracers have been used extensively to map the large-scale matter distribution in the Universe. Similarly the dynamics of stars or galaxies can be used to estimate masses of galaxies and clusters of galaxies. However, assumptions…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-25 H. Hoekstra

We present fully nonparametric estimates of the frequency function of elliptical galaxy intrinsic shapes under the axisymmetric and triaxial hypotheses. If elliptical galaxies are assumed to be oblate or prolate, the frequency function of…

Astrophysics · Physics 2009-10-28 Benoit Tremblay , David Merritt

It is usually assumed that the ellipticity power spectrum measured in weak lensing observations can be expressed as an integral over the underlying matter power spectrum. This is true at second order in the gravitational potential. We…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Elisabeth Krause , Christopher M. Hirata

The theory of gravitational lensing is reviewed from a spacetime perspective, without quasi-Newtonian approximations. More precisely, the review covers all aspects of gravitational lensing where light propagation is described in terms of…

General Relativity and Quantum Cosmology · Physics 2010-10-19 Volker Perlick

The existence of galaxy intrinsic clustering severely hampers the weak lensing reconstruction from cosmic magnification. In paper I \citep{Yang2011}, we proposed a minimal variance estimator to overcome this problem. By utilizing the…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-21 Xinjuan Yang , Pengjie Zhang , Jun Zhang , Yu Yu

Using data from the HST Medium Deep Survey, a long-term Key Project, together with generically similar archived data, we have discovered evidence for weak gravitational `shear' of background field galaxies (I = 22 -- 26) in the vicinity of…

Astrophysics · Physics 2015-06-24 R. E. Griffiths , S. Casertano , M. Im , K. U. Ratnatunga

The capacity of Stage IV lensing surveys to measure the neutrino mass sum and differentiate between the normal and inverted mass hierarchies depends on the impact of nuisance parameters describing small-scale baryonic astrophysics and…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-09 David Copeland , Andy Taylor , Alex Hall

Weak gravitational lensing has proven to be a powerful tool to map directly the distribution of dark matter in the Universe. The technique, currently used, relies on the accurate measurement of the gravitational shear that corresponds to…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 S. Pires , A. Amara

In modeling strong gravitational lens systems, one often adopts simple models, such as singular isothermal elliptical density plus lowest-order external perturbation. However, such simple models may mislead us if the real mass distribution…

Astrophysics · Physics 2015-06-24 Yozo Kawano , Masamune Oguri , Takahiko Matsubara , Satoru Ikeuchi

Galaxies are known to be aligned toward specific directions within the large-scale structure. Such alignment signals become important for controlling the systematics of weak lensing surveys and for constraining galaxy formation and…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-24 Motonari Tonegawa , Teppei Okumura , Masao Hayashi

The GRavitational lEnsing Accuracy Testing 3 (GREAT3) challenge is the third in a series of image analysis challenges, with a goal of testing and facilitating the development of methods for analyzing astronomical images that will be used to…

Intrinsic alignments constitute the major astrophysical systematic for cosmological weak lensing surveys. We present a purely geometrical method with which one can study gravitational shear-intrinsic ellipticity correlations directly in…

Cosmology and Nongalactic Astrophysics · Physics 2010-08-23 B. Joachimi , P. Schneider

We investigate the practical implementation of Taylor's (2002) 3-dimensional gravitational potential reconstruction method using weak gravitational lensing, together with the requisite reconstruction of the lensing potential. This…

Astrophysics · Physics 2008-11-26 D. J. Bacon , A. N. Taylor

Correlations between intrinsic shear and the density field on large scales, a potentially important contaminant for cosmic shear surveys, have been robustly detected at low redshifts with bright galaxies in SDSS data. Here we present a more…

We describe the effects of weak gravitational lensing by cosmological large scale structure on the diffuse emission of 21 centimeter radiation from neutral hydrogen at high redshifts during the era of reionization. The ability to observe…

Astrophysics · Physics 2010-11-11 Kaisey S. Mandel , Matias Zaldarriaga

Weak-lensing shear estimates show a troublesome dependence on the apparent brightness of the galaxies used to measure the ellipticity: In several studies, the amplitude of the inferred shear falls sharply with decreasing source…

Instrumentation and Methods for Astrophysics · Physics 2012-11-26 Peter Melchior , Massimo Viola

The gravitational lensing, as well as the velocity field and the cosmological light-cone warp, changes the observed correlation function of high-redshift objects. We present an analytical expression of 3D correlation function,…

Astrophysics · Physics 2009-10-31 Takahiko Matsubara

We compute the two-point image correlation function for bright galaxies in the seventh data release of the Sloan Digital Sky Survey (SDSS) over angular scales 0.01' <= \theta <= 120' and projected separations 0.01 Mpc <= r <= 10 Mpc. We…

Cosmology and Nongalactic Astrophysics · Physics 2009-04-22 Tereasa G. Brainerd , Ingolfur Agustsson , Chad A. Madsen , Jeffrey A. Edmonds