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Related papers: Weak-lensing $B$-modes as a probe of the isotropy …

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This article details the computation of the two-point correlators of the convergence, $E$- and $B$-modes of the cosmic shear induced by the weak-lensing by large scale structure assuming that the background spacetime is spatially…

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

The Cosmological Principle is a cornerstone of the standard model of cosmology and shapes how we view the Universe and our place within it. It is imperative, then, to devise multiple observational tests which can identify and quantify…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-13 James Adam , Roy Maartens , Julien Larena , Chris Clarkson

This article derives a multipolar hierarchy for the propagation of the weak-lensing shear and convergence in a general spacetime. The origin of B-modes, in particular on large angular scales, is related to the local isotropy of space. Known…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-20 Cyril Pitrou , Jean-Philippe Uzan , Thiago S. Pereira

We present a field-based signal extraction of weak lensing from noisy observations on the curved and masked sky. We test the analysis on a simulated Euclid-like survey, using a Euclid-like mask and noise level. To make optimal use of the…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-09 A. Loureiro , L. Whiteway , E. Sellentin , J. S. Lafaurie , A. H. Jaffe , A. F. Heavens

We present a comprehensive full-sky 3-dimensional analysis of the weak-lensing fields and their corresponding power spectra. Using the formalism of spin-weight spherical harmonics and spherical Bessel functions, we relate the two-point…

Astrophysics · Physics 2009-11-10 P. G. Castro , A. F. Heavens , T. D. Kitching

We propose to use a simple observable, the fractional area of "hot spots" in weak lensing mass maps which are detected with high significance, to determine background cosmological parameters. Because these high-shear regions are directly…

Astrophysics · Physics 2008-09-24 Sheng Wang , Zoltan Haiman , Morgan May , John Kehayias

The standard cosmological model assumes the Cosmological Principle. However, recent observations hint at possible violations of isotropy on large scales, possibly through late-time anisotropic expansion. Here we investigate the potential of…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-12 James Adam , Roy Maartens , Julien Larena , Chris Clarkson , Ruth Durrer

We develop a method for estimating the shear power spectra from weak lensing observations and test it on simulated data. Our method describes the shear field in terms of angular power spectra and cross correlation of the two shear modes…

Astrophysics · Physics 2008-11-26 Wayne Hu , Martin White

Cosmological defects result from cosmological phase transitions in the early Universe and the dynamics reflects their symmetry-breaking mechanisms. These cosmological defects may be probed through weak lensing effects because they interact…

Cosmology and Nongalactic Astrophysics · Physics 2017-06-28 Shohei Saga , Kouichirou Horiguchi , Kiyotomo Ichiki

Weak gravitational lensing by the large scale structure can be used to probe the dark matter distribution in the Universe directly and thus to probe cosmological models. The recent detection of cosmic shear by several groups has…

Astrophysics · Physics 2011-05-23 P. Schneider , L. van Waerbeke , Y. Mellier

Subject of this paper is the weak lensing effect on galaxies that show intrinsically correlated ellipticities. In our model, we investigate the distortion of the ellipticity field if the galaxies experience an apparent shift in their…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Aram Giahi-Saravani , Bjoern Malte Schaefer

The effect of weak gravitational lensing on the cosmic microwave background (CMB) temperature anisotropies and polarization will provide access to cosmological information that cannot be obtained from the primary anisotropies alone. We…

Astrophysics · Physics 2007-05-23 Sarah Smith , Anthony Challinor , Graca Rocha

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

Weak gravitational lensing is one of the key probes of cosmology. Cosmic shear surveys aimed at measuring the distribution of matter in the universe are currently being carried out (Pan-STARRS) or planned for the coming decade (DES, LSST,…

Cosmology and Nongalactic Astrophysics · Physics 2013-11-22 Alberto Vallinotto

Weak gravitational lensing of distant galaxies by foreground structures has proven to be a powerful tool to study the mass distribution in the universe. Nowadays, attention has shifted from clusters of galaxies to the statistical properties…

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

We study the estimators of various second-order weak lensing statistics such as the shear correlation functions xi_\pm and the aperture mass dispersion <M_ap^2> which can directly be constructed from weak lensing shear maps. We compare the…

Astrophysics · Physics 2009-11-13 Martin Kilbinger , Dipak Munshi

Hu [Phys. Rev. D62 (2000) 043007] has presented a harmonic-space method for calculating the effects of weak gravitational lensing on the cosmic microwave background (CMB) over the full sky. Computing the lensed power spectra to first order…

Astrophysics · Physics 2009-11-07 Anthony Challinor , Gayoung Chon

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

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

We measure seeing-corrected ellipticities for 2 x 10^6 galaxies with magnitude R<23 in 12 widely separated fields totalling 75 deg^2 of sky. At angular scales >30\arcmin, ellipticity correlations are detected at high significance and…

Astrophysics · Physics 2015-06-24 M. Jarvis , G. Bernstein , B. Jain , P. Fischer , D. Smith , J. A. Tyson , D. Wittman
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