English
Related papers

Related papers: Large scale systematic signals in weak lensing sur…

200 papers

Weak lensing provides an important route toward collecting samples of clusters of galaxies selected by mass. Subtle systematic errors in image reduction can compromise the power of this technique. We use the B-mode signal to quantify this…

Instrumentation and Methods for Astrophysics · Physics 2015-06-15 Yousuke Utsumi , Satoshi Miyazaki , Margaret J. Geller , Ian P. Dell'Antonio , Masamune Oguri , Michael J. Kurtz , Takashi Hamana , Daniel G. Fabricant

We present the first measurement of weak lensing by large-scale structure on 1-4 degree scales based on the FIRST Radio Survey, a quarter-sky, 20-cm survey produced with the NRAO Very Large Array (VLA). The large angular scales provide an…

Astrophysics · Physics 2009-11-10 Tzu-Ching Chang , Alexandre Refregier , David J. Helfand

Weak gravitational lensing is one of the key probes of the cosmological model, dark energy, and dark matter, providing insight into both the cosmic expansion history and large scale structure growth history. Taking into account a broad…

Cosmology and Nongalactic Astrophysics · Physics 2012-11-12 Sudeep Das , Roland de Putter , Eric V. Linder , Reiko Nakajima

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

In this paper, we study the effects of instrumental systematics on the reconstruction of the deflection angle power spectrum from weak lensing of Cosmic Microwave Background (CMB) temperature and polarization observations. We consider seven…

Cosmology and Nongalactic Astrophysics · Physics 2009-06-30 Meng Su , Amit P. S. Yadav , Matias Zaldarriaga

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

(Abridged) Weak gravitational lensing induces distortions on the images of background galaxies, and thus provides a direct measure of mass fluctuations in the universe. Since the distortions induced by lensing on the images of background…

Astrophysics · Physics 2009-10-31 David Bacon , Alexandre Refregier , Douglas Clowe , Richard Ellis

The LSST survey will provide unprecedented statistical power for measurements of dark energy. Consequently, controlling systematic uncertainties is becoming more important than ever. The LSST observing strategy will affect the statistical…

Cosmic shear tomography has emerged as one of the most promising tools to both investigate the nature of dark energy and discriminate between General Relativity and modified gravity theories. In order to successfully achieve these goals,…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-05 V. F. Cardone , M. Martinelli , E. Calabrese , S. Galli , Z. Huang , R. Maoli , A. Melchiorri , R. Scaramella

We extend the notions of multipole and subsystem symmetries to more general {\it spatially modulated} symmetries. We uncover two instances with exponential and (quasi)-periodic modulations, and provide simple microscopic models in one, two…

Statistical Mechanics · Physics 2021-10-19 Pablo Sala , Julius Lehmann , Tibor Rakovszky , Frank Pollmann

We present new results on the gravitational lensing shear and magnification power spectra obtained from numerical simulations of a flat cosmology with a cosmological constant. These results are of considerable interest since both the shear…

Astrophysics · Physics 2009-11-07 Andrew J. Barber , A. N. Taylor

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

We describe a method for computing the biases that systematic signals introduce in parameter estimation using a simple extension of the Fisher matrix formalism. This allows us to calculate the offset of the best fit parameters relative to…

Astrophysics · Physics 2009-11-13 Adam Amara , Alexandre Refregier

We explore the ability of weak lensing surveys to locate massive clusters. We use both analytic models of dark matter halos and mock weak lensing surveys generated from a large cosmological N-body simulation. The analytic models describe…

Astrophysics · Physics 2009-11-10 Takashi Hamana , Masahiro Takada , Naoki Yoshida

The Shear TEsting Programme (STEP) is a collaborative project to improve the accuracy and reliability of weak lensing measurement, in preparation for the next generation of wide-field surveys. We review sixteen current and emerging shear…

We study the effects of large-scale density fluctuations on strong gravitational lensing. Previous studies have focused mostly on weak lensing, since large-scale structure alone cannot produce multiple images. When a galaxy or cluster acts…

Astrophysics · Physics 2009-10-28 Rennan Bar-Kana

The CMB $B$-mode polarisation signal -- both the primordial gravitational wave signature and the signal sourced by lensing -- is subject to many contaminants from systematic effects. Of particular concern are systematics that result in…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-23 Nialh McCallum , Daniel B. Thomas , Michael L. Brown , Nicolas Tessore

Weak lensing observations have the potential to be even more powerful than cosmic microwave background (CMB) observations in constraining cosmological parameters. However, the practical limits to weak lensing observations are not known.…

Astrophysics · Physics 2009-11-13 D. Wittman

Gravitational lensing of electromagnetic (EM) waves has yielded many profound discoveries across fundamental physics, astronomy, astrophysics, and cosmology. Similar to EM waves, gravitational waves (GWs) can also be lensed. When their…

General Relativity and Quantum Cosmology · Physics 2026-01-28 Zhao-Feng Wu , Otto A. Hannuksela , Martin Hendry , Quynh Lan Nguyen

Selected results on estimating cosmological parameters from simulated weak lensing data with noise are presented. Numerical simulations of ray tracing through N-body simulations have been used to generate shear and convergence maps due to…

Astrophysics · Physics 2007-05-23 Bhuvnesh Jain , Uros Seljak , Simon White