English
Related papers

Related papers: Separating weak lensing and intrinsic alignments u…

200 papers

The weak gravitational lensing of distant galaxies by large-scale structure is expected to become a powerful probe of dark energy. By measuring the ellipticities of large numbers of background galaxies, the subtle gravitational distortion…

Astrophysics · Physics 2014-11-18 Charles Shapiro

We present the theoretical and analytical bases of optimal techniques to measure weak gravitational shear from images of galaxies. We first characterize the geometric space of shears and ellipticity, then use this geometric interpretation…

Astrophysics · Physics 2009-11-06 G. M. Bernstein , M. Jarvis

Cosmic shear is a primary cosmological probe for several present and upcoming surveys investigating dark matter and dark energy, such as Euclid or WFIRST. The probe requires an extremely accurate measurement of the shapes of millions of…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-04 Malte Tewes , Thibault Kuntzer , Reiko Nakajima , Frédéric Courbin , Hendrik Hildebrandt , Tim Schrabback

We present a Bayesian hierarchical inference formalism to study the relation between the properties of dark matter halos and those of their central galaxies using weak gravitational lensing. Unlike traditional methods, this technique does…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-11 Alessandro Sonnenfeld , Alexie Leauthaud

This paper extends the method introduced in Rivi et al. (2016b) to measure galaxy ellipticities in the visibility domain for radio weak lensing surveys. In that paper we focused on the development and testing of the method for the simple…

Instrumentation and Methods for Astrophysics · Physics 2018-04-16 Marzia Rivi , Lance Miller

We present a first attempt to reveal the possible existence of large foreground mass condensations directly responsible for the gravitational magnification of four distant luminous radiosources and one optical QSO. The technique uses a weak…

Astrophysics · Physics 2007-05-23 B. Fort , Y. Mellier , M. Dantel-Fort , H. Bonnet , J. -P. Kneib

Weak gravitational lensing surveys measure the distortion of the image of distant sources due to the deflections of light rays by the fluctuations of the gravitational potential along the line of sight. Since they probe the non-linear…

Astrophysics · Physics 2009-11-13 Dipak Munshi , Patrick Valageas

We estimate and remove the contamination of weak gravitational lensing measurements by the intrinsic alignment of close pairs of galaxies. We do this by investigating both the aperture mass B mode statistic, and the shear correlations of…

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

We explore the sensitivity of weak lensing surveys to gravitational waves (GWs) emitted by inspiraling supermassive black hole binaries (SMBHBs) in the nanohertz to microhertz frequency band, bridging the gap between pulsar timing arrays…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-13 Tal Adi , Kris Pardo , Olivier Doré

The current weak lensing measurements of the large scale structure are mostly related to statistical study of background galaxy ellipticities. We consider a possibility to extend lensing studies with intrinsically unresolved sources and…

Astrophysics · Physics 2008-11-26 Asantha Cooray

The analysis of whole-sky galaxy surveys commonly suffers from the problems of shot-noise and incomplete sky coverage (e.g. at the Zone of Avoidance). The orthogonal set of spherical harmonics is utilized here to expand the observed galaxy…

Astrophysics · Physics 2009-10-22 O. Lahav , K. B. Fisher , Y. Hoffman , C. A. Scharf , S. Zaroubi

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

Point estimators for the shearing of galaxy images induced by gravitational lensing involve a complex inverse problem in the presence of noise, pixelization, and model uncertainties. We present a probabilistic forward modeling approach to…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-15 Michael D. Schneider , David W. Hogg , Philip J. Marshall , William A. Dawson , Joshua Meyers , Deborah J. Bard , Dustin Lang

Weak gravitational lensing has the potential to constrain cosmological parameters to high precision. However, as shown by the Shear TEsting Programmes (STEP) and GRavitational lEnsing Accuracy Testing (GREAT) Challenges, measuring galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Tomasz Kacprzak , Joe Zuntz , Barnaby Rowe , Sarah Bridle , Alexandre Refregier , Adam Amara , Lisa Voigt , Michael Hirsch

Weak lensing experiments are a powerful probe of cosmology through their measurement of the mass distribution of the universe. A challenge for this technique is to control systematic errors that occur when measuring the shapes of distant…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Alexandre Refregier , Tomasz Kacprzak , Adam Amara , Sarah Bridle , Barnaby Rowe

Weak gravitational lensing observations probe the spectrum and evolution of density fluctuations and the cosmological parameters which govern them but are currently limited to small fields and subject to selection biases. We show how the…

Astrophysics · Physics 2009-10-31 Asantha Cooray , Wayne Hu , Jordi Miralda-Escude

Weak gravitational lensing (WL) surveys provide insight into the matter distribution over an extensive range of scales. Current WL results are in mild tension with cosmic microwave background measurements from the early Universe.…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-07 Jeger C. Broxterman , Konrad Kuijken

In the very near future, weak lensing surveys will map the projected density of the universe in an unbiased way over large regions of the sky. In order to interpret the results of studies it is helpful to develop an understanding of the…

Astrophysics · Physics 2008-11-26 Dipak Munshi , Peter Coles
‹ Prev 1 4 5 6 7 8 10 Next ›