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

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We explore the stability of the variance and skewness of the cosmic gravitational convergence field, using two different approaches: first we simulate a whole MEGACAM survey (100 sq. degrees). The reconstructed mass map, obtained from a…

Astrophysics · Physics 2007-05-23 A. Thion , Y. Mellier , F. Bernardeau , E. Bertin , T. Erben , L. van Waerbeke

We discuss the amplitude and phase fluctuations of gravitational waves due to wave optics lensing in the presence of both a strong lens and cosmological weak lenses. By applying the geometric optics approximation to the strong lens and…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-03 Yuta Nakazono , Teruaki Suyama

Weak lensing of galaxies by large scale structure can potentially measure cosmological quantities as accurately as the cosmic microwave background (CMB). However, the relation between observables and fundamental parameters is more complex…

Astrophysics · Physics 2009-10-31 Wayne Hu , Max Tegmark

Weak gravitational lensing is responsible for the shearing and magnification of the images of high-redshift sources due to the presence of intervening matter. The distortions are due to fluctuations in the gravitational potential, and are…

Astrophysics · Physics 2009-09-29 D. Munshi , P. Valageas , L. Van Waerbeke , A. Heavens

Residual errors in shear measurements, after corrections for instrument systematics and atmospheric effects, can impact cosmological parameters derived from weak lensing observations. Here we combine convergence maps from our suite of…

Cosmology and Nongalactic Astrophysics · Physics 2015-01-06 Andrea Petri , Morgan May , Zoltan Haiman , Jan M. Kratochvil

Weak gravitational lensing is now established as a powerful method to measure mass fluctuations in the universe. It relies on the measurement of small coherent distortions of the images of background galaxies. Even low-level correlations in…

Astrophysics · Physics 2009-07-09 Alan Heavens , Alexandre Refregier , Catherine Heymans

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

Analytical expressions for covariances of weak lensing statistics related to the aperture mass $\Map$ are derived for realistic survey geometries such as SNAP for a range of smoothing angles and redshift bins. We incorporate the…

Astrophysics · Physics 2009-11-10 Dipak Munshi , Patrick Valageas

Weak lensing is commonly measured using shear through galaxy ellipticities, or using the effect of magnification bias on galaxy number densities. Here, we report on the first detection of weak lensing magnification with a new, independent…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-19 Fabian Schmidt , Alexie Leauthaud , Richard Massey , Jason Rhodes , Matthew R. George , Anton M. Koekemoer , Alexis Finoguenov , Masayuki Tanaka

Standard cosmological weak lensing analyses using cosmic shear are inevitably sensitive to small-scale, non-linear clustering from low-redshift structures. The need to adequately model the clustering of matter on this non-linear regime,…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-25 Giulia Piccirilli , Matteo Zennaro , Carlos García-García , David Alonso

High peaks in weak lensing (WL) maps originate dominantly from the lensing effects of single massive halos. Their abundance is therefore closely related to the halo mass function and thus a powerful cosmological probe. On the other hand,…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-24 Shuo Yuan , Xiangkun Liu , Chuzhong Pan , Qiao Wang , Zuhui Fan

Imaging systematics refers to the inhomogeneous distribution of a galaxy sample caused by varying observing conditions and astrophysical foregrounds. Current mitigation methods correct the galaxy density fluctuations caused by imaging…

All models of dynamical dark energy possess fluctuations, which affect the number of galaxy clusters in the Universe. We have studied the impact of dark energy clustering on the number of clusters using a generalization of the spherical…

Cosmology and Nongalactic Astrophysics · Physics 2009-08-05 L. Raul Abramo , Ronaldo C. Batista , Rogerio Rosenfeld

Band-resolved frequency modulation spectroscopy is a common method to measure weak signals of radiative ensembles. When the optical depth of the medium is large, the signal drops exponentially and the technique becomes ineffective. In this…

In this paper, we investigate the impact of higher-order distortions on the precise measurement of weak gravitational lensing shear and flexion. We begin by defining generalized higher-order distortions and outlining methods for measuring…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-01 Yuki Okura , Toshifumi Futamase

We discuss how small-scale density perturbations on the Fresnel scale affect amplitudes and phases of gravitational waves that are magnified by gravitational lensing in geometric optics. We derive equations that connect the small-scale…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-07 Masamune Oguri , Ryuichi Takahashi

We investigate weak lensing by large-scale structure using ray tracing through N-body simulations. Photon trajectories are followed through high resolution simulations of structure formation to make simulated maps of shear and convergence…

Astrophysics · Physics 2009-09-25 Bhuvnesh Jain , Uros Seljak , Simon White

We investigate the weak lensing effects of line-of-sight structures on quadruple images in quasar-galaxy strong lens systems based on N-body and ray-tracing simulations that can resolve halos with a mass of 10^5 solar mass. The intervening…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Ryuichi Takahashi , Kaiki Taro Inoue

Weak Gravitational Lensing is a powerful probe of the dark sector of the Universe. One of the main challenges for this technique is the treatment of systematics in the measurement of cosmic shear from galaxy shapes. In an earlier work,…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-15 Claudio Bruderer , Andrina Nicola , Adam Amara , Alexandre Refregier , Jörg Herbel , Tomasz Kacprzak

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
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