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Related papers: Cosmic shear calibration with forward modeling

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We investigate biases induced by the conversion between the observed image shape to shear distortion in current weak lensing analysis methods. Such overall calibration biases cannot be detected by the standard tests such as E/B…

Astrophysics · Physics 2009-11-07 Christopher M. Hirata , Uros Seljak

Weak lensing studies typically require excellent seeing conditions for the purpose of maximizing the number density of well-resolved galaxy images. It is interesting to ask to what extent the seeing size limits the usefulness of the…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-14 Jun Zhang , Cong Liu , Pedro Alonso Vaquero , Hekun Li , Haoran Wang , Zhi Shen , Fuyu Dong

We present the results of weak gravitational lensing statistics in four different cosmological $N$-body simulations. The data has been generated using an algorithm for the three-dimensional shear, which makes use of a variable softening…

Astrophysics · Physics 2009-10-31 Andrew J. Barber , Peter A. Thomas , H. M. P. Couchman , C. J. Fluke

Using the linear theory of perturbations in General Relativity, we express a set of consistency relations that can be observationally tested with current and future large scale structure surveys. We then outline a stringent…

Astrophysics · Physics 2009-11-13 Yong-Seon Song , Olivier Doré

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

We present a study of weak lensing shear measurements for simulated galaxy images at radio wavelengths. We construct a simulation pipeline into which we can input galaxy images of known ellipticity, and with which we then simulate…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Prina Patel , Filipe B. Abdalla , David J. Bacon , Barnaby Rowe , Oleg Smirnov , Rob J. Beswick

When a luminous source is extended, its distortions by weak gravitational lensing are richer than a mere combination of magnification and shear. In a recent work, we proposed an elegant formalism based on complex analysis to describe and…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-29 Pierre Fleury , Julien Larena , Jean-Philippe Uzan

We investigate the problem of noise bias in maximum likelihood and maximum a posteriori estimators for cosmic shear. We derive the leading and next-to-leading order biases and compute them in the context of galaxy ellipticity measurements,…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-23 Alex Hall , Andy Taylor

We present a numerical investigation of nonlinear cluster lens reconstruction using weak lensing mass mapping. Recent advances in imaging and shear estimation have pushed reliable reduced shear measurements closer to cluster cores, making…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-23 Yuan Shi , Li Cui

We describe a new method for measuring galaxy magnification due to weak gravitational lensing. Our method makes use of a tight scaling relation between galaxy properties that are modified by gravitational lensing, such as apparent size, and…

Cosmology and Nongalactic Astrophysics · Physics 2011-11-07 Eric M. Huff , Genevieve J. Graves

Weak-lensing peak counts provide a straightforward way to constrain cosmology by linking local maxima of the lensing signal to the mass function. Recent applications to data have already been numerous and fruitful. However, the importance…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-13 Chieh-An Lin , Martin Kilbinger

The abundance of peaks in weak gravitational lensing maps is a potentially powerful cosmological tool, complementary to measurements of the shear power spectrum. We study peaks detected directly in shear maps, rather than convergence maps,…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-16 Nicolas Martinet , James G. Bartlett , Alina Kiessling , Barbara Sartoris

We investigate the effects of weak gravitational lensing in the standard Cold Dark Matter cosmology, using an algorithm which evaluates the shear in three dimensions. The algorithm has the advantage of variable softening for the particles,…

Astrophysics · Physics 2009-10-31 Andrew J. Barber , Peter A. Thomas , H. M. P. Couchman

We update the publicly available weak lensing shear measurement algorithm pyRRG for the James Webb Space Telescope, and apply it to UNCOVER DR1 imaging of galaxy cluster Abell 2744. At short wavelengths (< 2.5$\mu$m), shear measurements are…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-31 David R. Harvey , Richard Massey

I present a new algorithm, CALCLENS, for efficiently computing weak gravitational lensing shear signals from large N-body light cone simulations over a curved sky. This new algorithm properly accounts for the sky curvature and boundary…

Cosmology and Nongalactic Astrophysics · Physics 2012-10-15 Matthew R. Becker

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

Measurements of weak gravitational lensing using the cosmic microwave background and the shapes of galaxies have refined our understanding of the late-time history of the Universe. While optical surveys have been the primary source for…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-20 Alba Kalaja , Ian Harrison , William R Coulton

The Red-Sequence Cluster Survey (RCS) is a 100 square degree galaxy cluster survey designed to provide a large sample of optically selected clusters of galaxies with redshifts 0.1<z<1.4. The survey data are also useful for a variety of…

Astrophysics · Physics 2007-05-23 Henk Hoekstra , Howard Yee , Mike Gladders

Cluster-scale strong lensing is a powerful tool for exploring the properties of dark matter and constraining cosmological models. However, due to the complex parameter space, pixelized strong lens modeling in galaxy clusters is…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-07 Yushan Xie , Huanyuan Shan , Nan Li , Ran Li , Eric Jullo , Chen Su , Xiaoyue Cao , Jean-Paul Kneib , Ana Acebron , Mengfan He , Ji Yao , Chunxiang Wang , Jiadong Li , Yin Li

Weak gravitational lensing observations probe the spectrum and evolution of density fluctuations and the cosmological parameters which govern them. The non-linear evolution of large scale structure produces a non-Gaussian signal which is…

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