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Related papers: Weak Lensing Mass Reconstruction using Wavelets

200 papers

Motivated by the limitations encountered with the commonly used direct reconstruction techniques of producing mass maps, we have developed a multi-resolution maximum-likelihood reconstruction method for producing two dimensional mass maps…

Astrophysics · Physics 2009-11-13 H. Khiabanian , I. P. Dell'Antonio

We introduce a novel approach to reconstruct dark matter mass maps from weak gravitational lensing measurements. The cornerstone of the proposed method lies in a new modelling of the matter density field in the Universe as a mixture of two…

Cosmology and Nongalactic Astrophysics · Physics 2021-05-26 J. -L. Starck , K. E. Themelis , N. Jeffrey , A. Peel , F. Lanusse

We develop the maximum-entropy weak shear mass reconstruction method presented in earlier papers by taking each background galaxy image shape as an independent estimator of the reduced shear field and incorporating an intrinsic smoothness…

Astrophysics · Physics 2009-11-07 P. J. Marshall , M. P. Hobson , S. F. Gull , S. L. Bridle

We propose a new mass-mapping algorithm, specifically designed to recover small-scale information from a combination of gravitational shear and flexion. Including flexion allows us to supplement the shear on small scales in order to…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-08 Francois Lanusse , Jean-Luc Starck , Adrienne Leonard , Sandrine Pires

Weak lensing, which is the deflection of light by matter along the line of sight, has proven to be an efficient method for constraining models of structure formation and reveal the nature of dark energy. So far, most weak-lensing studies…

We develop an algorithm for the reconstruction of the two-dimensional mass distribution of a gravitational lens from the observable distortion of background galaxies. From the measured reduced shear, the lens mapping is obtained, from which…

Astrophysics · Physics 2009-10-31 Tarun Deep Saini , Somak Raychaudhury

With increasingly large data sets, weak lensing measurements are able to measure cosmological parameters with ever greater precision. However this increased accuracy also places greater demands on the statistical tools used to extract the…

Astrophysics · Physics 2015-05-13 S. Pires , J. -L. Starck , A. Amara , R. Teyssier , A. Refregier , J. Fadili

Modeling the mass distribution of galaxy-scale strong gravitational lenses is a task of increasing difficulty. The high-resolution and depth of imaging data now available render simple analytical forms ineffective at capturing lens…

Instrumentation and Methods for Astrophysics · Physics 2022-12-21 Aymeric Galan , Georgios Vernardos , Austin Peel , Frédéric Courbin , Jean-Luc Starck

We present a concept study on weak lensing map reconstruction through the cosmic magnification effect in galaxy number density distribution. We propose a minimal variance linear estimator to minimize both the dominant systematical and…

Cosmology and Nongalactic Astrophysics · Physics 2012-02-16 Xinjuan Yang , Pengjie Zhang

Weak lensing mass-mapping is a useful tool to access the full distribution of dark matter on the sky, but because of intrinsic galaxy ellipticies and finite fields/missing data, the recovery of dark matter maps constitutes a challenging…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-05 Benjamin Remy , Francois Lanusse , Niall Jeffrey , Jia Liu , Jean-Luc Starck , Ken Osato , Tim Schrabback

Wavelet functions allow the sparse and efficient representation of a signal at different scales. Recently the application of wavelets to the denoising of maps of cosmic microwave background (CMB) fluctuations has been proposed. The…

Astrophysics · Physics 2009-11-07 Klaus Maisinger , M. P. Hobson , A. N. Lasenby

We apply a mass reconstruction technique to simulated large-scale structure gravitational distortion maps, from 2.5' to 10 degree scales, for different cosmological scenarii. The projected mass is reconstructed using a non-parametric least…

Astrophysics · Physics 2007-05-23 L. Van Waerbeke , F. Bernardeau , Y. Mellier

We introduce a novel method for reconstructing the projected matter distributions of galaxy clusters with weak-lensing (WL) data based on convolutional neural network (CNN). Training datasets are generated with ray-tracing through…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-30 Sungwook E. Hong , Sangnam Park , M. James Jee , Dongsu Bak , Sangjun Cha

To derive the convergence field from the gravitational shear (gamma) of the background galaxy images, the classical methods require a convolution of the shear to be performed over the entire sky, usually expressed thanks to the Fast Fourier…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 E. Deriaz , J. -L. Starck , S. Pires

Weak gravitational lensing is considered to be one of the most powerful tools to study the mass and the mass distribution of galaxy clusters. However, the mass-sheet degeneracy transformation has limited its success. We present a novel…

Astrophysics · Physics 2007-05-23 M. Bradac , P. Schneider , M. Lombardi , T. Erben

We present the first reconstruction of dark matter maps from weak lensing observational data using deep learning. We train a convolution neural network (CNN) with a Unet based architecture on over $3.6\times10^5$ simulated data realizations…

Cosmology and Nongalactic Astrophysics · Physics 2020-02-26 Niall Jeffrey , François Lanusse , Ofer Lahav , Jean-Luc Starck

Traditional weak-lensing mass reconstruction techniques suffer from various artifacts, including noise amplification and the mass-sheet degeneracy. In Hong et al. (2021), we demonstrated that many of these pitfalls of traditional mass…

Astrophysics of Galaxies · Physics 2025-02-27 Sangjun Cha , M. James Jee , Sungwook E. Hong , Sangnam Park , Dongsu Bak , Taehwan kim

We present a new method for reconstructing two-dimensional mass maps of galaxy clusters from the image distortion of background galaxies. In contrast to most previous approaches, which directly convert locally averaged image ellipticities…

Astrophysics · Physics 2007-05-23 Stella Seitz , Peter Schneider , Matthias Bartelmann

In this paper, we compare three methods to reconstruct galaxy cluster density fields with weak lensing data. The first method called FLens integrates an inpainting concept to invert the shear field with possible gaps, and a multi-scale…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Eric Jullo , Sandrine Pires , Mathilde Jauzac , Jean-Paul Kneib

The sensitivity and wide area reached by ongoing and future wide-field optical surveys allows for the detection of an increasing number of galaxy clusters uniquely through their weak lensing (WL) signal. This motivates the development of…

Cosmology and Nongalactic Astrophysics · Physics 2023-10-18 G. Leroy , S. Pires , G. W. Pratt , C. Giocoli
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