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Related papers: FASTLens (FAst STatistics for weak Lensing) : Fast…

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Different options can be used in order to measure the shear from observations in the context of weak lensing. Here we introduce new methods where the isotropy assumption for the distribution of the source galaxies is implemented directly on…

Astrophysics · Physics 2008-02-03 Marco Lombardi , Giuseppe Bertin

We measure the distribution of matter contained within the emptiest regions of the Universe: cosmic voids. We use the large overlap between the Ultraviolet Near-Infrared Optical Northern Survey (UNIONS) and voids identified in the LOWZ and…

We present an end-to-end methodology to measure the effects of weak lensing on individual galaxy-galaxy systems exploiting their kinematic information. Using this methodology, we have measured a shear signal from the velocity fields of 18…

Astrophysics of Galaxies · Physics 2020-09-22 Pol Gurri , Edward N. Taylor , Christopher J. Fluke

Medical experts often manually segment images to obtain diagnostic statistics and discard the resulting annotations. We aim to train segmentation models to alleviate this burden, but constrained to the retained summary statistics (e.g., the…

Computer Vision and Pattern Recognition · Computer Science 2026-05-06 Omkar Kulkarni , Edward Raff , Tim Oates

Current constraints on dark matter density profiles from weak lensing are typically limited to radial scales greater than 50-100 kpc. In this paper, we explore the possibility of probing the very inner regions of galaxy/halo density…

Cosmology and Nongalactic Astrophysics · Physics 2015-04-15 Masato I. N. Kobayashi , Alexie Leauthaud , Surhud More , Nobuhiro Okabe , Clotilde Laigle , Jason Rhodes , Tsutomu T. Takeuchi

The existence of galaxy intrinsic clustering severely hampers the weak lensing reconstruction from cosmic magnification. In paper I \citep{Yang2011}, we proposed a minimal variance estimator to overcome this problem. By utilizing the…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-21 Xinjuan Yang , Pengjie Zhang , Jun Zhang , Yu Yu

Weak gravitational lensing has proven to be a powerful tool to map directly the distribution of dark matter in the Universe. The technique, currently used, relies on the accurate measurement of the gravitational shear that corresponds to…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 S. Pires , A. Amara

This is the third in a series of papers that develop a new and flexible model to predict weak-lensing (WL) peak counts, which have been shown to be a very valuable non-Gaussian probe of cosmology. In this paper, we compare the cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-03 Chieh-An Lin , Martin Kilbinger , Sandrine Pires

We use statistical inference theory to explore the constraints from future galaxy weak lensing (cosmic shear) surveys combined with the current CMB constraints on cosmological parameters, focusing particularly on the running of the spectral…

Astrophysics · Physics 2009-11-10 Mustapha Ishak , Christopher M. Hirata , Patrick McDonald , Uros Seljak

We present a quantitative analysis of the largest contiguous maps of projected mass density obtained from gravitational lensing shear. We use data from the 154 deg2 covered by the Canada-France-Hawaii Telescope Lensing Survey. Our study is…

Weak gravitational lensing, the deflection of light by mass, is one of the best tools to constrain the growth of cosmic structure with time and reveal the nature of dark energy. I discuss the sources of systematic uncertainty in weak…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-17 Rachel Mandelbaum

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 estimate uncertainties of cosmological parameters for phenomenological interacting dark energy models using weak lensing convergence power spectrum and bispectrum. We focus on the bispectrum tomography and examine how well the weak…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-31 Rui An , Chang Feng , Bin Wang

In this talk I review some of the key questions that weak lensing observations of clusters can potentially answer, and sketch the progress that has been made to date in extracting quantitative estimates of masses and density profiles. A…

Astrophysics · Physics 2007-05-23 Nick Kaiser

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

The developments summarized with the name ``weak gravitational lensing'' have led to exciting possibilities to study the (statistical properties of the) dark matter distribution in the Universe. Concentrating on those aspects which require…

Astrophysics · Physics 2007-05-23 Peter Schneider , Jean-Paul Kneib

Weak lensing surveys are expected to provide direct measurements of the statistics of the projected dark matter distribution. Most analytical studies of weak lensing statistics have been limited to quasilinear scales as they relied on…

Astrophysics · Physics 2009-10-31 Dipak Munshi , Bhuvnesh Jain

Next generation probes of dark matter and dark energy require high precision reconstruction of faint galaxy shapes from hundreds of dithered exposures. Current practice is to stack the images. While valuable for many applications, this…

Astrophysics · Physics 2008-08-27 J. A. Tyson , C. Roat , J. Bosch , D. Wittman

We develop a method for estimating the shear power spectra from weak lensing observations and test it on simulated data. Our method describes the shear field in terms of angular power spectra and cross correlation of the two shear modes…

Astrophysics · Physics 2008-11-26 Wayne Hu , Martin White

Upcoming surveys such as \LSST{} and \Euclid{} will significantly improve the power of weak lensing as a cosmological probe. To maximise the information that can be extracted from these surveys, it is important to explore novel statistics…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-18 Christopher T. Davies , Marius Cautun , Benjamin Giblin , Baojiu Li , Joachim Harnois-Déraps , Yan-Chuan Cai