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(shortened) We determine the transformation matrix T that maps multiple images with resolved features onto one another and that is based on a Taylor-expanded lensing potential close to a point on the critical curve within our…

Cosmology and Nongalactic Astrophysics · Physics 2018-05-16 Jenny Wagner , Nicolas Tessore

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

(Abridged) Weak gravitational lensing induces distortions on the images of background galaxies, and thus provides a direct measure of mass fluctuations in the universe. Since the distortions induced by lensing on the images of background…

Astrophysics · Physics 2009-10-31 David Bacon , Alexandre Refregier , Douglas Clowe , Richard Ellis

In this paper, the multiple-source ellipsoidal localization problem based on acoustic energy measurements is investigated via set-membership estimation theory. When the probability density function of measurement noise is…

Information Theory · Computer Science 2019-11-19 Fanqin Meng , Xiaojing Shen , Zhiguo Wang , Haiqi Liu , Junfeng Wang , Yunmin Zhu , Pramod K. Varshney

In this paper we propose a finite element method for solving elliptic equations with the observational Dirichlet boundary data which may subject to random noises. The method is based on the weak formulation of Lagrangian multiplier. We show…

Numerical Analysis · Mathematics 2017-02-20 Zhiming Chen , Rui Tuo , Wenlong Zhang

We infer gravitational lensing shear and convergence fields from galaxy ellipticity catalogs under a spatial process prior for the lensing potential. We demonstrate the performance of our algorithm with simulated Gaussian-distributed…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-19 Michael D. Schneider , Karen Y. Ng , William A. Dawson , Philip J. Marshall , Joshua Meyers , Deborah J. Bard

We study dynamical models for elliptical galaxies, deriving the projected kinematic profiles in a form that is valid for general surface-brightness profiles and (spherical) total mass profiles, without the need for any explicit…

Astrophysics of Galaxies · Physics 2015-06-18 A. Agnello , N. W. Evans , A. J. Romanowsky

We develop and test a method for measuring the gravitational lensing induced distortion of faint background galaxies. We first describe how we locate the galaxies and measure a 2-component `polarisation' or ellipticity statistic $e_\alpha$…

Astrophysics · Physics 2009-10-16 Nick Kaiser , Gordon Squires , Tom Broadhurst

Unevenly spaced time series are common in astronomy because of the day-night cycle, weather conditions, dependence on the source position in the sky, allocated telescope time, corrupt measurements, for example, or be inherent to the…

Instrumentation and Methods for Astrophysics · Physics 2014-02-03 Lorenzo Rimoldini

Accurate measurement of gravitational shear from images of distant galaxies is one of the most direct ways of studying the distribution of mass in the universe. We describe an implementation of a technique that is based on the shapelets…

Astrophysics · Physics 2009-11-11 Konrad Kuijken

Metacalibration is a state-of-the-art technique for measuring weak gravitational lensing shear from well-sampled galaxy images. We investigate the accuracy of shear measured with metacalibration from fitting elliptical Gaussians to…

Instrumentation and Methods for Astrophysics · Physics 2021-03-03 Arun Kannawadi , Erik Rosenberg , Henk Hoekstra

With the availability of galaxy distance indicators in weak lensing surveys, lensing tomography can be harnessed to constrain the three-dimensional (3D) matter power spectrum over a range of redshift and physical scale. By combining…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Patrick Simon

Nonlinear combinations of direct observables are often used to estimate quantities of theoretical interest. Without sufficient caution, this could lead to biased estimations. An example of great interest is the skewness $S_3$ of the galaxy…

Astrophysics · Physics 2009-10-31 Lam Hui , Enrique Gaztanaga

Uncertainty quantification in image retrieval is crucial for downstream decisions, yet it remains a challenging and largely unexplored problem. Current methods for estimating uncertainties are poorly calibrated, computationally expensive,…

Computer Vision and Pattern Recognition · Computer Science 2021-09-20 Frederik Warburg , Martin Jørgensen , Javier Civera , Søren Hauberg

We introduce a novel method for weak-lensing measurements, which is based on a mathematically exact deconvolution of the moments of the apparent brightness distribution of galaxies from the telescope's PSF. No assumptions on the shape of…

Instrumentation and Methods for Astrophysics · Physics 2012-04-24 Peter Melchior , Massimo Viola , Björn Malte Schäfer , Matthias Bartelmann

Given 2D point correspondences between an image pair, inferring the camera motion is a fundamental issue in the computer vision community. The existing works generally set out from the epipolar constraint and estimate the essential matrix,…

Computer Vision and Pattern Recognition · Computer Science 2025-08-21 Guangyang Zeng , Qingcheng Zeng , Xinghan Li , Biqiang Mu , Jiming Chen , Ling Shi , Junfeng Wu

We present a new approach to measure the mass function of dark matter halos and to discriminate models with differing values of Omega through weak gravitational lensing. We measure the distribution of peaks from simulated lensing surveys…

Astrophysics · Physics 2009-10-31 Bhuvnesh Jain , Ludovic Van Waerbeke

Anomaly detection is a field of intense research. Identifying low probability events in data/images is a challenging problem given the high-dimensionality of the data, especially when no (or little) information about the anomaly is…

Machine Learning · Computer Science 2022-04-13 José A. Padrón-Hidalgo , Valero Laparra , Gustau Camps-Valls

We demonstrate a method for reconstructing the weak lensing potential from the Lyman-$\alpha$ forest data. We derive an optimal estimator for the lensing potential on the sky based on the correlation between pixels in real space. This…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-21 R. Benton Metcalf , Nicolas Tessore , Rupert A. C. Croft

Quantifying the uncertainty of an object's pose estimate is essential for robust control and planning. Although pose estimation is a well-studied robotics problem, attaching statistically rigorous uncertainty is not well understood without…

Robotics · Computer Science 2025-11-27 Lorenzo Shaikewitz , Charis Georgiou , Luca Carlone