English
Related papers

Related papers: Twist and Turn: Weak Lensing Image Distortions to …

200 papers

We present an algorithm to estimate the rotation pole of a principal-axis rotator using silhouette images collected from multiple camera poses. First, a set of images is stacked to form a single silhouette-stack image, where the object's…

Computer Vision and Pattern Recognition · Computer Science 2025-02-06 Jacopo Villa , Jay W. McMahon , Issa A. D. Nesnas

As gravitational lensing measurements become increasingly precise, it becomes necessary to include ever higher order effects in the theoretical calculations. Here we show how the difference between the shear and the reduced shear manifest…

Astrophysics · Physics 2008-11-26 Martin White

The angular correlation function \wth of faint galaxies is affected both by nonlinear gravitational evolution and by magnification bias due to gravitational lensing. We compute the resulting \wth for different cosmological models and show…

Astrophysics · Physics 2020-11-25 R. Moessner , B. Jain , J. V. Villumsen

Second-order measures, such as the two-point correlation function, are geometrical quantities describing the clustering properties of a point distribution. In this article well-known estimators for the correlation integral are reviewed and…

Astrophysics · Physics 2007-05-23 Martin Kerscher

When the gravitational lensing of the large-scale structure is calculated from a cosmological model a few assumptions enter: $(i)$ one assumes that the photons follow unperturbed background geodesics, which is usually referred to as the…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-28 Carolina Cuesta-Lazaro , Arnau Quera-Bofarull , Robert Reischke , Bjoern Malte Schaefer

Dark matter caustics have specific density profiles and, therefore, precisely calculable gravitational lensing properties. We present a formalism which simplifies the relevant calculations, and apply it to four specific cases. In the first…

Astrophysics · Physics 2009-11-07 C. Charmousis , V. Onemli , Z. Qiu , P. Sikivie

We discuss novel features of twisted-light absorption both by hydrogen-like atoms and by micro-particles. First, we extend the treatment of atomic photoexcitation by twisted photons to include atomic recoil, derive generalized quantum…

Quantum Physics · Physics 2014-10-17 Andrei Afanasev , Carl E. Carlson , Asmita Mukherjee

Matter near a gravitational lens galaxy or projected along the line of sight (LOS) can affect strong lensing observables by more than contemporary measurement errors. We simulate lens fields with realistic three-dimensional mass…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-12 Curtis McCully , Charles R. Keeton , Kenneth C. Wong , Ann I. Zabludoff

Exotic objects such as the Ellis wormhole are expected to act as gravitational lenses. Much like their nonexotic counterparts, information about these lenses can be found by considering the strong and weak lensing fields they induce. In…

General Relativity and Quantum Cosmology · Physics 2022-09-12 Evan J. Arena

We present a framework for analyzing weak gravitational lensing survey data, including lensing and source-density observables, plus spectroscopic redshift calibration data. All two-point observables are predicted in terms of parameters of a…

Astrophysics · Physics 2014-11-18 Gary M. Bernstein

Gravitational flexion, caused by derivatives of the gravitational tidal field, is potentially important for the analysis of the dark-matter distribution in gravitational lenses, such as galaxy clusters or the dark-matter haloes of galaxies.…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Massimo Viola , Peter Melchior , Matthias Bartelmann

We introduce a novel approach for detecting gravitational waves through their influence on the shape of resolved astronomical objects. This method, complementary to pulsar timing arrays and astrometric techniques, explores the…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-22 Giorgio Mentasti , Carlo R. Contaldi

When the gravitational lensing potential can be approximated by that of circularly symmetric system affected by weak perturbations, it is found that the shape of the resulting (tangential) caustics is entirely specified by the local…

Astrophysics · Physics 2007-05-23 Jin H. An

We present an optical tweezer based study of rotation of microscopic objects with shape asymmetry. Thermal fluctuations and rotations are simultaneously monitored through laser back scattering. The rotation results in a modulation in…

Soft Condensed Matter · Physics 2011-02-16 Yogesha , Sarbari Bhattacharya , Sharath Ananthamurthy

Harmonic measurements of the longitudinal and transverse voltages in Bi-Sb/Co bilayers are presented. A large second harmonic voltage signal due to the ordinary Nernst effect is observed. In experiments where a magnetic field is rotated in…

Mesoscale and Nanoscale Physics · Physics 2019-05-08 Niklas Roschewsky , Emily S. Walker , Praveen Gowtham , Sarah Muschinske , Frances Hellman , Seth R. Bank , Sayeef Salahuddin

We present formal expressions for the optical scalars in terms of the curvature scalars in the weak gravitational lensing regime at second order in perturbations of a flat background without mentioning the extension of the lens or their…

General Relativity and Quantum Cosmology · Physics 2018-04-16 Gabriel Crisnejo , Emanuel Gallo

A less studied numerical characteristic of periodic orbits of area preserving twist maps of the annulus is the twist or torsion number, called initially the amount of rotation. It measures the average rotation of tangent vectors under the…

Dynamical Systems · Mathematics 2013-09-11 Emilia Petrisor

Image stitching algorithms often adopt the global transformation, such as homography, and work well for planar scenes or parallax free camera motions. However, these conditions are easily violated in practice. With casual camera motions,…

Computer Vision and Pattern Recognition · Computer Science 2017-02-28 Tianzhu Xiang , Gui-Song Xia , Liangpei Zhang

After a brief introduction to gravitational lensing theory, a rough overview of the types of gravitational lensing statistics that have been performed so far will be given. I shall then concentrate on recent results of galaxy-galaxy…

Astrophysics · Physics 2021-04-28 Norbert Straumann

Weak gravitational lensing of distant galaxies by foreground structures has proven to be a powerful tool to study the mass distribution in the universe. Nowadays, attention has shifted from clusters of galaxies to the statistical properties…

Astrophysics · Physics 2009-11-07 Henk Hoekstra , Howard Yee , Mike Gladders