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Related papers: Caustics of Compensated Spherical Lens Models

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We study in detail the trajectories followed by single images during binary microlensing events. Starting from perturbative resolutions of the lens equation, we explore the full parameter space by continuity arguments. We see that the…

Astrophysics · Physics 2009-11-06 V. Bozza

The possibility of using lensed relativistic jets on very small angular scales to construct proper models of spiral lens galaxies and to independently determine the Hubble constant is considered. The system B0218+357 is used as an example…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 T. I. Larchenkova , N. S. Lyskova , A. A. Lutovinov

Only galaxies bright enough and large enough to be unambiguously identified and measured are included in galaxy surveys used to estimate cosmic shear. We demonstrate that because gravitational lensing can scatter galaxies across the…

Cosmology and Nongalactic Astrophysics · Physics 2009-08-17 Fabian Schmidt , Eduardo Rozo , Scott Dodelson , Lam Hui , Erin Sheldon

It is common in Physiological Optics to fit the corneal and the lens surfaces to conic-based surfaces (usually ellipse-based surfaces), obtaining their characteristic radius of curvature and asphericity. Here we show that the variation in…

Medical Physics · Physics 2011-05-03 Alfonso Pérez-Escudero , Carlos Dorronsoro , Susana Marcos

For suitable gravitational lens systems with unknown lens redshifts, the redshifts and brightnesses (in different colours) of the lenses are predicted for a variety of cosmological models, for both elliptical and spiral galaxy lenses.…

Astrophysics · Physics 2007-05-23 Phillip Helbig

The long-standing problem of whether the cosmological constant affects directly the deflection of light caused by a gravitational lens is reconsidered. We use a new approach based on the Hawking quasilocal mass of a sphere grazed by light…

General Relativity and Quantum Cosmology · Physics 2017-01-25 Valerio Faraoni , Marianne Lapierre-Leonard

By directly probing mass distributions, gravitational lensing offers several new tests of the CDM paradigm. Lens statistics place upper limits on the dark matter content of elliptical galaxies. Galaxies built from CDM mass distributions are…

Astrophysics · Physics 2007-05-23 Charles R. Keeton

Strong gravitational lensing has to deal with many modeling degeneracies, the most notable being the Mass Sheet Degeneracy (MSD). We review the MSD when one needs to model more lens planes, each one with an internal mass sheet. We take into…

Astrophysics of Galaxies · Physics 2026-04-03 Luca Teodori

The increasingly large numbers of multiple images in cluster-scale gravitational lenses have allowed for tighter constraints on the mass distributions of these systems. Most lens models have progressed alongside this increase in image…

We investigate the spectro-photometric variability of quasars due to lensing of small mass substructure (from several tens to several hundreds solar masses). The aim of this paper is to explore the milli/microlensing influence on the flux…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Luka C . Popović , Sasa Simić

We discuss the contribution to the characteristic lensing quantities, i.e. the deflection angle and Einstein radius, due to the higher order terms (e.g. the gravitomagnetic terms) considered in the lens potential. The cases we analyze are…

Astrophysics · Physics 2011-01-27 Salvatore Capozziello , Virginia Re

Recent analyses show that $\Lambda$CDM-based models optimised to reproduce the clustering of massive galaxies overestimate their gravitational lensing by about 30\%, the so-called lensing is low problem. Using a state-of-the-art…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-15 Jonas Chaves-Montero , Raul E. Angulo , Sergio Contreras

The micro-arcsecond scale structure of the seemingly point-like images in lensed quasars, though unobservable, is nevertheless much studied theoretically, because it affects the observable (or macro) brightness, and through that provides…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Prasenjit Saha , Liliya L. R. Williams

We formulate a causal extension to the recently introduced paradigm of instance-wise feature selection to explain black-box visual classifiers. Our method selects a subset of input features that has the greatest causal effect on the models…

Machine Learning · Computer Science 2021-04-27 Pranoy Panda , Sai Srinivas Kancheti , Vineeth N Balasubramanian

We discuss how different cosmological models of the Universe affect the probability that a background source has multiple images related by an angular distance $\theta_E$ of the line of sight, \textit{i. e.}, the optical depth of…

Cosmology and Nongalactic Astrophysics · Physics 2013-12-09 R. C. Freitas , S. V. B. Gonçalves , A. M. Oliveira

Strong gravitational lensing offers constraints on the Hubble constant that are independent of other methods. However, those constraints are subject to uncertainties in lens models. Previous studies suggest that using an elliptical power…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-02 Dilys Ruan , Charles R. Keeton

Under the perturbative picture of planetary microlensing, the planet is considered to act as a uniform-shear Chang-Refsdal lens on one of the two images produced by the host star that comes close to the angular Einstein radius of the…

Earth and Planetary Astrophysics · Physics 2023-06-09 Keming Zhang

In this paper we investigate the impact that realistic scale-dependence systematic effects may have on cosmic shear tomography. We model spatially varying residual ellipticity and size variations in weak lensing measurements and propagate…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-09 T. D. Kitching , A. N. Taylor , M. Cropper , H. Hoekstra , R. K. E. Hood , R. Massey , S. Niemi

Gravitational lensing in wave optics is a rich field combining caustic singularities, general relativity and interference phenomena. We present a detailed evaluation of wave optics effects resulting from the frame-dragging of a rotating…

General Relativity and Quantum Cosmology · Physics 2024-10-08 Béatrice Bonga , Job Feldbrugge , Ariadna Ribes Metidieri

Using numerical simulations of cluster formation in the standard CDM model (SCDM) and in a low-density, flat CDM model with a cosmological constant (LCDM), we investigate the gravitational lensing explanation for the reported associations…

Astrophysics · Physics 2009-10-30 Xiang-Ping Wu , Xiao-Hong Zhu , Yi-Peng Jing , Li-Zhi Fang
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