English
Related papers

Related papers: Gravitational Lensing by Ring-Like Structures

200 papers

We examine the gravitational lensing effect of a foreground galaxy cluster on the number count statistics of background X-ray sources. The lensing produces a deficit in the number of resolved sources in a ring close to the critical radius…

Astrophysics · Physics 2007-05-23 Alexandre Refregier , Abraham Loeb

The existence of a massive black hole in the center of the Milky Way, coinciding with the radio source Sgr A*, is being established on more and more solid ground. In principle, this black hole, acting as a gravitational lens, is able to…

Astrophysics · Physics 2011-02-11 Valerio Bozza , Luigi Mancini

Recently, Y. Sobouti (2007) has provided a metric theory f(R) that can account for certain dynamical anomalies observed in spiral galaxies. Mendoza & Rosas-Guevara (2007) have shown that in this theory there is an extra-bending as compared…

Astrophysics · Physics 2009-11-13 Tula Bernal , Sergio Mendoza

The transparent Sun is modeled as a spherically symmetric and centrally condensed gravitational lens using recent Standard Solar Model (SSM) data. The Sun's minimum focal length is computed to a refined accuracy of 23.5 +/- 0.1 AU, just…

Astrophysics · Physics 2011-12-13 Bijunath Patla , Robert J. Nemiroff

The two outer triangular caustics (regions of infinite magnification) of a close binary microlens move much faster than the components of the binary themselves, and can even exceed the speed of light. When $\epsilon > 1$, where $\epsilon c$…

Astrophysics · Physics 2009-10-31 Zheng Zheng , Andrew Gould

We introduce the notion of defocusing gravitational lens considering a MACHO located behind a light source with respect to an observer. The consequence of defocusing effect is a temporal variability of star luminosity which produces a gap…

Binary black holes have been in limelight off late due to the detection of gravitational waves from coalescing compact binaries in the events GW150914 and GW151226. In this paper we study gravitational lensing by the binary black holes…

General Relativity and Quantum Cosmology · Physics 2017-01-25 Mandar Patil , Priti Mishra , D. Narasimha

The gravitational lensing constraints on the small mass end of the LCDM mass function are discussed. Here a conservative approach is taken where only the most difficult to explain image flux anomalies in strong QSO lenses are emphasized.…

Astrophysics · Physics 2009-11-10 R. Benton Metcalf

Some aspects of gravitational lensing by large scale structure (LSS) are investigated. We show that lensing causes the damping tail of the cosmic microwave background (CMB) power spectrum to fall less rapidly with decreasing angular scale…

Astrophysics · Physics 2015-06-24 R. Benton Metcalf , Joseph Silk

The theory of gravitational lensing is reviewed from a spacetime perspective, without quasi-Newtonian approximations. More precisely, the review covers all aspects of gravitational lensing where light propagation is described in terms of…

General Relativity and Quantum Cosmology · Physics 2010-10-19 Volker Perlick

In a recent paper [Ruffa] it was proposed that the massive black hole at the Galactic center may act as a gravitational lens focusing gravitational wave energy to the Earth. Considering the gravitational wave signal emitted by galactic…

Astrophysics · Physics 2009-11-07 F. De Paolis , G. Ingrosso , A. A. Nucita , A. Qadir

Strong gravitational lensing gives access to the total mass distribution of galaxies. It can unveil a great deal of information about the lenses dark matter content when combined with the study of the lenses light profile. However,…

Astrophysics of Galaxies · Physics 2017-08-02 Judith Biernaux , Pierre Magain , Clementine Hauret

The gravitational lensing of faint background galaxies by rich clusters is emerging as a very efficient method to constrain both the mass distribution of cluster of galaxies and probe the statistical properties of faint background galaxies.…

Astrophysics · Physics 2007-05-23 J. -P. Kneib , G. Soucail

Multiple images, giant arcs, Einstein cross, fold, cusp, lip, caustics, critical lines, sources, mapping, time delay, arclets, weak shear, magnification bias, depletion, ellipticities, polarization, smearing, convergence, kernel, mass…

Astrophysics · Physics 2007-05-23 Jean-Paul Kneib

We propose a novel concept of astrophysical mirroring in the schwarzschild framework, which emerges as a direct consequence of gravitational lensing effects occurring in the immediate vicinity of extremely dense massive objects within…

General Relativity and Quantum Cosmology · Physics 2026-04-08 Bikramarka S Choudhury , Aritra Sanyal , Md Khalid Hossain , Farook Rahaman

In gravitational microlensing, binary systems may act as lenses or sources. Identifying lens binarity is generally easy especially in events characterized by caustic crossing since the resulting light curve exhibits strong deviations from…

Solar and Stellar Astrophysics · Physics 2016-06-08 A. A. Nucita , F. De Paolis , G. Ingrosso , M. Giordano , L. Manni

Gravitational lenses are a unique new constraint on the structure of galaxies. We review the evidence that most lenses are early-type galaxies, the optical properties of the lens galaxies, the evidence against constant M/L models, recent…

Astrophysics · Physics 2007-05-23 C. S. Kochanek , C. R. Keeton

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

A long standing question in cosmology is whether gravitational lensing changes the distance-redshift relation $D(z)$ or the mean flux density of sources. Interest in this has been rekindled by recent studies in non-linear relativistic…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-16 Nick Kaiser , John A. Peacock

In a gravitational lensing system, the relative transverse velocities of the lens, source, and observer induce a frequency shift in the observed radiation. While this shift is typically negligible in most astrophysical contexts, strategies…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-21 Mikołaj Korzyński , Mateusz Kulejewski