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Related papers: Gravitational Lensing by Dark Matter Caustics

200 papers

Weak gravitational lensing seeks to determine shear by measuring induced quadrupole (elliptical) shapes in background galaxy images. Small impact parameter (a few kpc) gravitational lensing by foreground core masses between 2 10^{9} and 2…

Astrophysics · Physics 2014-10-13 John Irwin , Marina Shmakova

The mass of an astrophysical object can be estimated by the amount of gravitational lensing of another object that it causes. To arrive at the estimation however, one assumes the validity of the inverse square law of gravity, or…

General Relativity and Quantum Cosmology · Physics 2023-03-07 Saurya Das , Sourav Sur

Numerical simulations and theoretical studies of the gravitational microlensing effect of a population of small bodies distributed along the line of sight to a compact light source such as a quasar indicate that caustic crossing effects…

Astrophysics · Physics 2007-05-23 M. R. S. Hawkins

Cold dark matter haloes are populated by high-density structures with sharply-peaked profiles known as caustics which have not yet been resolved by 3-dimensional numerical simulations. Here, we derive semi-analytic expressions for the…

Astrophysics · Physics 2009-11-10 Roya Mohayaee , Sergei Shandarin

The gravitational lensing of supermassive black holes surrounded by dark matter halo has attracted a great number of interests in recent years. However, many studies employed simplified dark matter density models, which makes it very hard…

General Relativity and Quantum Cosmology · Physics 2024-10-25 Yi-Gao Liu , Chen-Kai Qiao , Jun Tao

Gravitational microlensing of planetary-mass objects (or "nanolensing", as it has been termed) can be used to probe the distribution of mass in a galaxy that is acting as a gravitational lens. Microlensing and nanolensing light curve…

Astrophysics of Galaxies · Physics 2015-06-03 H. Garsden , N. F. Bate , G. F. Lewis

In these lectures I give an overview of gravitational lensing, concentrating on theoretical aspects, including derivations of some of the important results. Topics covered include the determination of surface mass densities of intervening…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-08 Alan Heavens

The nature of dark matter and dark energy are among the central questions in cosmology. Strong gravitational lenses with multiple source planes provide a geometric probe of cosmology: the ratio of deflection angles at different redshifts…

Weak gravitational lensing observations probe the spectrum and evolution of density fluctuations and the cosmological parameters which govern them. The non-linear evolution of large scale structure produces a non-Gaussian signal which is…

Astrophysics · Physics 2009-10-31 Asantha Cooray , Wayne Hu

Plane-symmetric gravitational waves are considered as gravitational lenses. Numbers of images, frequency shifts, mutual angles, and image distortion parameters are computed exactly in essentially all non-singular plane wave spacetimes. For…

General Relativity and Quantum Cosmology · Physics 2015-06-11 Abraham I. Harte

The magnifications of compact-source lenses are extremely sensitive to the presence of low mass dark matter halos along the entire sight line from the source to the observer. Traditionally, the study of dark matter structure in…

A computer code is described for the simulation of gravitational lensing data. The code incorporates adaptive mesh refinement in choosing which rays to shoot based on the requirements of the source size, location and surface brightness…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-29 R. Benton Metcalf , Margarita Petkova

Galaxy clusters as gravitational lenses play a unique role in astrophysics and cosmology: they permit mapping the dark matter distribution on a range of scales; they reveal the properties of high and intermediate redshift background…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-12 Priyamvada Natarajan , Liliya L. Williams , Marusa Bradac , Claudio Grillo , Agniva Ghosh , Keren Sharon , Jenny Wagner

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

Gravitational lensing time delays offer an avenue to measure the Hubble parameter $H_0$, with some analyses suggesting a tension with early-type probes of $H_0$. The lensing measurements must mitigate systematic uncertainties due to the…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-15 Kfir Blum , Luca Teodori

We discuss strong gravitational lensing by multiple objects along any line of sight. The probability for strong gravitational lensing by more than one lens is small, but a number of strong lens systems in which more than one separate lens…

Astrophysics · Physics 2009-11-06 Ole Moeller , A. W. Blain

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

Magnification of total image fluxes is typically considered a defining feature of gravitational microlensing. In contrast, I will show that nonminimal couplings to gravity can generate regions of negative gravitational potential curvature,…

General Relativity and Quantum Cosmology · Physics 2026-04-03 Hong-Yi Zhang

Traditional estimators of the mass of galaxy clusters assume that the cluster components (galaxies, intracluster medium, and dark matter) are in dynamical equilibrium. Two additional estimators, that do not require this assumption, were…

Cosmology and Nongalactic Astrophysics · Physics 2009-02-02 Antonaldo Diaferio

Dark matter caustics are small scale, high density structures believed to exist in galaxies like ours. If the dark matter consists of Weakly Interacting Massive Particles, these caustics may be detected by means of the gamma rays produced…

Astrophysics · Physics 2008-12-18 Aravind Natarajan , Pierre Sikivie