English
Related papers

Related papers: Gravitational Lensing By a Massive Object in a Dar…

200 papers

We study the gravitational lensing influence of a massive object in a dark matter halo, using a simple model of a point mass embedded in a spherical Navarro--Frenk--White halo. Building on the analysis of critical curves and caustics…

Astrophysics of Galaxies · Physics 2022-03-14 Michal Karamazov , David Heyrovsky

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

In this study, we explore gravitational lensing using more realistic dark matter halo models, moving beyond the limitations of spherical-collapse approximations. Through analytical calculations employing various mass functions, we address…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-13 Ali Tizfahm , Saeed Fakhry , Javad T. Firouzjaee , Antonino Del Popolo

We study strong gravitational lensing by spiral galaxies, modeling them as infinitely thin uniform disks embedded in singular isothermal spheres. We derive general properties of the critical curves and caustics analytically. The…

Astrophysics · Physics 2015-06-24 Yun Wang , Edwin L. Turner

In the context of this paper, microlenses present as oblate clusters of dark matter structures called massive astrophysical compact halo object(MACHO) in the galactic halo are considered. The NFW density profile [1] is derived from the…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-20 Tabib Rayed Hossain , Prabir Kumar Haldar , Mehedi Kalam

If modified gravity holds, but the weak lensing analysis is done in the standard way, one finds that dark matter halos have peculiar shapes, not following the standard Navarro-Frenk-White profiles, and are fully predictable from the…

Astrophysics of Galaxies · Physics 2026-02-20 Michal Bílek

We investigate gravitational lensing by a realistic model of disk galaxies. Most of the mass is contained in a large spherical isothermal dark matter halo, but the potential is modified significantly in the core by a…

Astrophysics · Physics 2009-10-30 Ole Moeller , A. W. Blain

There are two observations of galaxies that can offer some insight into the nature of the dark matter (DM), namely the rotation curves and the gravitational lensing. While the first one can be studied using the Newtonian limit, the second…

Astrophysics of Galaxies · Physics 2014-11-21 Dario Nunez , Alma X. Gonzalez Morales , Jorge L. Cervantes-Cota , Tonatiuh Matos

We explore the lowest mass limit that can be placed on the halo mass function in CDM using 28 strong gravitational lenses. For this purpose, we study an extreme model in which the halo mass function and mass-concentration relation follow…

Galactic sized gravitational lenses are simulated by combining a cosmological N-body simulation and models for the baryonic component of the galaxy. The lens caustics, critical curves, image locations and magnification ratios are calculated…

Astrophysics · Physics 2009-11-10 Adam Amara , R. Benton Metcalf , Thomas J. Cox , Jeremiah P. Ostriker

The statistics of wide-separation (6'' < theta < 15'') gravitational lenses constrain the amount of mass in the cores of dark matter halos on group and cluster mass scales. For a family of halo models with a central cusp $\rho \propto…

Astrophysics · Physics 2009-11-06 Charles R. Keeton , Piero Madau

Caustics are high-density structures that form frequently in collisionless media. Under self-gravity, cold dark matter flows focus onto caustics which are yet to be resolved in numerical simulations and or observed in the real world. If…

Astrophysics · Physics 2008-11-26 Raphael Gavazzi , Roya Mohayaee , Bernard Fort

Gravitational lensing is an invaluable probe of the nature of dark matter, and the structures it forms. Lensed gravitational waves in particular allow for unparalleled sensitivity to small scale structures within the lenses, due to the…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-17 Luka Vujeva , Jose María Ezquiaga , Daniel Gilman , Srashti Goyal , Miguel Zumalacárregui

We argue that combined observations of galaxy rotation curves and gravitational lensing not only allow the deduction of a galaxy's mass profile, but also yield information about the pressure in the galactic fluid. We quantify this statement…

Astrophysics · Physics 2008-11-26 Tristan Faber , Matt Visser

Measuring the distribution of mass on galaxy cluster scales is a crucial test of the Lambda CDM model, providing constraints on the nature of dark matter. Recent work investigating mass distributions of individual galaxy clusters using…

Astrophysics · Physics 2009-11-11 V. Corless , L. King

We study gravitational lensing of light by hairy black holes, which, in a certain parameter regime, can possess two photon spheres of different size outside the event horizon. In particular, we focus on higher-order images of a point-like…

General Relativity and Quantum Cosmology · Physics 2022-07-13 Guangzhou Guo , Xin Jiang , Peng Wang , Houwen Wu

Effects of macro-and microlensing on the spatial and temporal characteristics of images of remote sources, observed through the inner regions of lensing galaxies are discussed. A particular attention was given to the case, when microlenses,…

Astrophysics · Physics 2007-05-23 A. A. Minakov , V. G. Vakulik

Measuring the density profile and mass concentration of dark-matter haloes is a key test of the standard cold dark matter paradigm. Such objects are dark and thus challenging to characterise, but they can be studied via gravitational…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-07 S. Vegetti , S. D. M. White , J. P. McKean , D. M. Powell , C. Spingola , D. Massari , G. Despali , C. D. Fassnacht

Dark matter density is formally infinite at the location of caustic surfaces, where dark matter sheet folds in phase space. The caustics separate multi-stream regions with different number of streams. Volume elements change the parity by…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-03 Segei F. Shandarin

There are compelling reasons to believe that the dark matter of the universe is constituted, in large part, by non-baryonic collisionless particles with very small primordial velocity dispersion. Such particles are called cold dark matter…

Astrophysics · Physics 2007-05-23 Vakif K. Onemli
‹ Prev 1 2 3 10 Next ›