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Related papers: Probing Dark Matter Substructure in Lens Galaxies

200 papers

The goal of this paper is to develop a machine learning model to analyze the main gravitational lens and detect dark substructure (subhalos) within simulated images of strongly lensed galaxies. Using the technique of image segmentation, we…

Cosmology and Nongalactic Astrophysics · Physics 2022-01-27 Bryan Ostdiek , Ana Diaz Rivero , Cora Dvorkin

In this paper, we undertake a study to determine what insight can be reliably gleaned from the comparison of the X-ray and the weak lensing mass maps of galaxy clusters. We do this by investigating the 2D substructure within three…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Leila C. Powell , Scott T. Kay , Arif Babul

We investigate the feasibility of extracting the gravitational nanolensing signal due to the presence of subsolar mass halos within galaxy-sized dark matter halos. We show that subsolar mass halos in a lensing galaxy can cause strong…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-27 Jacqueline Chen , Savvas M. Koushiappas

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

We analyse the impact of galaxy--halo misalignment on the ability of weak lensing studies to constrain the shape of dark matter haloes, using a combination of the Millennium dark matter N-body simulation and different semi-analytic galaxy…

Cosmology and Nongalactic Astrophysics · Physics 2016-07-07 Philip E. Bett

Characterising the population and internal structure of sub-galactic halos is critical for constraining the nature of dark matter. These halos can be detected near galaxies that act as strong gravitational lenses with extended arcs, as they…

While the $\Lambda$CDM model succeeds on large scales, its validity on smaller scales remains uncertain. Recent works suggest that non-halo dark matter structures, such as filaments and walls, could significantly influence gravitational…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-21 Baptiste Jego , Giulia Despali , Tamara Richardson , Jens Stücker

The clustering of galaxies and the matter distribution around them can be described using the halo model complemented with a realistic description of the way galaxies populate dark matter haloes. This has been used successfully to describe…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Marcello Cacciato , Edo van Uitert , Henk Hoekstra

Modified Gravity (MG) scenarios have been advocated to account for the dark energy phenomenon in the universe. These models predict departures from General Relativity on large cosmic scales that can be tested through a variety of probes…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-12 P. S. Corasaniti , C. Giocoli , M. Baldi

Recent Strong lensing data and rotation curves of dwarf galaxies indicate that many galactic clusters may have a soft core instead of a central cusp in their density distribution. This result challenges the standard CDM (Cold Dark Matter)…

Astrophysics · Physics 2007-05-23 M. H. Chan , M. C. Chu

In recent years, gravitational lensing has been used as a means to detect substructure in galaxy-sized halos, via anomalous flux ratios in quadruply-imaged lenses. In addition to causing anomalous flux ratios, substructure may also perturb…

Astrophysics · Physics 2011-02-11 Jacqueline Chen , Eduardo Rozo , Neal Dalal , James E. Taylor

We analyse the properties of substructures within dark matter halos (subhalos) using a set of high-resolution numerical simulations of the formation of structure in a Lambda-CDM Universe. Our simulation set includes 11 high-resolution…

Astrophysics · Physics 2009-09-25 G. De Lucia , G. Kauffmann , V. Springel , S. D. M. White , B. Lanzoni , F. Stoehr , G. Tormen , N. Yoshida

The incidence of sub-galactic level substructures is an important quantity, as it is a generic prediction of high-resolution Cold Dark Matter (CDM) models which is susceptible to observational test. Confrontation of theory with observations…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 N. Jackson , S. E. Bryan , S. Mao , C. Li

We demonstrate that the flux ratios of 4-image lensed quasars provide a powerful means of probing the small scale structure of Dark Matter (DM) halos. A family of smooth lens models can precisely predict certain combinations of flux ratios…

Astrophysics · Physics 2009-11-07 R. Benton Metcalf , HongSheng Zhao

A fundamental prediction of the cold dark matter cosmology is the existence of a large number of dark subhalos around galaxies, most of which should be entirely devoid of stars. Confirming the existence of dark substructures stands among…

Astrophysics of Galaxies · Physics 2018-08-01 Andrew S. Graus , James S. Bullock , Michael Boylan-Kolchin , Anna M. Nierenberg

Constraining the distribution of small-scale structure in our universe allows us to probe alternatives to the cold dark matter paradigm. Strong gravitational lensing offers a unique window into small dark matter halos ($<10^{10} M_\odot$)…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-08 Sebastian Wagner-Carena , Jelle Aalbers , Simon Birrer , Ethan O. Nadler , Elise Darragh-Ford , Philip J. Marshall , Risa H. Wechsler

High-resolution N-body simulations of dark matter halos indicate that the Milky Way contains numerous subhalos. When a dark matter subhalo passes in front of a star, the light from that star will be deflected by gravitational lensing,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Adrienne L. Erickcek , Nicholas M. Law

We explore the use of strong lensing by galaxy clusters to constrain the dark energy equation of state and its possible time variation. The cores of massive clusters often contain several multiply imaged systems of background galaxies at…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Anson D'Aloisio , Priyamvada Natarajan

Cosmological simulations predict that galaxies are embedded into triaxial dark matter haloes, which appear approximately elliptical in projection. Weak gravitational lensing allows us to constrain these halo shapes and thereby test the…

The distortion of the images of faint high-redshift galaxies can be used to probe the intervening mass distribution. This weak gravitational lensing effect has been used recently to study the (projected) mass distribution of several…

Astrophysics · Physics 2009-10-30 Guido Kruse , Peter Schneider