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Related papers: Dark matter caustics

200 papers

The velocity distribution of the dark matter particles on the outskirts of the Solar System remains unclear. We suggest to determine it using experimentally found properties of the oldest halo objects. Indeed, the oldest halo stars and…

High Energy Astrophysical Phenomena · Physics 2015-05-27 Anton N. Baushev

We measure the projected density profile, shape and alignment of the stellar and dark matter mass distribution in 11 strong-lens galaxies. We find that the projected dark matter density profile - under the assumption of a Chabrier stellar…

Based on dynamical constraints about the Hubble sequence evolution, observational data and a number of "conspiracies", we propose that the dark matter around spiral galaxies is in the form of cold gas, essentially in molecular form and…

Astrophysics · Physics 2011-05-23 D. Pfenniger , F. Combes , L. Martinet

We study the gravitational lensing properties of a massive object in a dark matter halo, concentrating on the critical curves and caustics of the combined lens. We model the system in the simplest approximation by a point mass embedded in a…

Astrophysics of Galaxies · Physics 2021-11-25 Michal Karamazov , Lukas Timko , David Heyrovsky

There is strong evidence for a large fraction of dark matter in the Universe. Some of the evidence and candidates for dark matter are reviewed. Dark matter in spiral galaxies may be in the form of cold dense clouds of molecular hydrogen.…

Astrophysics · Physics 2007-05-23 Achim Tappe

An argument is presented that the dark matter is axions, at least in part. It has three steps. First, axions behave differently from the other forms of cold dark matter because they form a rethermalizing Bose-Einstein condensate (BEC).…

Cosmology and Nongalactic Astrophysics · Physics 2012-10-02 P. Sikivie

Considering the flat rotation curves as input and treating the matter content in the galactic halo region as quark matter, we have found out a background spacetime metric for the region of the galactic halo. We obtain fairly general…

General Relativity and Quantum Cosmology · Physics 2012-07-19 Farook Rahaman , P. K. F. Kuhfittig , Ruhul Amin , Gurudas Mandal , Saibal Ray , Nasarul Islam

Deep observations of galaxy outskirts reveal faint extended stellar components (ESCs) of streams, shells, and halos, which are ghostly remnants of the tidal disruption of satellite galaxies. We use cosmological galaxy formation simulations…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-29 Chris Power

We present the first and so far the only simulations to follow the fine-grained phase-space structure of galaxy haloes formed from generic LCDM initial conditions. We integrate the geodesic deviation equation in tandem with the N-body…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Mark Vogelsberger , Simon D. M. White

Dark matter is the dominant form of matter in the universe, but its nature is unknown. It is plausibly an elementary particle, perhaps the lightest supersymmetric partner of known particle species. In this case, annihilation of dark matter…

Recent work on the mass distribution in spiral galaxies, using mainly HI observations, is reviewed. The principal problem is still to determine to what extent the dark matter is important in the inner parts of a galaxy, or in other words,…

Astrophysics · Physics 2007-05-23 A. Bosma

The spatial distributions of luminous and dark matter in massive early-type galaxies reflect the formation processes which shaped these systems. This article reviews the predictions of cosmological simulations for the dark and baryonic…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Ortwin Gerhard

We study how the internal structure of dark halos is affected if Cold Dark Matter particles are assumed to have a large cross-section for elastic collisions. We identify a cluster halo in a large cosmological N-body simulation and…

Astrophysics · Physics 2009-10-31 N. Yoshida , V. Springel , S. D. M. White , G. Tormen

We investigate in detail the mass distribution obtained by means of high resolution rotation curves of 25 galaxies of different morphological types. The dark matter contribution to the circular rotation velocity is well-described by…

Astrophysics · Physics 2011-02-11 F. Donato , G. Gentile , P. Salucci

Dark-matter halos are the scaffolding around which galaxies and clusters are built. They form when the gravitational instability of primordial density fluctuations causes regions which are denser than average to slow their cosmic expansion,…

Astrophysics · Physics 2007-05-23 Paul R. Shapiro , Ilian T. Iliev , Hugo Martel , Kyungjin Ahn , Marcelo A. Alvarez

In the standard theory of the large scale structure formation, matter accretes onto high density perturbations via gravitational instability. Collisionless dark matter forms caustics around such structures, while collisional baryonic matter…

Astrophysics · Physics 2007-05-23 Dongsu Ryu , Hyesung Kang

It is known that the gravitational collapse of cold dark matter leads to infinite-density caustics that seed the primordial dark-matter halos in the large-scale structure. The development of these caustics begins, generically, as an almost…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-25 Cornelius Rampf , Uriel Frisch , Oliver Hahn

We discuss what we call halo or galaxy root systems, collections of particle pathlines that show the infall of matter from the initial uniform distribution into a collapsed structure. The matter clumps as it falls in; projected through…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-22 Mark Neyrinck , Miguel Aragón-Calvo , István Szapudi

After deducing the density profiles and gravitational potential functions of eight galaxies from the rotation velocity data from THINGS, we find that the density decreases exponentially with the potential in substantial regions of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Joshua Davidson , Sanjoy K. Sarker , Allen Stern

We use N-body simulations to investigate the structure of dark halos in the standard Cold Dark Matter cosmogony. Halos are excised from simulations of cosmologically representative regions and are resimulated individually at high…

Astrophysics · Physics 2008-11-26 Julio F. Navarro , Carlos S. Frenk , Simon D. M. White