English
Related papers

Related papers: Anisotropic Models of Dark Halos

200 papers

The model of galactic halo as a system of the collisionless small neutral particles from the standpoint of kinetic theory is considered. For the equilibrium system with the use of Maxwell-Boltzmann distribution we obtained results which…

General Relativity and Quantum Cosmology · Physics 2011-11-03 Valentin D. Gladush

The anomalous rotation curves of galaxies provide compelling evidence for dark matter, yet its fundamental nature and distribution remain key unresolved issues in astrophysics. In this work, we investigate a dark matter model derived from…

General Relativity and Quantum Cosmology · Physics 2025-09-17 Jan Kuncewicz

A new model for the postcollapse equilibrium structure of virialized objects which condense out of the cosmological background universe is described and compared with observations and simulations of cosmological halos from dwarf galaxies to…

Astrophysics · Physics 2009-09-25 Paul R. Shapiro , Ilian T. Iliev

New exact interior solutions to the Einstein field equations for anisotropic spheres are found. We utilise a procedure that necessitates a choice for the energy density and the radial pressure. This class contains the constant density model…

General Relativity and Quantum Cosmology · Physics 2009-11-11 M. Chaisi , S. D. Maharaj

Many dynamical models of the Milky Way halo require assumptions that the distribution function of a tracer population should be independent of time (i.e., a steady state distribution function) and that the underlying potential is spherical.…

Astrophysics of Galaxies · Physics 2017-07-28 Wenting Wang , Jiaxin Han , Shaun Cole , Carlos Frenk , Till Sawala

Einstein field equations for anisotropic spheres are solved and exact interior solutions obtained. This paper extends earlier treatments to include anisotropic models which accommodate a wider variety of physically viable energy densities.…

General Relativity and Quantum Cosmology · Physics 2008-11-26 M. Chaisi , S. D. Maharaj

A method is presented for finding anisotropic distribution functions for stellar systems with known, spherically symmetric, densities, which depends only on the two classical integrals of the energy and the magnitude of the angular…

Astrophysics · Physics 2008-12-31 Zhenglu Jiang , Leonid Ossipkov

We propose a new numerical procedure to simulate a single dark halo of any size and mass in a hierarchical framework coupling the extended Press-Schechter formalism (EPSF) to N-body simulations. The procedure consists of assigning…

Astrophysics · Physics 2009-11-07 Elena D'Onghia , Claudio Firmani , Guido Chincarini

We present the class of regular homogeneous T-models with vacuum dark fluid, associated with a variable cosmological term. The vacuum fluid is defined by the symmetry of its stress-energy tensor, i.e., its invariance under Lorentz boosts in…

General Relativity and Quantum Cosmology · Physics 2008-11-26 K. A. Bronnikov , I. G. Dymnikova

We examine the proposal that a model of the large-scale matter distribution consisting of randomly placed haloes with power-law profile, as opposed to a fractal model, can account for the observed power-law galaxy-galaxy correlations. We…

Astrophysics · Physics 2008-11-26 Jose Gaite

We study the dynamical properties of spherical galaxies with surface luminosity profile described by the R^{1/m}-law, in which a variable degree of orbital anisotropy is allowed. The parameter m for the present models covers the range…

Astrophysics · Physics 2007-05-23 L. Ciotti , B. Lanzoni

Astronomical observations strongly suggest that our universe is now accelerating and contains a substantial admixture of dark vacuum energy. Using numerical simulations to study this newly consolidated cosmological model (with a constant…

Astrophysics · Physics 2009-11-10 Fred C. Adams , Michael T. Busha , August E. Evrard , Risa H. Wechsler

By starting with a seed Newtonian potential-density pair we construct relativistic thick spherical shell models for a Majumdar-Papapetrou type conformastatic spacetime. As a simple example, we consider a family of Plummer-Hernquist type…

General Relativity and Quantum Cosmology · Physics 2017-02-13 Gonzalo García-Reyes

We present a percent-level accurate model of the line-of-sight velocity distribution of galaxies around dark matter halos as a function of projected radius and halo mass. The model is developed and tested using synthetic galaxy catalogs…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-05 Han Aung , Daisuke Nagai , Eduardo Rozo , Brandon Wolfe , Susmita Adhikari

(Abridged) We describe a new iterative approach for the realization of equilibrium N-body systems for given density distributions. Our method uses elements of Schwarzschild's technique and of the made-to-measure method, but is based on a…

Cosmology and Nongalactic Astrophysics · Physics 2014-08-20 Denis Yurin , Volker Springel

We study the stability of rotating collisionless self-gravitating spherical systems by using high resolution N-body experiments on a Connection Machine CM-5. We added rotation to Ossipkov-Merritt (hereafter OM) anisotropic spherical systems…

Astrophysics · Physics 2009-10-31 J. -M. Alimi , J. Perez , A. Serna

We study the bar instability in collisionless, rotating, anisotropic, stellar systems, using N-body simulations and also the matrix technique for calculation of modes with the perturbed collisionless Boltzmann equation. These methods are…

Astrophysics of Galaxies · Physics 2021-02-17 Philip G. Breen , Simon Rozier , Douglas C. Heggie , Anna Lisa Varri

The shapes of individual self-gravitating structures of an ensemble of identical, collisionless particles have remained elusive for decades. In particular, a reason why mass density profiles like the Navarro-Frenk-White or the Einasto…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-01 Jenny Wagner

Nonlinear models for pattern evolution by ion beam sputtering on a material surface present an ongoing opportunity for new numerical simulations. A numerical analysis of the evolution of preexisting patterns is proposed to investigate…

Materials Science · Physics 2021-04-30 E. Vitral , D. Walgraef , J. Pontes , G. R. Anjos , N. Mangiavacchi

The gravitationally-driven evolution of cold dark matter dominates the formation of structure in the Universe over a wide range of length scales. While the longest scales can be treated by perturbation theory, a fully quantitative…

Astrophysics · Physics 2009-11-10 Katrin Heitmann , Paul M. Ricker , Michael S. Warren , Salman Habib