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Related papers: New Results on Bar-Halo Interactions

200 papers

We use fully self-consistent N-body simulations of barred galaxies to show that dynamical friction from a dense dark matter halo dramatically slows the rotation rate of bars. Our result supports previous theoretical predictions for a bar…

Astrophysics · Physics 2010-01-28 Victor P. Debattista , J. A. Sellwood

N-body simulations argue that the inner haloes of barred galaxies should not be spherical, nor even axisymmetric, but triaxial. The departure from sphericity is strongest near the centre and decreases outwards; typical axial ratios for the…

Astrophysics · Physics 2008-11-26 E. Athanassoula

A significant fraction of local galaxies exhibit stellar bars, non-axisymmetric structures composed of stars, gas, and dust. Identifying key differences between the properties of barred and unbarred galaxies can uncover clues about the…

Astrophysics of Galaxies · Physics 2025-05-23 Paula D. López , Cecilia Scannapieco , Sofía A. Cora , Ignacio D. Gargiulo

Using high resolution N-body simulations of stellar disks embedded in cosmologically motivated dark matter halos, we study the evolution of bars and the transfer of angular momentum between halos and bars. We find that dynamical friction…

Astrophysics · Physics 2009-11-07 Octavio Valenzuela , Anatoly Klypin

We present a general recipe for constructing N-body realizations of galaxies comprised of near-spherical and disc components. First, an exact spherical distribution function for the spheroids (halo & bulge) is determined, such that it is in…

Astrophysics · Physics 2008-11-26 Paul J. McMillan , Walter Dehnen

Angular momentum redistribution within barred galaxies drives their dynamical evolution. Angular momentum is emitted mainly by near-resonant material in the bar region and absorbed by resonant material mainly in the outer disc and in the…

Astrophysics · Physics 2009-11-10 E. Athanassoula

The emergence of a large-scale stellar bar is one of the most striking features in disc galaxies. By means of state-of-the-art cosmological zoom-in simulations, we study the formation and evolution of bars in Milky Way-like galaxies in a…

Astrophysics of Galaxies · Physics 2018-07-23 Tommaso Zana , Massimo Dotti , Pedro R. Capelo , Silvia Bonoli , Francesco Haardt , Lucio Mayer , Daniele Spinoso

Bars in galaxies may develop through a global instability or due to an interaction with another system. We study bar formation in disky dwarf galaxies orbiting a Milky Way-like galaxy. We employ $N$-body simulations to study the impact of…

Astrophysics of Galaxies · Physics 2017-06-28 Grzegorz Gajda , Ewa L. Lokas , E. Athanassoula

Aims: We want to investigate the growth of bar instability in stellar disks embedded in a suitable dark matter halo evolving in a fully consistent cosmological framework. Methods: We perform seven cosmological simulations to emphasise the…

Astrophysics · Physics 2009-11-11 Anna Curir , Paola Mazzei , Giuseppe Murante

For several decades it has been known that stellar bars in disc galaxies can be triggered by interactions, or by internal processes such as dynamical instabilities. In this work, we explore the differences between these two mechanisms using…

Stellar bars in disk galaxies grow as stars in near circular orbits lose angular momentum to their environments, including their Dark Matter (DM) halo, and transform into elongated bar orbits. This angular momentum exchange during galaxy…

Astrophysics of Galaxies · Physics 2024-10-04 Sioree Ansar , Mousumi Das

Using N-body simulations, we examine the impact of dark matter (DM) halo resolution and gravitational softening on bar formation. We generate isolated disk-halo systems with fixed stellar disk parameters, varying the number of halo…

Astrophysics of Galaxies · Physics 2026-03-04 S. Kwak , I. Minchev , M. Steinmetz , S. K. Yi

We study the formation of stellar bars using 145 simulations of disc galaxies embedded in live and static dark matter haloes. We use the exponential bar growth timescale, $\tau_{\rm bar}$, to quantify how disc structure and kinematics…

Astrophysics of Galaxies · Physics 2026-02-26 Matthew Frosst , Danail Obreschkow , Aaron Ludlow

We demonstrate that the chaotic nature of N-body systems can lead to macroscopic variations in the evolution of collisionless simulations containing rotationally supported discs. The unavoidable stochasticity that afflicts all simulations…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 J. A. Sellwood , Victor P. Debattista

While bars are commonly observed in disk galaxies, the precise conditions governing their formation remain incompletely understood. To investigate these conditions, we perform a suite of N-body simulations of bulgeless disk galaxies with…

Astrophysics of Galaxies · Physics 2025-09-10 Dajeong Jang , Woong-Tae Kim , Yun Hee Lee

The predicted central densities of dark matter halos in LCDM models exceed those observed in some galaxies. Weinberg & Katz argue that angular momentum transfer from a rotating bar in the baryonic disk can lower the halo density, but they…

Astrophysics · Physics 2009-11-11 J. A. Sellwood

Disc galaxies can be substantially modified by close encounters and mergers, since their discs are very responsive components. Close interactions can be held responsible for the formation of bridges and tails, as well as for the formation…

Astrophysics · Physics 2007-05-23 E. Athanassoula

We present a new method for embedding a stellar disc in a cosmological dark matter halo and provide a worked example from a {\Lambda}CDM zoom-in simulation. The disc is inserted into the halo at a redshift z = 3 as a zero-mass rigid body.…

Astrophysics of Galaxies · Physics 2018-01-31 Jacob S. Bauer , Lawrence M. Widrow , Denis Erkal

We investigate the evolution of angular momentum in simulations of galaxy formation in a cold dark matter universe. We analyse two model galaxies generated in the N-body/hydrodynamic simulations of Okamoto et al. Starting from identical…

Astrophysics · Physics 2010-12-08 J. Zavala , T. Okamoto , Carlos S. Frenk

Recent developments in computer hardware and software enable researchers to simulate the self-gravitating evolution of galaxies at a resolution comparable to the actual number of stars. Here we present the results of a series of such…

Astrophysics of Galaxies · Physics 2018-04-04 Michiko S. Fujii , Jeroen Bédorf , Junichi Baba , Simon Portegies Zwart